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  • Articles: DFG German National Licenses  (811)
  • Electronic Resource  (811)
  • 1985-1989  (811)
  • 1920-1924
  • 1890-1899
  • 1986  (811)
  • Inorganic Chemistry  (668)
  • pharmacokinetics  (143)
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  • Articles: DFG German National Licenses  (811)
Material
  • Electronic Resource  (811)
Years
  • 1985-1989  (811)
  • 1920-1924
  • 1890-1899
Year
Keywords
  • 101
    Electronic Resource
    Electronic Resource
    The intra- and inter-subject variability of Nifedipine pharmacokinetics in young volunteers (1986)
    Springer
    European journal of clinical pharmacology 30 (1986), S. 57-60 
    Details
    ISSN: 1432-1041
    Keywords: nifedipine ; pharmacokinetics ; oral contraceptives ; healthy volunteers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Plasma concentrations of Nifedipine were measured following single oral doses of Nifedipine Slow Release (Adalat Retard) on three separate occasions to young, healthy volunteers of both sexes. Intra- and inter-subject variability were assessed by comparing the pharmacokinetic parameters, AUC, Cmax and T50%AUC. Interindividual variability was less than that observed in other studies with the betablockers, metoprolol and propranolol and there was no evidence of differences between the sexes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00614196
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  • 102
    Electronic Resource
    Electronic Resource
    Pharmacokinetics and pharmacodynamics of the prostacyclin analogue iloprost in man (1986)
    Springer
    European journal of clinical pharmacology 30 (1986), S. 61-68 
    Details
    ISSN: 1432-1041
    Keywords: iloprost ; prostacyclin analogue ; pharmacokinetics ; platelet aggregation ; healthy male volunteers ; adverse effects
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Plasma levels of the prostacyclin analogue, iloprost, were measured by antibody/GC/MS in healthy male volunteers given 1 and 3 ng/kg per min i.v. for 45 min, and 1 µg/kg p.o. Following i.v. infusion, the steady-state plasma levels of iloprost were strictly dose-dependent (46±8 pg/ml and 135±24 pg/ml). The disposition was biphasic with half-lives of 3–4 min and 0.5 h. After oral administration, absorption of the drug was extremely rapid, the maximum plasma level of 251±32 pg/ml being achieved after 10±6 min. The bioavailability was 16±4%. Platelet aggregation induced by 2 µM ADP was reduced by 53% and 68% at the end of the two different infusions, and by 68% 15 min after p.o. administration. The ex-vivo inhibition of platelet aggregation by iloprost was not affected by preceding drug treatment. The cAMP content of platelets was increased by a factor of 2.5 at the end of the infusions and to a lesser extent 15 min after oral dosing. A slight increase in heart rate occurred during the infusion and within 30 min after oral administration; blood pressure was virtually unaffected. Except for transient side-effects (facial flush and headache) no adverse reactions were observed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00614197
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  • 103
    Electronic Resource
    Electronic Resource
    Pharmacokinetics of methysergide and its metabolite methylergometrine in man (1986)
    Springer
    European journal of clinical pharmacology 30 (1986), S. 75-77 
    Details
    ISSN: 1432-1041
    Keywords: methysergide ; methylergometrine ; first-pass metabolism ; pharmacokinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Five healthy men were given 1.0 mg methysergide maleate intravenously and 2.7 mg methysergide maleate orally in a cross-over study. The systemic availability of methysergide was only 13%, most probably due to a high degree of first-pass metabolism to methylergometrine. We also found evidence of extrahepatic clearance of methysergide. After oral administration the plasma concentrations of the metabolite were considerably higher than those of the parent drug and the area under the plasma concentration curve (AUC) for methylergometrine was more than ten times greater than for methysergide. Our findings may be relevant to the treatment of migraine if methylergometrine contributes to the effect of methysergide. Methylergometrine had a significantly longer elimination half-life than methysergide (223±43 min vs 62.0±8.3 min and 174±35 min vs 44.8±8.1 min in the oral and intravenous studies respectively).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00614199
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  • 104
    Electronic Resource
    Electronic Resource
    Effect of cirrhosis and renal failure on the kinetics of clotiazepam (1986)
    Springer
    European journal of clinical pharmacology 30 (1986), S. 89-92 
    Details
    ISSN: 1432-1041
    Keywords: clotiazepam ; liver cirrhosis ; renal insufficiency ; pharmacokinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The kinetics of a single 5-mg oral dose of the thienodiazepine clotiazepam was evaluated in a series of patients with biopsy-proven cirrhosis, and in patients with renal insufficiency requiring maintenance hemodialysis, compared to healthy matched controls. Clotiazepam volume of distribution (Vz) was significantly smaller in cirrhotic patients than in controls (1.83 vs 2.57 l/kg), and total clearance was likewise reduced (2.15 vs 3.15 ml/min/kg). Elimination half-life was similar between groups (10.0 vs. 10.2h). There were no significant differences between renal failure and control patients in clotiazepam Vz, oral clearance, or elimination half-life. Thus cirrhosis is associated with reduced clearance of clotiazepam, probably due to impairment of its microsomal oxidation. However clotiazepam disposition is not significantly altered in dialysis-dependent renal insufficiency patients.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00614202
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  • 105
    Electronic Resource
    Electronic Resource
    The effects of age and chronic liver disease on the elimination of temazepam (1986)
    Springer
    European journal of clinical pharmacology 30 (1986), S. 93-97 
    Details
    ISSN: 1432-1041
    Keywords: temazepam ; liver disease ; elimination ; pharmacokinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The pharmacokinetics of the newer 1, 4 benzodiazepine temazepam were evaluated in 16 healthy subjects aged 18–92 years and in 15 cirrhotic patients, to ascertain the effect of ageing and liver disease. The data were analysed both by classic two compartment and by non-compartmental methods. The mean elimination half-life in the control subjects was 15.5 h, considerably longer than previous estimates. No correlation was found between age and pharmacokinetic parameters. The cirrhotic group showed no statistically significant difference in the pharmacokinetic parameters nor in the urinary recovery of the dose from the control group. Temazepam plasma protein binding was assessed in a second group of 9 cirrhotics of similar severity to the main group and in matched controls. When these binding data were applied to the mean clearance data, a modest although not statistically significant, reduction in free drug clearance was observed in the cirrhotic group. This study adds further support to the observation that drugs which undergo ether glucuronidation have normal elimination patterns in patients with liver disease. Temazepam may prove to be a useful hypnotic sedative in patients with liver disease.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00614203
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  • 106
    Electronic Resource
    Electronic Resource
    Cirrhosis of the liver markedly impairs the elimination of mexiletine (1986)
    Springer
    European journal of clinical pharmacology 30 (1986), S. 83-88 
    Details
    ISSN: 1432-1041
    Keywords: mexiletine ; cirrhosis of the liver ; antiarrhythmic agents ; pharmacokinetics ; intravenous administration ; protein binding
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary To study the effects of cirrhosis of the liver on the pharmacokinetics of mexiletine a single i.v. dose of 200 mg was administered to six cirrhotic patients and to six healthy controls. The distribution of mexiletine in both study groups was similar, as indicated by similar values of V1 and Vss, but it tended to occur more slowly in the cirrhotics. The plasma protein binding of mexiletine was unchanged in the patients with cirrhosis. The elimination of mexiletine was markedly retarded in the cirrhotics, as indicated by its lower total clearance (2.31 vs. 8.27 ml/kg/h,) lower total elimination rate constant (0.059 vs 0.353 h−1), and longer elimination half-life (28.7 vs 9.9 h). The antipyrine half-life was 38.3 h in the patients and 14.7 h in the controls. One healthy volunteer had a Morgagni-Stokes-Adams type of syncopal attack 5 min after administration of mexiletine due to disturbance of AV conduction induced by the drug. Thus, on a pharmacokinetic basis the loading dose of mexiletine need not be modified in cirrhotic patients, whereas the maintenance dosage should be reduced to one fourth — one third of the usual dose.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00614201
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  • 107
    Electronic Resource
    Electronic Resource
    Ceftriaxone pharmacokinetics following multiple intramuscular dosing (1986)
    Springer
    European journal of clinical pharmacology 30 (1986), S. 109-112 
    Details
    ISSN: 1432-1041
    Keywords: ceftriaxone ; intramuscular ; pharmacokinetics ; steady-state
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The steady-state pharmacokinetics and tolerance of ceftriaxone after multiple i.m. doses of 0.5 and 1 g q12 h for 3.5 days were investigated in 12 healthy, adult volunteers. Ceftriaxone was rapidly absorbed after i.m. administration with mean peak times ranging from 1.3 to 1.9 h. Steady-state plasma concentrations were apparent after the third dose of both dosage regimens, with trough plasma concentrations of 24±6 and 39±8 µg/ml (mean±SD) after the 0.5 and 1 g q12 h regimens, respectively. Multiple i.m. administrations of ceftriaxone did not alter its elimination half-life; however, small increases were observed in the plasma clearance and volume of distribution at the 1-g regimen. These increases were attributed to the non-linear binding of ceftriaxone to human plasma proteins, and are therapeutically unimportant. Ceftriaxone was well tolerated and serious or lasting adverse reactions were not encountered in the study.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00614206
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  • 108
    Electronic Resource
    Electronic Resource
    Pharmacokinetics of dezocine, a new analgesic: Effect of dose and route of administration (1986)
    Springer
    European journal of clinical pharmacology 30 (1986), S. 121-123 
    Details
    ISSN: 1432-1041
    Keywords: dezocine ; opioid analgesics ; pharmacokinetics ; healthy volunteers ; bioavailability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The pharmacokinetics of intravenous (IV) dezocine, and bioavailability of intramuscular (IM) and subcutaneous (SQ) dezocine, were evaluated in healthy male volunteers. Elimination half-life following 5, 10, and 20 mg IV doses averaged 2.6–2.8 h, and was independent of dose. Clearance decreased slightly, although significantly, with dose. After Deltoid IM injection, dezocine was rapidly absorbed (peak level: 0.6 h after dose), with bioavailability 97%. Thus dezocine has extensive distribution, high clearance and short half-life over a range of IV doses. It is rapidly and completely absorbed following IM or SQ administration.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00614208
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  • 109
    Electronic Resource
    Electronic Resource
    Comparison of single and multiple dose pharmacokinetics of theophylline using stable isotopes (1986)
    Springer
    European journal of clinical pharmacology 30 (1986), S. 113-120 
    Details
    ISSN: 1432-1041
    Keywords: theophylline ; pharmacokinetics ; stable isotopes ; diurnal variation ; single dose administration ; multiple dose administration ; systemic availability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Theophylline, enriched with the stable isotopes13C and15N, was administered intravenously in a dose of 10 mg to 8 healthy men following single (200 mg) and multiple (200 mg 8-hourly for 5 days) oral dose administration of aminophylline. Total plasma clearance, volume of distribution, and half-time determined from the intravenous data were similar, demonstrating that the pharmacokinetics of theophylline after chronic dosing can be predicted from the pharmacokinetics of a single dose. With chronic oral dosing, however, the mean trough concentration was 12% higher at 9 a.m. than at 5 p.m., the end of the dose interval (3.94±0.55 vs. 3.50±0.45 µg·ml−1). The AUC following oral dosing was 25% higher in the multiple dose study than in the single dose study. Simulation analysis suggested that these results could be explained by diurnal variation in the clearance or absorption rate or a combination of both. Thus, the systemic availability of theophylline measured during a single dosage interval after chronic oral dosing to steady state would be overestimated in comparison with that measured after a single oral dose.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00614207
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  • 110
    Electronic Resource
    Electronic Resource
    Single dose oxazepam has no effect on acetaminophen clearance or metabolism (1986)
    Springer
    European journal of clinical pharmacology 30 (1986), S. 127-129 
    Details
    ISSN: 1432-1041
    Keywords: oxazepam ; acetaminophen clearance ; metabolite formation ; glucuronidation ; pharmacokinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The metabolism of acetaminophen and oxazepam in humans is mainly dependent on the microsomal capacity for glucuronide conjugation. The clearance of acetaminophen and the formation of metabolites were evaluated in 7 patients before and during concomitant administration of oxazepam 30 mg. The subjects received a single 500 mg dose of acetaminophen i.v. and concentrations in plasma were measured for 360 minutes and in urine for 24 h in order to estimate the production of metabolites. The single therapeutic dose of oxazepam had no effect on the clearance of acetaminophen or on formation of its metabolites.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00614210
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  • 111
    Electronic Resource
    Electronic Resource
    Treatment of essential hypertension with felodipine in combination with a diuretic (1986)
    Springer
    European journal of clinical pharmacology 30 (1986), S. 133-139 
    Details
    ISSN: 1432-1041
    Keywords: felodipine ; hydrochlorothiazide ; essential hypertension ; calcium antagonist ; pharmacokinetics ; plasma noradrenaline ; adverse effects
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary In a double-blind cross-over study, the effect on blood pressure (BP), heart rate (HR) and plasma noradrenaline concentration (pNA) of placebo or felodipine given in addition to hydrochlorothiazide was studied in 12 male patients with essential hypertension, not satisfactorily controlled with the diuretic alone. The first dose of felodipine decreased BP and increased HR for about 6 h. After 4 weeks of treatment with felodipine, BP was reduced for 24 h, whereas HR was only transiently increased. The elimination half-life of felodipine was about 23 h. The plasma noradrenaline concentration increased after felodipine and serum uric acid decreased. Side-effects were few and usually mild.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00614290
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  • 112
    Electronic Resource
    Electronic Resource
    Pharmacokinetics and pharmacodynamics in man of the dopamine antagonist ergot derivative, bromerguride (1986)
    Springer
    European journal of clinical pharmacology 31 (1986), S. 165-168 
    Details
    ISSN: 1432-1041
    Keywords: bromerguride ; dopamine antagonist ; pharmacokinetics ; pharmacodynamics ; prolactin level ; side-effects ; healthy volunteers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The plasma levels and urinary excretion of the dopamine antagonist, bromerguride, were measured by radioimmunoassay in healthy male volunteers given 50 µg i.v. and oral doses of 1 and 2 mg. Plasma prolactin was also measured by radioimmunoassay. Following i.v. injection, the concentration of bromerguride declined biphasically, with half-lives of 7 min and 1.2h. The total clearance was 32 ml·min−1·kg−1 and the apparent volume of distribution was 3.6 l/kg. The bioavailability of oral bromerguride was 29% after 1 mg and 25% after 2 mg. The drug was almost totally metabolized and less than 0.05% of the dose was excreted in urine in 24 h after oral administration. Plasma prolactin levels were increased in a dose-dependent manner for about 8 h. Side-effects were minimal, mainly being tiredness and headache in some of the volunteers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00606653
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  • 113
    Electronic Resource
    Electronic Resource
    Pharmacokinetics of tenoxicam in patients with impaired renal function (1986)
    Springer
    European journal of clinical pharmacology 29 (1986), S. 697-701 
    Details
    ISSN: 1432-1041
    Keywords: tenoxicam ; renal insufficiency ; non-steroidal antiinflammatory agents ; protein binding ; metabolism ; pharmacokinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The pharmacokinetics of tenoxicam after a single oral dose of 20 mg has been studied in 12 patients with various degrees of decreased renal function. Unchanged tenoxicam and its 5′OH-metabolite in plasma and urine were determined by HPLC. The mean areas under the plasma concentration-time curve (138±53 µg/ml·h) and terminal half-lives in patients with impaired renal function did not differ from values previously reported in normal volunteers, nor did the peak concentration of tenoxicam. The half-life of 5′OH-tenoxicam and unchanged tenoxicam where the same. The urinary excretion of 5′OH-tenoxicam fell with decreasing renal function. Thus no dosage adjustment should be necessary and the usual daily dose of tenoxicam may be administered once daily also to patients with renal failure.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00615961
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  • 114
    Electronic Resource
    Electronic Resource
    The pharmacokinetics after intravenous and oral administration in man of theα 2-adrenoreceptor antagonist idazoxan (RX781094) (1986)
    Springer
    European journal of clinical pharmacology 29 (1986), S. 743-745 
    Details
    ISSN: 1432-1041
    Keywords: idazoxan ; pharmacokinetics ; alpha 2-adrenoceptor antagonist ; healthy volunteers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary A high performance liquid chromatographic method was developed for the quantitative determination of idazoxan in plasma. The assay was used to study the disposition of the drug after intravenous infusion and oral administration to five normal subjects. After i.v. administration the kinetics could be described by a two compartment model with a mean elimination half life of 4.20 h. The mean calculated volume of distribution during the elimination phase was 3.20 l/kg−1 and the mean plasma clearance was 824 ml min−1. After oral administration a lag period before onset of absorption was observed in all five volunteers, the plasma levels declining monoexponentially from the peak concentration with a mean elimination half life of 5.58 h. The absolute availability varied between 26% and 41% with a mean value of 34%. Invitro measurements produced a blood/plasma ratio of 1.3 for idazoxan.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00615972
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  • 115
    Electronic Resource
    Electronic Resource
    Pharmacokinetics of temazepam in geriatric patients (1986)
    Springer
    European journal of clinical pharmacology 30 (1986), S. 745-747 
    Details
    ISSN: 1432-1041
    Keywords: temazepam ; pharmacokinetics ; geriatric patients ; benzodiazepines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary A single dose of temazepam 10 mg, as a solution in soft gelatin capsules, was given to 10 fasting geriatric in-patients (mean age 83 years) in a stable clinical condition. The mean peak plasma concentration was 306 ng/ml, with a median time of 0.75 h to peak concentration. Temazepam was eliminated from plasma in a biexponential manner, with a distribution phase (mean t1/2α=0.7 h) predominating for 3 h. The drug had a mean elimination half-life of 8.7 h. In a chronic study, in which temazepam 10 mg p.o. was given nightly to 13 patients, the plasma concentrations on Days 3, 5, 8, 12 and 15 were not significantly different from each other, showing rapid attainment of steady state levels and the lack of drug accumulation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00608229
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  • 116
    Electronic Resource
    Electronic Resource
    5-Aminosalicylic acid in patients with an ileo-rectal anastomosis (1986)
    Springer
    European journal of clinical pharmacology 31 (1986), S. 23-26 
    Details
    ISSN: 1432-1041
    Keywords: sulphasalazine ; Pentasa ; slow release preparation ; 5-aminosalicylic acid ; ileo-rectal anastomosis ; ulcerative colitis ; pharmacokinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The pharmacokinetics of 5-aminosalicylic acid (5-ASA) from sulphasalazine (SASP) and the slow-release 5-ASA preparation Pentasa was investigated in a cross-over study in 9 otherwise healthy patients with an ileo-rectal anastomosis. The 24-hour recoveries of the drugs were 90.5% and 84.7%, respectively. The median release of 5-ASA from SASP was 50% and from Pentasa 75%. Equal amounts of 5-ASA (18.0% vs 17.9%) were found in the faeces, and a significantly larger amount (4.4% vs 28.9%) of the metaboliteN-acetyl-5-aminosalicylic acid (ac-5-ASA) was found in faeces following Pentasa. A larger amount of 5-ASA was absorbed and subsequently excreted in the urine, mainly as the metabolite (2.5% vs 20.5%) from Pentasa. This confirms previous results in ileostomized patients treated with Pentasa. The present findings also demonstrate that bacterial azo-reduction of SASP in patients with ileorectal anastomosis may be an adequate way to deliver 5-ASA in this type of patient. Both treatments may be used in these patients during a flare up of ulcerative colitis, but randomized studies are needed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00870980
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  • 117
    Electronic Resource
    Electronic Resource
    Pharmacokinetics and metabolism of quinidine in extensive and poor metabolisers of sparteine (1986)
    Springer
    European journal of clinical pharmacology 31 (1986), S. 69-72 
    Details
    ISSN: 1432-1041
    Keywords: quinidine ; sparteine ; pharmacokinetics ; drug oxidation ; polymorphism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The pharmacokinetics and metabolism of quinidine were investigated in extensive and poor metabolisers of sparteine. No differences in plasma clearance, terminal half life, volume of distribution or cumulative urinary excretion of quinidine, 3-hydroxyquinidine and quinidine-N-oxide were observed between phenotypes. Thus, it is unlikely that quinidine metabolism is controlled by the sparteine/debrisoquine gene locus.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00870989
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  • 118
    Electronic Resource
    Electronic Resource
    Pharmacokinetics of intravenous and intraperitoneal ceftriaxone in chronic ambulatory peritoneal dialysis (1986)
    Springer
    European journal of clinical pharmacology 31 (1986), S. 479-483 
    Details
    ISSN: 1432-1041
    Keywords: ceftriaxone ; dialysis ; continous ambulatory peritoneal dialysis ; pharmacokinetics ; intraperitoneal administration ; intravenous administration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The kinetics of ceftriaxone was investigated in 8 patients without infection, who were receiving continuous ambulatory peritoneal dialysis (CAPD). Ceftriaxone 1 g was injected i.v. and 1 g was given intraperitoneally in the CAPD fluid during a 4-h dwell time. Ceftriaxone was assayed by HPLC. After intravenous administration, the kinetic parameters of ceftriaxone were: plasma t1/2, 12.3 h, total plasma clearance, 14.0 ml/min, volume of distribution at steady state 0.18 l/kg, and peritoneal clearance 0.59 ml/min. Over 72 hours only 5.5% of the dose was eliminated by the peritoneal route. After intraperitoneal administration, ceftriaxone rapidly appeared in serum; the absorption t1/2 was 1.1 h and the mean peak concentration was 38.8 µg/ml. The absorption of ceftriaxone from the peritoneal space was 39%. A single 1.0 g IP dose led to serum and dialysate concentrations of ceftriaxone above the minimum inhibitory concentration for susceptible pathogens for 24 hours.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00613528
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  • 119
    Electronic Resource
    Electronic Resource
    Diuretic activity, safety and pharmacokinetics of torasemide during chronic treatment in normal subjects (1986)
    Springer
    European journal of clinical pharmacology 31 (1986), S. 1-7 
    Details
    ISSN: 1432-1041
    Keywords: torasemide ; diuretic activity ; pharmacokinetics ; healthy subjects ; side-effects
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Torasemide 40 mg/day p.o. was administered for 21 days to 8 healthy volunteers to investigate its pharmacodynamics, pharmacokinetics and safety on chronic administration. It induced a highly significant initial increase in 24-h urinary volume and 24-h excretion of sodium and chloride, but its affect diminished after the first days. On Days 0, 1, 10 and 21 the experiement was divided in 3 clearance phases, extending from 0 to 2 h, 2 to 6 h and 6 to 24 h after dosing. The fractional excretion of sodium, chloride, potassium, calcium, magnesium and inorganic phosphates peaked during the first 2 h and returned almost to the control value during the following two clearance phases. The phase-dependent changes were significant for all electrolytes, except for potassium and inorganic phosphate. Plasma electrolyte levels remained constant throughout the study, except for a small decrease in chloride and potassium and for an increase in calcium and magnesium. Fasting blood glucose and glucose tolerance test were unaffected. A small but significant decrease in LDL-cholesterol was observed on Day 10. Other plasma lipid components showed minor changes. Plasma uric acid levels were moderately increased. There was no significant change of the creatinine clearance. Body weight fell significantly (by about 2 kg) during the study. Tonal audiometry was normal before and after the study. There was no significant difference between the plasma levels of torasemide on Days 1, 10 and 21, nor between its elimination half-life on Days 1 and 21. Side-effects consisted mainly of fatigue and low-back pain on days of intense diuresis. There were no toxic symptoms. ECG recordings and blood pressure remained within normal limits.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00541460
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  • 120
    Electronic Resource
    Electronic Resource
    Comparative analysis of the pharmacokinetics of unsubstituted N1-derivatives of 1,4-benzodiazepine (1986)
    Springer
    Bulletin of experimental biology and medicine 101 (1986), S. 206-209 
    Details
    ISSN: 1573-8221
    Keywords: 1,4-benzodiazepines ; pharmacokinetics ; plasma/brain concentration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00836121
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  • 121
    Electronic Resource
    Electronic Resource
    Pharmacokinetics of a water-soluble antioxidant of 3-hydroxypyridine type (1986)
    Springer
    Bulletin of experimental biology and medicine 101 (1986), S. 333-335 
    Details
    ISSN: 1573-8221
    Keywords: antioxidant ; 3-hydroxypyridines ; pharmacokinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00835938
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    Radioimmune and radioreceptor study of the pharmacokinetics of the enkephalin analog dalargin in man (1986)
    Springer
    Bulletin of experimental biology and medicine 101 (1986), S. 783-785 
    Details
    ISSN: 1573-8221
    Keywords: dalargin ; pharmacokinetics ; enkephalins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00839605
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  • 123
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    A dispersion model of hepatic elimination: 2. Steady-state considerations-influence of hepatic blood flow, binding within blood, and hepatocellular enzyme activity (1986)
    Springer
    Journal of pharmacokinetics and pharmacodynamics 14 (1986), S. 261-288 
    Details
    ISSN: 1573-8744
    Keywords: hepatic elimination ; hepatic clearance ; availability ; intrinsic clearance ; pharmacokinetics ; dispersion model ; well-stirred model ; tube model ; distributed model ; blood flow ; binding within blood ; hepatocellular enzyme activity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The dispersion model of hepatic elimination is based on the distribution of residence times of blood elements within the liver. The model has two asymptotic solutions corresponding to the “wellstirred” model (complete mixing of blood elements) and the “parallel-tube” model (no variation in residence times of blood elements). The steady-state form of the dispersion model relevant to pharmacokinetic analysis is developed and explored with respect to changes in blood flow, in binding within blood, and in hepatocellular enzyme activity. Literature data are used to evaluate discrepancies among the predictions of the dispersion, well-stirred, and tube models. It is concluded that the dispersion model is consistent-with the data. The limitations of steady-state perfusion experiments to estimate the residence time distribution of blood elements within the liver are considered.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01106707
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  • 124
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    In vivo interaction of the enantiomers of disopyramide in human subjects (1986)
    Springer
    Journal of pharmacokinetics and pharmacodynamics 14 (1986), S. 335-356 
    Details
    ISSN: 1573-8744
    Keywords: disopyramide ; pharmacokinetics ; stereoisomers ; antiarrhythmic agents
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Disopyramide, an antiarrhythmic agent, is marketed as a racemic mixture of two enantiomers. The racemic drug has unusual pharmacokinetic properties because of its concentration-dependent binding to plasma proteins in the therapeutic plasma concentration range. This study examined, in healthy subjects, the individual pharmacokinetic properties of both total and unbound d-and ldisopyramide in plasma after intravenous administration of each enantiomer separately (1.5mg/kg).Also investigated is the pharmacokinetics of total d-and l-disopyramide in plasma after intravenous administration of a pseudoracemate. Both d-and l-disopyramide are found to exhibit concentration-dependent binding to plasma proteins, with d-disopyramide being more avidly bound at lower concentrations. The stereoselective, concentration-dependent binding to plasma proteins resulted in distinct pharmacokinetic properties when the enantiomers were given together as the pseudoracemate. d-Disopyramide had a lower plasma clearance and renal clearance, a longer half-life, and a smaller apparent volume of distribution than l-disopyramide. However, when the enantiomers were administered separately, there were no differences in the clearance, renal clearance, and volume of distribution between enantiomers calculated from either total or unbound drug concentrations. The results reveal an important pharmacokinetic interaction between the enantiomers of disopyramide when given as a racemic mixture, which may be dose-dependent and is not apparent upon administration of the enantiomers separately.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01059195
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  • 125
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    The impact of neglecting nonlinear plasma-protein binding on disopyramide bioavailability studies (1986)
    Springer
    Journal of pharmacokinetics and pharmacodynamics 14 (1986), S. 365-379 
    Details
    ISSN: 1573-8744
    Keywords: disopyramide ; bioavailability ; protein binding ; nonlinear ; sustained release ; pharmacokinetics ; ultrafiltration ; immunoassay
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Disopyramide has nonlinear protein binding and thus the relationship between the extent of its bioavailability and AUC,the area under the plasma concentration-time curve, is (1) nonlinear and (2) absorption rate-dependent. The unbound species follows linear pharmacokinetics. A solution of disopyramide, the innovator's product, and two generic formulations were found to be statistically indistinguishable in their bioavailability of disopyramide, whether comparison was based upon AUCor area under the plasma unbound concentration-time curve (AUCu).The AUCand AUCugave similar results because of truly similar bioavailability, coupled with sufficiently similar release rates, among the four preparations chosen for study. The concentration dependence of disopyramide protein binding and the time course of unbound plasma concentrations were fit by models which then allowed prediction of AUCunder various biopharmaceutical scenarios. Nonlinear binding of disopyramide to plasma proteins renders AUCan insensitive parameter for the discrimination of products with different extents of bioavailability; immediate release products allowing bioavailabilities of 75 or 125% relative to the solution can generate AUCs86 and 112%, respectively, of that from the solution. Nonlinear binding, furthermore, leads to a tendency for AUC tooverestimate the bioavailability of slower release products in single-dose studies; if AUCwere the index of bioavailability, products permitting the same bioavailability as the solution but releasing over 12 hr could appear to allow 114% relative bioavailability. Moreover, in some situations the bias arising from the insensitivity of AUCto product differences can be reinforced by the dependence of AUCon release rate; an apparent relative bioavailability of 80% can be achieved by a 12-hr release product allowing a true relative bioavailability of a mere 58%. While multiple-dose studies appear largely to avoid the tendency to overestimate low bioavailability in slow-release products, in these studies AUCappears to be even more insensitive in resolving discrepancies between products. Assay technology now available makes AUCua feasible and more reliable index of bioavailability than AUCwhen plasma protein binding of drugs is nonlinear.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01059197
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  • 126
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    On the pharmacokinetics of 16-acetyl-gitoxin and its bioavailability from pengitoxin-containing tablet formulations (1986)
    Springer
    Journal of pharmacokinetics and pharmacodynamics 14 (1986), S. 357-364 
    Details
    ISSN: 1573-8744
    Keywords: 16-acetyi-gitoxin ; pengitoxin ; pharmacokinetics ; bioavailability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract In six volunteers the pharmacokinetics of 16-acetyI-gitoxin (16AG, 0.5mg) administered intravenously (A1) and as an oral solution (A2) and of pengitoxin (PAG, 0.6 mg) administered intravenously (A3) was evaluated. In six volunteers the bioavailability of 16AG from two PAG tablet formulations (1.2 mg) (B2, B3) was measured by comparison with the absorption after administration of a pengitoxin solution (1.2mg) (B1). In both studies the test was performed using a crossover design. After a single i.v. injection of equimolar doses, 16AG and PAG showed similar mean kinetic parameters: t 1/2 =51.6hr (16AG) and 60.8 hr (PAG), CL=11.7ml min−1 (16AG) and 12.7ml min−1 (PAG), CLR=4.1 ml min−1 (16AG) and 4.2ml min−1 (PAG). The 16AG was absorbed from solution with a mean half-life of 0.2hr to an extent of 98.6%. The mean urinary excretion /Ae(0, 4)/ of 16AG amounted to 24.6% (A1), 20.8% (A2) and 28.1% (A3). On the basis of AUCvalues, the mean bioavailability of PAG from either tablet formulation amounted to 79.6% (B2) and 89.6% (B3). The pharmacokinetic parameters of 16AG (PAG) are closer to those of digitoxin than those of digoxin. In general, 16AG is characterized as a digitoxin with a digoxin-like elimination half-life.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01059196
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    Pharmacokinetics of isosorbide dinitrate and its mononitrate metabolites after intravenous infusion (1986)
    Springer
    Journal of pharmacokinetics and pharmacodynamics 14 (1986), S. 1-17 
    Details
    ISSN: 1573-8744
    Keywords: isosorbide dinitratekw]isosorbide 2-mononitrate ; isosorbide 5-mononitrate ; metabolism ; pharmacokinetics ; modeling ; simultaneous estimation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Plasma concentrations of isosorbide dinitrate (ISDN) and its two active metabolites 2-isosorbide mononitrate (2-ISMN) and 5-isosorbide mononitrate (5-ISMN) have been measured during and for 6 hr after intravenous infusion at a rate of 2.5mg/hr during 1.75 hr in six cardiac patients, by a capillary gas chromatographic method. Data were analyzed by simultaneous modeling of the observed kinetics of the three compounds. Two or three phases were detected on the postinfusion ISDN concentration-time curves. ISDN concentrations declined with a mean terminal half-life of 2.81 hr±0.7 SD. The mean systemic clearance of ISDN (2.9 L/min ±0.7 SD) and its mean total volume of distribution (259 L +- 48 SD) were relatively high. Plasma 5-ISMN concentrations were 5- to 6-fold greater than those of 2-ISMN during the whole observation period. Maximum levels of 2-ISMN (6.7 ng/ml ± 0.9 SD) and of 5-ISMN (27 ng/ml ± 6 SD) occurred within a few minutes after the end of infusion. The mean half-lives of 2-ISMN (1.59 hr± 0.19 SD) and of 5-ISMN (3.78 hr± 0.79 SD) estimated by the model were smaller than those calculated by a model-independent method (2.95 hr± 0.41 SD and 5.98 hr± 2.22, respectively), but were in good agreement with those reported in the literature following separate administration of both metabolites to man. This study shows how such modeling can distinguish between metabolite formation and elimination processes and allow the determination of metabolite half-lives after administration of the precursor drug.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01059280
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    Physiological pharmacokinetic modeling ofcis-dichlorodiammineplatinum(II) (DDP) in several species (1986)
    Springer
    Journal of pharmacokinetics and pharmacodynamics 14 (1986), S. 131-155 
    Details
    ISSN: 1573-8744
    Keywords: pharmacokinetics ; physiological model ; cisplatin ; DDP ; cis-dichlorodiammineplatinum(II)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract A physiological pharmacokinetic analysis ofcis-dichlorodiammineplatinum(II) (DDP) is presented for the rabbit, dog, and human. The results are compared to a previous analysis for the rat. DDP binds irreversibly to low-molecular weight nucleophiles and macromolecules to form mobile and fixed metabolites at rates which are tissue-specific. The rate constant for the formation of fixed metabolite in plasma, determined by in vitro incubation, ranges from 0.004 to 0.008 min−1.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01065258
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    Receptor-mediated model relating anticonvulsant effect to brain levels of camazepam in the presence of its active metabolites (1986)
    Springer
    Journal of pharmacokinetics and pharmacodynamics 14 (1986), S. 309-321 
    Details
    ISSN: 1573-8744
    Keywords: camazepam ; temazepam ; oxazepam ; pharmacokinetics ; anticonvulsant effect ; radioreceptor assay ; rat ; mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract In a displacement test using3H-diazepam as a radioligand, the in vitro affinities of metabolites of camazepam (CZ) for the benzodiazepine receptors were 1–50 times more potent than that of CZ. In contrast, only three metabolites (temazepam, oxazepam, and hydroxy CZ), as well as CZ itself, exhibited an in vivo affinity parallel to their ability to protect against pentylenetetrazole-induced clonic convulsion in rats. In addition, CZ and these active metabolites displaced the radioligand from their receptor sites in a concentration-dependent saturable manner, indicating the competitive bimolecular interaction of these molecules with their receptors. The percent anticonvulsant effect was a nonlinear, single-valued function of the in vivo percent displacement of specific3H-diazepam binding, independent of these displacers after i.v. dosing; this relationship could be approximated by the Hill equation. On the basis of these findings, a receptor-mediated model, including the Langmuir equation to describe the receptor binding-brain concentration relationship and the Hill equation to accommodate the anticonvulsant effect-receptor binding relationship, was constructed. This model was found to adequately relate the time course values of anticonvulsant effect and of brain levels of CZ and its active metabolites after oral administration. These results demonstrate that CZ and its active metabolites exert anticonvulsant effect by competitive binding to the benzodiazepine receptors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01106709
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    Effect of caffeine on ceftriaxone disposition and plasma protein binding in the rat (1986)
    Springer
    Journal of pharmacokinetics and pharmacodynamics 14 (1986), S. 397-408 
    Details
    ISSN: 1573-8744
    Keywords: caffeine ; ceftriaxone ; plasma ; tissue ; pharmacokinetics ; compartment model ; protein binding
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Previous studies have shown that caffeine can affect drug kinetics by altering drug binding to plasma protein, drug absorption, or drug distribution. In this study, the effect of caffeine on the in vivoprotein binding and the disposition of ceftriaxone (a highly protein-bound cephalosporin) were investigated in the rat. Ceftriaxone 100mg/kg and caffeine 20mg/kg were i.v. injected via the tail vein and ceftriaxone in plasma, plasma filtrate, urine, feces, and tissues (brain, heart, kidney, liver, gut, lung, and muscle) was assayed by HPLC with UV detection. The fraction of free ceftriaxone in plasma ranged from 5.6 to 32.8% of total ceftriaxone (3–347 μg/ml) without caffeine and showed no alteration by caffeine. The total amount of ceftriaxone excreted in urine and feces was increased significantly (p〈0.05)from 13.1±1.8mg (mean±SD, 54.6% of total) to 15.3 ±1.1 mg (63.8% of total) by caffeine coadministration. The terminal half-life of ceftriaxone in plasma was shortened from 59 to 47 min, and the area under the plasma drug concentration-time curve (AUC)was reduced from 612 to 516 μg hr/ml Although the peak drug concentrations and the times of peak concentration of ceftriaxone in tissues were not altered by caffeine administration, the elimination of ceftriaxone was increased, as indicated by generally shorter half-lives (decreases ranged from 17.5% in liver to 34.2% in brain) and lower AUCvalues (from 9.0% in heart to 54.5% in brain). These results suggest that caffeine does not alter the protein binding of ceftriaxone, but enhances the elimination of ceftriaxone in the rat.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01059199
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    Drug pharmacokinetics and the carbon dioxide breath test (1986)
    Springer
    Journal of pharmacokinetics and pharmacodynamics 14 (1986), S. 29-49 
    Details
    ISSN: 1573-8744
    Keywords: carbon dioxide ; breath test ; pharmacokinetics ; metabolite ; extraction ratio ; aminopyrine ; caffeine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The interrelationship of the pharmacokinetics of a drug and the expiration of carbon dioxide formed as a metabolite have been studied. The pharmacokinetic characteristics of the drug that affect the usefulness of the carbon dioxide excretion as a measure of liver function were examined by means of computer simulations. The parent drug extraction ratio, fraction demethylated, volume of distribution, and absorption rate of an oral dosage form all contribute to the carbon dioxide breath test result. A drug that would be a useful substrate when the carbon dioxide breath test is used as a probe for changes in liver function should be at least 50% metabolized by demethylation, have a hepatic extraction ratio of 0.2–0.5, and be administered in a form that is rapidly absorbed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01059282
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  • 132
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    Effects of the rate and composition of fluid replacement on the pharmacokinetics and pharmacodynamics of intravenous furosemide (1986)
    Springer
    Journal of pharmacokinetics and pharmacodynamics 14 (1986), S. 495-509 
    Details
    ISSN: 1573-8744
    Keywords: furosemide ; pharmacokinetics ; pharmacodynamics ; fluid replacement
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Effects of differences in the rate and composition of intravenous fluid replacement for urine loss on the pharmacokinetics and pharmacodynamics of furosemide were evaluated using the dog as a model animal. Each of six dogs received 8-hr constant intravenous infusion of 20 mg (15 mg used in one dog) of furosemide with 0% replacement (treatment I), 50% replacement (treatment II), and 100% replacement (treatment III) with lactated Ringer's solution, as well as with 100% replacement with 5% dextrose in water (treatment IV). Most pharmacokinetic parameters, such as plasma clearance, steady-state volume of distribution, mean residence time, and terminal half-life, were essentially the same in all four treatments. Renal clearances and urinary excretion rates of the drug in treatments II–IVwere essentially the same, but about 20% higher than those in treatment I.In spite of the similarities in kinetic properties, diuretic and/or natriuretic effects from furosemide were markedly different among the four treatments. For example, mean 10-hr urine outputs were 646, 1046, 3156, and 1976 ml and mean 10-hr sodium excretions were 87.0, 142, 383, and 97.2 mmole for treatments I–IV,respectively. Except for treatment III,diuresis and/or natriuresis were found to be time-dependent, generally decreasing with time until reaching a low plateau during later hours of infusion. The present findings also showed that (1)no fluid replacement and 100% replacement with 5% dextrose solution both produced the same degree of severe acute tolerance in natriuresis, indicating the insignificance of water compensation in tolerance development; (2)in treatment II,where neutral sodium balance was achieved, the development of acute tolerance in diuresis and natriuresis can mainly be attributed to negative water balance under this special condition; (3)at steady state the hourly diuresis and natriuresis could differ up to about ten times between treatments. Some implications for the kinetic/dynamic relationship or modeling, in the clinical use, and in the bioequivalence evaluation of dosage forms are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01059657
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    Amiodarone pharmacokinetics. I. Acute dose-dependent disposition studies in rats (1986)
    Springer
    Journal of pharmacokinetics and pharmacodynamics 14 (1986), S. 601-613 
    Details
    ISSN: 1573-8744
    Keywords: amiodarone ; pharmacokinetics ; dose-dependent ; rats
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Single intravenous bolus doses of amiodarone hydrochloride of 30, 60, 90 and 120 mg/kg were administered to male Sprague-Dawley rats to determine the effects of dose on amiodarone pharmacokinetics. Serial blood samples and total urine were collected over 48 hr and assayed for amiodarone and desethylamiodarone by HPLC. The blood amiodarone concentration-time curves for the four doses were best described by a triexponential equation with terminal half-lives (t 1/2γ ) ranging from 17 to 20 hr. Over the dose range studied, no changes in γ, t 1/2γ , or central compartment volume (Vc=1.2–1.4 L/kg) were observed. On the other hand, reductions in amiodarone clearance (CL and steady-state volume of distribution (V ss of 44% (17.7 to 10.0 ml/min per kg) and 50% (16.4 to 8.2 L/kg), respectively, were noted as the dose of amiodarone increased. The conversion of amiodarone to desethylamiodarone (fm was dose-independent and amounted to approximately 10% of each amiodarone dose. No amiodarone or desethylamiodarone was detected in the urine of any of the treated animals. The blood-to-plasma concentration ratio of amiodarone was concentration-independent and therefore did not account for the dose-dependent changes in Vss and CL observed. The data suggested that the dose-dependent changes noted were due to an alteration in the volume (s) of the peripheral tissue compartment(s).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01067966
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    Analysis of pethidine disposition in the pregnant rat by means of a physiological flow model (1986)
    Springer
    Journal of pharmacokinetics and pharmacodynamics 14 (1986), S. 381-395 
    Details
    ISSN: 1573-8744
    Keywords: pethidine ; rat ; physiological flow model ; pharmacokinetics ; pregnancy ; scale up ; opiates, GC-MS analytical method ; simulations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The disposition of pethidine (meperidine) in the pregnant rat is described by means of a physiological flow model. The model includes arterial and venous blood, brain, fat, fetal, hepatic, intestinal, muscular, pulmonar, and renal tissues. The concentration-time profiles of pethidine calculated by the model are consistent with experimental data, except for the brain and renal tissues, where the model predicts initially higher concentrations. Simulations are carried out to further explore the contribution from different organs on the kinetics in blood and tissues. The tissue-to-blood partition coefficients vary over a range from 5 to 316, where fat has the lowest and liver the highest after a correction is made due to hepatic extraction. Rapid uptake occurs into highly perfused organs such as brain, kidneys, liver, and lungs, followed by fetus, intestines, muscle, and fat. Data indicate no marked membrane resistance to pethidine of the investigated organs, except for fetal tissues, but rather a perfusion-limited uptake. Simulations suggest that muscles and adipose tissue play an important role in the rat, becoming the major reservoir of drug during the intermediate and terminal elimination phase, respectively. Volume of distribution and the biological half-life agree with reported findings. Pethidine is subject to a high systemic blood clearance, which exceeds the total hepatic blood flow in the rat. No degradation of pethidine is found in blood, and therefore a pulmonary expression for pethidine clearance is added as a potential source of pethidine elimination. The elimination of pethidine after a single i.v. bolus dose is found to be dependent on simulated changes in cardiac output and hepatic blood flow. A simulation is performed with the scaled model to mimic the human concentration-time profiles in maternal blood and brain tissues and fetal tissue during repetitive doses of pethidine.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01059198
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    Saturable Processes Affecting Renal Clearance of Cefixime in Dogs (1986)
    Springer
    Pharmaceutical research 3 (1986), S. 150-155 
    Details
    ISSN: 1573-904X
    Keywords: renal clearance ; cephalosporin ; cefixime ; tubular reabsorption ; saturable protein binding ; pharmacokinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The pharmacokinetics of cefixime, a new orally active cephalosporin, was studied after an intravenous dose of 50 mg/kg to four beagle dogs. Cefixime was shown to exhibit concentration dependent serum protein binding and saturable tubular reabsorption. The drug was excreted mainly in the urine, the net result of glomerular filtration and saturable tubular reabsorption. The experimental results were analyzed by model independent pharmacokinetic equations and with theoretical models describing renal clearance. Modification of the models, based on observed data, was proposed. The experimental methods employed and the pharmacokinetic approach offered in this study can be applied to drugs that exhibit concentration dependent protein binding and saturable renal elimination processes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1016309923717
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    The Effect of Amiodarone on Theophylline Pharmacokinetics in the Rat (1986)
    Springer
    Pharmaceutical research 3 (1986), S. 167-169 
    Details
    ISSN: 1573-904X
    Keywords: amiodarone ; theophylline ; pharmacokinetics ; drug interaction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Amiodarone is an investigational antiarrhythmic agent which has been implicated in reducing the activity of the hepatic mixed-function oxidase system. To evaluate this effect further, two groups of six male Sprague–Dawley rats each received theophylline (6 mg/kg, iv) preceded by either normal saline or amiodarone HC1 (100 mg/kg, iv). Blood samples were obtained serially for a period of 6 hr and the sera were assayed for theophylline by high-pressure liquid chromatography (HPLC). In rats pretreated with amiodarone, a significant 45% reduction in the mean (± SD) systemic clearance [0.057 (0.010) vs 0.031 (0.004) liter/hr/kg, P 〈 0.001] and a greater than 100% increase in the mean elimination half-life [2.03 (0.46) vs 4.29 (0.71) hr, P 〈 0.001] of theophylline were observed. These data demonstrate an acute inhibitory effect of amiodarone on the hepatic microsomal enzyme system.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1016366008696
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    Engineering Targeted In Vivo Drug Delivery. I. The Physiological and Physicochemical Principles Governing Opportunities and Limitations (1986)
    Springer
    Pharmaceutical research 3 (1986), S. 333-344 
    Details
    ISSN: 1573-904X
    Keywords: drug delivery, targeted ; prodrugs ; pharmacokinetics ; pharmacodynamics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract A physiologically based model is presented to aid prediction of the pharmacological benefits to be derived from the administration of a drug as a targeted drug–carrier combination. An improvement in the therapeutic index and an increase in the therapeutic availability are the primary benefits sought. A measure of the former is obtained from the value of the drug targeting index, a newly derived parameter. Both the drug targeting index and the therapeutic availability are directly calculable. The minimum information needed for approximating both parameters is the candidate drug's total-body clearance and some knowledge of the target site's anatomy and blood flow. Drugs with high total-body clearance values that are known to act at target tissues having effective blood flows that are small relative to the blood flow to the normal eliminating organs will benefit most from combination with an efficient, targeted carrier. Direct elimination of the drug at the target site or at the tissue where toxicity originates dramatically improves the drug targeting index value. The fraction of drug actually released from the carrier at both target and nontarget sites can radically affect index values. In some cases a 1% change in the fraction of the dose delivered to the target can result in a 50% change in the drug targeting index value. It is argued that most drugs already developed have a low potential to benefit from combination with a drug carrier. The approach allows one to distinguish clearly those drugs that can benefit from combination with targeted in vivo drug carriers from those drugs that cannot.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1016332023234
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    Influence of Malnutrition on the Disposition of Metronidazole in Rats (1986)
    Springer
    Pharmaceutical research 3 (1986), S. 352-355 
    Details
    ISSN: 1573-904X
    Keywords: malnutrition ; metronidazole ; pharmacokinetics ; rats ; metabolism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The influence of dietary protein deficiency on the disposition of metronidazole and its two major metabolites was examined in male Sprague–Dawley rats fed for 4 weeks on a 23% (control-) or a 5% (low-) protein diet ad libitum. Following an intravenous bolus dose of 10 mg/kg metronidazole hydrochloride, blood samples were obtained serially for a period of 24 hr after drug administration. Serum concentration–time data were analyzed by nonlinear least-squares regression, as well as noncompartmental techniques. The average mean residence time (MRT) was significantly prolonged by 48%, while the systemic clearance (Cl) was decreased by 42% in the protein-deficient rats. Since there was no alteration in the apparent steady-state volume of distribution (V ss), the mean harmonic half-life was increased from 2.9 to 5.0 hr in the protein-deficient rats. Although the percentage of metronidazole recovered as total drug in the urine over 24 hr was not significantly different between the two groups of animals, rats on a low-protein diet excreted a significantly smaller percentage of the administered dose as unchanged metronidazole (mean ± SD, 24.6 ± 3.8 vs 36.5 ± 12%) and a larger percentage (16.7 ± 2.6 vs 8.3 ± 1.8%) as the hydroxylated metabolite. No significant difference in the partial metabolic clearance of the hydroxylated metabolite of metronidazole was seen between the two groups of animals; however, there was a significant decrease in the renal clearance of metronidazole (1.45 ± 0.68 vs 0.55 ± 0.06 ml/min/kg) in the rats fed a low-protein diet. We conclude that the decreased clearance of metronidazole in protein deficiency is a result primarily of the decreased glomerular filtration rate, decreased biliary excretion, and/or increased net tubular reabsorption of metronidazole.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1016433724142
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  • 139
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    Bioavailability of Propranolol After Oral, Sublingual, and Intranasal Administration (1986)
    Springer
    Pharmaceutical research 3 (1986), S. 108-111 
    Details
    ISSN: 1573-904X
    Keywords: propranolol ; intranasal ; sublingual ; absorption ; bioavailability ; pharmacokinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The bioavailability of propranolol was compared after oral, sublingual, and intranasal administration in eight healthy male volunteers. Relative to the bioavailability after intranasal (in) administration, which was previously shown to be nearly complete (F relin = 100%), the sublingual (sl) administration of a standard 10-mg tablet gave a bioavailability of F relsl = 63 ± 22%, while the oral (or) administration yielded only F relor = 25 ± 8%. The serum concentration–time curves of propranolol after sublingual administration resembled those of a sustained-release preparation. This sustained-release phenomenon after the sublingual route is reflected in the mean residence times (MRTs) of propranolol in the body (MRTor = 5.7 ± 1.3 hr, MRTsl - 6.4 ± 1.3 hr, MRTin = 4.6 ± 1.0 hr; mean ± SD; N = 8). MRTs after sublingual administration were significantly longer than after the oral and the intranasal doses (P 〈 0.05 and P 〈 0.002, respectively).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1016345504153
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  • 140
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    Pharmacokinetics and Reversible Biotransformation of Sulfinpyrazone and Its Metabolites in Rabbits. I. Single-Dose Study (1986)
    Springer
    Pharmaceutical research 3 (1986), S. 173-177 
    Details
    ISSN: 1573-904X
    Keywords: sulfinpyrazone ; pharmacokinetics ; reversible metabolism ; single dose
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract In rabbits receiving sulfmpyrazone (SO) and the sulfide metabolite (S) in four separate experiments, the biotransformation of SO into S was found to be reversible, which resulted in approximately parallel terminal disposition profiles for the three major substances in plasma, i.e., SO, S, and the p-OH-sulfide (OH-S). However, differences in disposition kinetics were observed between the intravenous and the peroral administration. The formation of OH-S was independent of both the administered compound and the administration route. The results obtained in the present studies, the previously documented enterohepatic recirculation, and the formation of S by hindgut flora may have implications for studies on sulfinpyrazone, which has been used as an antithrombotic agent.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1016370209604
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  • 141
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    Pharmacokinetics and Reversible Biotransformation of Sulfinpyrazone and Its Metabolites in Rabbits. II. Multiple-Dose Study (1986)
    Springer
    Pharmaceutical research 3 (1986), S. 178-183 
    Details
    ISSN: 1573-904X
    Keywords: sulfinpyrazone ; pharmacokinetics ; reversible metabolism ; multiple dose
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract In crossover studies rabbits were given sulfmpyrazone (SO) and its sulfide metabolite (S) perorally once daily (10 mg/kg) for 5 days. Comparison of the pharmacokinetic parameters obtained after the first and the fifth dose indicates that repeated dosing does not alter disposition kinetics of both SO and S, except that in dosing with S the observed terminal half-life for S is significantly reduced, from 4.59 ± 0.55 to 2.86 ± 0.6 hr (SD). In other studies rabbits were given higher single doses (15, 25, and 50 mg/kg) perorally and comparison was made between these dose sizes and the first dose (10 mg/kg) of multiple administration with S. Some kinetic parameters tended to be altered in a nonlinear fashion, and greater intersubject variations were observed because of the dose increase, while oxidation to SO or p-hydroxylation to OH-S from S was not significantly altered.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1016322326443
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  • 142
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    Pharmacoclinical data on high dose medroxyprogesterone acetate in advanced breast cancer (1986)
    Springer
    Breast cancer research and treatment 8 (1986), S. 161-163 
    Details
    ISSN: 1573-7217
    Keywords: medroxyprogesterone acetate ; pharmacokinetics ; response ; toxicity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01807705
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  • 143
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    Hauptgruppenelement-Übergangsmetall-Mehrfachbindungen, IV. Katalytische Assistenz von [Cp(CO)3Mo]2 bei der Aggregation von Metallo-arsanen über Arsen-Metall-Doppelbindungskomplexe (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 378-382 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Main Group Element Transition Metal Multiple Bonds, IV. Catalytic Assistance by [Cp(CO)3Mo]2 in the Aggregation of Metallo-arsanes via Arsenic Metal Double Bond Complexes2)The metallo-arsanes Cp(CO)3M—AsMe2 (1a, b) (M = Mo, W) are converted to the double arsenido-bridged dinuclear complexes [(μ-AsMe2)Mo(CO)2Cp]2 (3a, b) in the presence of [Cp(CO)3Mo]2. Due to the unusual mild conditions of aggregation the intermediate formation of the double bonded species Cp(CO)2M=AsMe2 (2a, b) is postulated. The crystal structure of 3a is reported, which shows mutual trans arrangement of the cyclopentadienyl and CO ligands.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190133
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  • 144
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    Aliphatische Flüssigkristalle, 7. Einige mesogene Tercyclohexylderivate (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 387-400 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Aliphatic Liquid Crystals, 7. Some Mesogenic Tercyclohexyl DerivativesStarting from bicyclohexyl-4-one 1 the tercyclohexyl-3-one 6 is synthesized via the acetyl derivatives 3a,b. Methoxycarbonylation of 6 gives the keto ester 12 which on the one hand is tranformed to the esters 15a,b and 17 - 20 and the nitriles 21a,b, on the other hand to the methylated keto esters 23a,b and 24a,b. From 23a the ester 26 with an axial 1-methyl group is obtained. Nearly all the products are mesogenic.
    Notes: Aus dem Bicyclohexyl-4-on 1 wird über die Acetylderivate 3a,b das Tercyclohexyl-3-on 6 aufgebaut, daraus durch Methoxycarbonylierung der Ketoester 12, der einerseits zu den Estern 15a,b und 17 - 20 und den Nitrilen 21a,b, andererseits zu den methylierten Ketoestern 23a,b und 24a,b umgesetzt wird. Aus 23a erhält man den Ester 26 mit axialer 1-Methylgruppe. Fast alle Produkte sind mesogen.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190202
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  • 145
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    Beiträge zur Chemie des Bors, 169. Sterisch anspruchsvolle N-Lithioaminoborane: Reagentien zur Synthese symmetrisch und unsymmetrisch substituierter Diborylamine (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1361-1373 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Boron, 169. Sterically Demanding N-Lithioaminoboranes: Reagents for the Synthesis of Symmetrically and Unsymmetrically Substituted DiborylaminesN-Metalation of R2BNH2 or R2BNMeH yields lithium amides R2BNR′Li with sterically demanding R groups (R = tBu, iPr). These compounds are synthons for symmetrically or unsymmetrically substituted diborylamines as well as for B-functional diborylamines. NMR data reveal the conformation of these diborylamines. Compounds of the type tBu2B—NMe—BR2 contain tBu2B groups whose BC2 plane stands nearly orthogonal to the B2NC skeleton. In contrast, the BRX group in diborylamines of the type tBu2B—NH—BRX is strongly twisted with respect to the B2NH plane.
    Notes: Durch N-Metallierung erhältliche Lithiumamide R2BNR′Li mit sperrigen Substituenten R = tBu, iPr eignen sich sowohl zur Darstellung symmetrisch und unsymmetrisch substituierter Diborylamine als auch zur Gewinnung B-funktioneller Diborylamine. Kernresonanzspektroskopische Untersuchungen zeigen, daß Diborylamine tBu2B—NMe—BR2 eine tBu2B-Gruppe enthalten, deren BC2-Ebene weitgehend orthogonal zur B2NC-Gerüstebene steht. In Diborylaminen tBu2B—NH—BRX ist hingegen die BRX-Gruppe gegen die B2NH-Ebene verdrillt.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190423
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  • 146
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    Mehrfachbindungen zwischen Hauptgruppenelementen und Übergangsmetallen, XXV. Aufbau und Reaktivität von Se1- und Se2-Brücken in Organochrom-Komplexen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1437-1440 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Multiple Bonds Between Main Group Elements and Transition Metals, XXV. Synthesis and Reactivity of Se1- and Se2-Bridges in Organochromium CompoundsReaction of the ionic complex K[(η5-C5Me5)Cr(CO)3] (1) with selenium(I) with selenium(I) chloride, Se2Cl2, yields the diselenium compounds 2 of composition (η5-C5Me5)Cr(CO)5Se2 which is converted to the Se1 derivative (μ-Se)[η5-C5Me5)Cr2(CO)2]2 (3) with triphenylphosphane. 3 exhibits a linear, multiple bonded CrSeCr core structure. Reaction of 2 with diazomethane gives the novel mononuclear, paramagnetic selenoformaldehyde complex (η5-C5Me5)-Cr(CO)2(SeCH2) (4).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190430
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  • 147
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    Masthead (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986) 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190501
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  • 148
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    N-tert-Butylpivalohydroxamsäure: s-trans-Konformation und H-Brückenbindungen im Kristall (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1441-1444 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: N-tert-Butylpivalohydroxamic Acid: s-trans-Conformation and H-Bonding in the CrystalIt is shown by an X-ray crystal structure analysis that, in the crystal, teh title compound has the s-trans-conformation and the molecules are linked by strong intermolecular H-bonds to linear chains.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190431
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  • 149
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    Synthesen von 2,6,7-Triazabicyclo[2.2.2]oct-2-en-5,8-dionen und 4(3H)-Pyrimidinonen durch 1,4-Dipolare Cycloadditionen von Pyrimidinium-4-olaten an Nitrile (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1445-1454 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses of 2,6,7-Triazabicyclo[2.2.2]oct-2-ene-5,8-diones and 4(3H)-Pyrimidinones via 1,4-Dipolar Cycloaddition Reactions of Pyrimidinium-4-olates to NitrilesThe 3,6-dihydro-6-oxo-1-pyrimidinium-4-olate 1a, which carry no substituent in the 2 position, undergoes 1,4-dipolar cycloaddition reactions with ethyl cyanoformate (2a) and benzoyl cyanide (2b) to produce novel bicyclic primary adducts 3a, b, respectively, which at higher temperature fragment into 4(3H)-pyrimidinones 4a, b with elimination of phenyl isocyanate. However, pyrimidinium-4-olates 1b - h or 5, which are substituted in the 2 position, react directly with nitriles 2a - c to form high yields of 4(3H)-pyrimidinone derivatives of type 4 or 7, respectively. Furthermore, the reactions of 1a with isocyanic acid as well as with cyan amide are described.
    Notes: Das in 2-Position unsubstituierte 3,6-Dihydro-6-oxo-1-pyrimidinium-4-olat 1a geht mit Cyanameisensäure-ethylester (2a) und Benzoylcyanid (2b) 1,4-Dipolare Cycloadditionen zu neuen bicyclischen Primäraddukten 3a bzw. b ein, die bei höherer Temperatur unter Phenylisocyanat-Abgabe in 4(3H)-Pyrimidinone 4a, b fragmentieren. Dagegen reagieren die in 2-Stellung substituierten Pyrimidinium-4-olate 1b - h oder 5 mit Nitrilen 2a - c in hohen Ausbeuten direkt zu den 4(3H)-Pyrimidinon-Derivaten vom Typ 4 bzw. 7. Weiterhin werden die Reaktionen von 1a mit Isocyansäure sowie mit Cyanamid beschrieben.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190502
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    Über sterisch gehinderte freie Radikale, XV. Das erste unsymmetrische Dimere aus zwei stabilen Radikalen: 3-(tert-Butylphenylmethylen)-6-(triphenylmethyl)-1,4-cyclohexadien aus tert-Butyldiphenylmethyl und Triphenylmethyl (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2006-2012 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Sterically Hindered Free Radicals, XV. The First Unsymmetrical Dimer from Two Different Stable Radicals: 3-(tert-Butylphenylmethylene)-6-(triphenylmethyl)-1,4-cyclohexadiene from tert-Butyldiphenylmethyl and TriphenylmethylThe quinonoid title compound 6 is formed in an equilibrium to 95% and can be isolated, when the two title radicals 1 and 3 are generated in solution. The reason for this is the sterically less strained position of the bulky tBu group at the sp2-C atom of the methylene group. The structure of 6 is proved by 1,5-H migration giving 8 and autoxidation of the latter at -10°C giving tBuOH and 4-tritylbenzophenone (12). The synthesis of several analogous compounds are described.
    Notes: Die chinoide Titelverbindung 6 entsteht im Gleichgewicht zu 〉95% und kann isoliert werden, wenn die beiden Titelradikale 1 und 3 in Lösung erzeugt werden. Ursache hierfür ist die räumlich günstigere Unterbringung der sperrigen tBu-Gruppe am sp2-C-Atom der Methylengruppe. Die Struktur von 6 wird durch 1,5-H-Verschiebung zu 8 sowie dessen Autoxidation bei -10°C zu tBuOH und 4-Tritylbenzophenon (12) bewiesen. Synthesen analoger Verbindungen werden beschrieben.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190621
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    Der Einfluß von Phenylgruppen auf die Homokonjugation im Bicyclo[3.2.1]octa-3,6-dien-2-yl-Anion. Eine 13C-NMR-Studie (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2025-2049 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Effect of Phenyl Groups on the Homoconjugation in the Bicyclo[3.2.1]octa-3,6-dien-2-yl Anion. A 13C NMR StudyThe effects of deuterium atoms in the positions 2 and 4 of exo-6-bromo- (11) and endo-6-methoxytricyclo[3.2.1.02,7]oct-3-ene (12) as well as exo-4-methoxybicyclo[3.2.1]octa-2,6-diene (13) on their 13C chemical shifts are in line with the previous interpretation of the effects in correspondingly deuterated bicyclo[3.2.1]octa-3,6-dien-2-yl anions 1, and thus provide evidence for the homoconjugative interaction in 1. 3-Phenylbicyclo[3.2.1]octa-2,6-diene (16) and endo- (19a) as well as exo-4-phenylbicyclo[3.2.1]octa-2,6-diene (19b) have been prepared from bicyclo[3.2.1]oct-6-en-3-one (14) and bicyclo[3.1.0]hex-2-ene-endo-6-carbaldehyde (17), respectively. 2,4-Diphenylbicyclo[3.2.1]octa-2,6-diene (6) and 19a, b were deprotonated by methyllithium and n-butyllithium, respectively, whereas the proton abstraction from tricyclo[6.3.1.02,7]dodeca-2,4,6,9-triene (4) and from 16 required potassium tert-butoxide/n-butyllithium. As products the corresponding bicyclo[3.2.1]octa-3,6-dien-2-yl anion derivatives have been identified. By means of potassium tert-butoxide/n-butyllithium 19a, b were converted into 21K, i.e. the anion with K+ as counterion. The NMR spectra of 21Li turned out to depend upon the temperature in the range between +45 and -30°C in contrast to those of 21K. The 13C NMR spectra of the anions and of the corresponding hydrocarbons are discussed in detail in relation to the spectra of the unsubstituted species 1 and 2. In particular, the wide variations of the chemical shifts of C-6,7 depending upon the substituents of the allylic moiety of the bicyclo[3.2.1]octa-3,6-dien-2-yl anion system give strong support for the bishomoaromatic nature of these anions.
    Notes: Die Effekte von Deuteriumatomen in den Positionen 1 und 4 von exo-6-Brom- (11) und endo-6-Methoxytricyclo[3.2.1.02,7]oct-3-en (12) sowie exo-4-Methoxybicyclo[3.2.1]octa-2,6-dien (13) auf deren 13C-chemische Verschiebungen stützen die frühere Interpretation der Effekte bei entsprechend deuterierten Bicyclo[3.2.1]octa-3,6-dien-2-yl-Anionen 1 und belegen so die homokonjugative Wechselwirkung in 1.  -  Ausgehend von Bicyclo[3.2.1]oct-6-en-3-on (14) und Bicyclo[3.1.0]hex-2-en-endo-6-carbaldehyd (17) stellte man 3-Phenyl- (16) bzw. endo-4-Phenyl-(19a) und exo-4-Phenylbicyclo[3.2.1]octa-2,6-dien (19b) dar. 2,4-Diphenylbicyclo[3.2.1]octa-2,6-dien (6) und 19a, b wurden mit Methyllithium bzw. n-Butyllithium, Tricyclo[6.3.1.02,7]dodeca-2,4,6,9-tetraen (4) sowie 16 mit Kalium-tert-butoxid/n-Butyllithium deprotoniert, wobei die entsprechenden Bicyclo[3.2.1]octa-3,6-dien-2-yl-Anionderivate 7, 21Li, 5 und 22 entstanden. Aus 19a, b wurde mit Kalium-tert-butoxid/n-Butyllithium auch 21K, d. h. das zugehörige Anion mit K+ als Gegenion erhalten. Die NMR-Spektren von 21Li erwiesen sich im Gegensatz zu jenen von 21K im Bereich von +45 bis -30°C als temperaturabhängig. Die 13C-NMR-Spektren der Anionen und der zugehörigen Kohlenwasserstoffe werden im Vergleich mit den Spektren der unsubstituierten Verbindungen 1 und 2 ausführlich diskutiert. Insbesondere die starken Variationen der chemischen Verschiebungen von C-6,7 in Abhängigkeit von den Substitutenten am Allylteil des Bicyclo[3.2.1]octa-3,6-dien-2-yl-Anionsystems bieten ein starkes Argument für die bishomoaromatische Natur dieser Anionen.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190623
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    Synthese und physikalische Eigenschaften neuer 1,3-Dithiolylium-4-methanide und 1,3-Thiazolium-5-methanide (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2094-2103 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Physical Properties of Novel 1,3-Dithiolylium-4-methanides and 1,3-Thiazolium-5-methanidesThe synthesis and physical properties of the novel title compounds of type 9 from carboxylic acid derivatives 3 and CH acidic compounds 4 are described.
    Notes: Die Synthese und physikalischen Eigenschaften der neuen Titelverbindungen vom Typ 9 aus Carbonsäure-Derivaten 3 und CH-aciden Verbindungen 4 werden beschrieben.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190704
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    Metallaheterocumulene, IV. 2-Azaallyliden-Komplexe  -  neuartige Verbindungen mit einem gewinkelten CNCR2-Fragment als Komplexligand (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2080-2093 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Metallaheterocumulenes, IV. 2-Azaallylidene Complexes  -  Novel Compounds with a Bent CNCR2 Fragment as Complex Ligand(2-Azoniaallenylidene)pentacarbonyltungsten tetrabromoaluminate complexes [(CO)5W(CNCR2)]+AlBr4- (2-AlBr4) (CR2=C(C6H4Br-4)2 (a), CPh2 (b), C(C6H4OMe-4)2 (c), C(C6H4)2O (d), C(2,4,6-C6H2Me3)2 (e)) Which are synthesized by the reaction of (CO)5W[C(OEt)N=CR2] (1) with AlBr3, react with freshly distilled tetrahydrofuran to give neural trans-bromo(2-azaallylidene) complexes trans-Br(CO)4W(CNCR2) (3) and small amounts of (CO)5W—C≡N—[CR2]2—N≡C—W(CO)5 (4). The compounds 4 correspond to the product of a reductive dimerization of two cations 2. If 1b (or the corresponding methoxy compound 5) reacts with BBr3 instead of AlBr3/THF 4b is the main product. The spectroscopic data of 3 and the results of an X-ray analysis of 3b show that the replacement of a CO ligand in the cations 2 by Br- with formation of 3 results in a drastic change of the bonding situation within the CNCR2 ligand. 3a-e are the first compounds in which a strongly bent CNCR2 fragment functions as a complex ligand. The aminocarbyne complex trans-Br(CO)4W≡CNPh2 (7) was synthesized by BBr3-induced fragmentation of (CO)5W[C(NPh2)N=C(Ph)OMe] (6).
    Notes: (2-Azoniaallenyliden)pentacarbonylwolfram-tetrabromoaluminat-Komplexe [(CO)5W(CNCR2)]+AlBr4- (2-AlBr4) (CR2=C(C6H4Br-4)2 (a), CPh2 (b), C(C6H4OMe-4)2 (c), C(C6H4)2O (d), C(2,4,6-C6H2Me3)2 (e))  -  darstellbar durch Umsetzung von (CO)5W[C(OEt)N=CR2] (1) mit Albr3  -  reagieren mit frisch destillierten Tetrahydrofuran zu neutralen trans-Bromo(2-azaallyliden)-Komplexen trans-Br(CO)4W(CNCR2) (3) und wenig (CO)5W—C≡N—[CR2]2—N≡C—W(CO)5 (4). Die Verbindungen 4. entsprechen dem Produkt einer reduktiven Dimerisierung zweier Kationen 2. 4b wird zum Hauptprodukt der Umsetzung, wenn 1b (oder der entsprechende Methoxy-Komplex 5) mit BBr3 anstatt AlBr3/THF umgesetzt wird. Wie die spektroskopischen Daten von 3 sowie die Ergebnisse der an 3b durchgeführten Röntgenstrukturanalyse zeigen, führt der Austausch eines CO-Liganden in den Kationen 2 gegen Br- unter Bildung von 3 zu einer drastischen Veränderung der Bindungsverhältnisse im CNCR2-Liganden. 3a-e sind die ersten Verbindungen, in denen ein stark gewinkeltes CNCR2-Fragment als Komplexligand fungiert. Durch BBr3-induzierte Fragmentierung von (CO)5W[C(NPh2)N=C(Ph)OMe] (6) wurde der Aminocarbin-Komplex trans-Br(CO)4W≡CNPh2 (7) dargestellt.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190703
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  • 154
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    Heterocyclische β-Enaminoester, 41. Vinylogieprinzip bei 6,7-Dihydro-1H-azepinen; Cycloaddition und neuartige Umlagerung zu 2,3,3a,7a-Tetrahydroindolen.  -  Thermische [2 + 2]-Cycloadditionen mit 4-R-TAD (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2114-2126 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Heterocyclic β-Enamino Esters, 41. Vinylogeous Principle on 6,7-Dihydro-1H-azepines; Cycloaddition and Novel Rearrangement to 2,3,3a,7a-Tetrahydroindoles.  -  Thermal [2 + 2]-Cycloadditions with 4-R-TADThe conjugated π-Systems of 6,7-dihydrooxepines, -thiepines, and -azepines (1-5) show a remarkable alternance of their 13C NMR shifts. In a cycloaddition-ring enlargement sequence the 6,7-dihydroazepine 3 reacts with acetylenedicarboxylates at the 4,5-double bond to afford first the intermediary 8,9-dihydro-1H-azonines 6B. These give in turn the indoles 7a,b via thermal 6π-electron cyclization. Under subsequent rearrangement 2,3,3a,7a-tetrahydroindoles 8a,b are formed. The structure of 8a is established by X-ray diffraction. In a polar [2 + 2]-cycloaddition 4-R-1,2,4-triazoline-3,5-dione (4-R-TAD) gives with 3 and 5 the [1,2,4]triazolo[1′,2′:1,2]diazet-[3,4-d]azepines 10a-d and 11a,b resp., and with the bis-TAD 12 the 2:1-adduct 13. Treatment of 10a with phenyl isocyanate originates the carbodiimide 14 which is converted with basic ring closure into the pyrimido[4,5-b]azepine 15.
    Notes: 6,7-Dihydrooxepine, -thiepine und -azepine (1-5) zeigen eine ausgeprägte Alternanz ihrer 13C-NMR-Verschiebungen im konjugierten π-System. Das 6,7-Dihydroazepin 3 reagiert mit Acetylendicarbonsäureestern zunächst unter Cycloaddition-Ringerweiterung an der 4,5-Doppelbindung zu den intermediären 8,9-Dihydro-1H-azoninen 6b. Diese ergeben sogleich unter thermischem 6π-Elektronenringschluß die Indole 7a,b. Nach erneuter Umlagerung entstehen 2,3,3a,7a-Tetrahydroindole 8a,b; die Konstitution von 8a wird durch Röntgenstrukturanalyse ermittelt. Mit 4-R-1,2,4-Triazolin-3,5-dionen (4-R-TAD) entstehen aus 3 und 5 in polarer [2 + 2]-Cycloaddition die [1,2,4]Triazolo[1′,2′:1,2]diazet[3,4-d]azepine 10a-d und 11a,b mit dem Bis-TAD 12 das 2:1-Addukt 13. 10a ergibt mit Phenylisocyanat das Carbodiimid 14 und beim basischen Ringschluß das Pyrimido[4,5-b]azepin 15.
    Additional Material: 5 Tab.
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    URL: http://dx.doi.org/10.1002/cber.19861190706
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  • 155
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    Neue Reagenzien, XXXVII. (α-Lithioalkyl)diphenylarsanoxide: Synthese und Anwendung zur indirekten nucleophilen Haloalkylierung (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2135-2142 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: New Reagents, XXXVII. (α-Lithioalkyl)diphenylarsane Oxides: Synthesis and Application for the Indirect Nucleophilic HaloalkylationDue to ready accessibility and high nucleophilicity (α-lithioalkyl)diphenylarsane oxides (2) are favorable reagents for the synthesis of many organoarsenic compounds. In organic synthesis they are recommendable as reagents for indirect nucleophilic haloalkylation reactions (Hal=Cl, Br, I).
    Notes: (α-Lithioalkyl)diphenylarsanoxide (2) sind wegen ihrer bequemen Zugänglichkeit und hohen Nucleophilie günstige Reagenzien zur Darstellung zahlreicher Organoarsenverbindungen. In der organischen Synthese sind sie als Reagenzien für indirekte nucleophile Haloalkylierungen (Hal=Cl, Br, I) empfehlenswert.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190708
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  • 156
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    Synthesen mit Cyclobutadienen, 13. Azapentafulvene aus 2,3,4-Tri-tert-butylcyclobutadien-1-carbonsäureestern und Isonitrilen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2159-2172 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthese with Cyclobutadienes, 13. Azapentafulvenes from 2,3,4-Tri-tert-butylcyclobutadiene-1-carboxylic Esters and IsonitrilesFrom kinetically stabilized cyclobutadienes 6a and b and isonitriles 7a-c the azapentafulvenes 9a-d are obtained. In contrast, 6a reacts with 7d exclusively to form the constitution isomeric azapentafulvene 11e. Both isomers (9f and 11f) are realized in the reaction of 6a with 7e. The structural assignment of the isomers 9 and 11 is based on 13C NMR investigations as well as on an X-ray analysis performed for 9a. Hydrolysis of 9 and 11 yields the tri-tert-butyl substituted cyclopentadienones 20a,b and 21. By photochemical means 21 is transformed into the isomer 20a, which can also be obtained directly from the cyclobutadiene 6a and carbon monoxide.
    Notes: Aus den kinetisch stabilisierten Cyclobutadienen 6a bzw. b und den Isonitrilen 7a-c erhält man die Azapentafulvene 9a-d. Im Gegensatz dazu reagiert 6a mit 7d ausschließlich unter Bildung des konstitutionsisomeren Azapentafulvens 11e. Beide Möglichkeiten (9f und 11f) werden bei der Umsetzung von 6a mit 7e wahrgenommen. Die Strukturzuordnung der Isomeren 9 und 11 beruht auf 13C-NMR-Untersuchungen sowie auf der Röntgenstrukturanalyse für 9a. Hydrolyse von 9 und 11 macht die tri-tert-butylsubstituierten Cyclopentadienone 20a,b und 21 zugänglich. Photochemisch läßt sich 21 in das Isomere 20a umwandeln, das auch unmittelbar aus dem Cyclobutadien 6a und Kohlenmonoxid erhalten werden kann.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190711
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  • 157
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    Enantioselective diastereospecific synthesis of anti-α-alkyl-β-hydroxy esters through cuprate opening of glycidic esters (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2178-2190 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Enantioselektive diastereospezifische Synthese von anti-α-Alkyl-β-hydroxycarbonsäureestern durch Cuprat-Ringöffnung von GlycidesternEine über die Zwischenglieder 4-7 ablaufende diastereospezifische Kettenverlängerung von Aldehyden 1 zu anti-α-Alkyl-β-hydroxyestern 2 wird beschrieben. Durch Verwendung der Sharpless-Epoxidierung kann 2 mit Enantiomerenüberschüssen von 〉90% in Form beider Antipoden erhalten werden.
    Notes: A diastereospecific chain elongation of the aldehydes 1 of anti-α-alkyl-β-hydroxy esters 2 via the intermediates 4-7 is described. By means of the Sharpless epoxidation, 2 may be obtained with 〉90% ee in either enantiomer.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190713
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  • 158
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    Stereoselektive Aldolreaktion mit chiralen sekundären Acetamiden (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2191-2207 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Stereoselective Aldol Reaction with Chiral Secondary AcetamidesThe deprotonated acetamides 4a-c und 5a-c are added to prochiral carbonyl compounds. The influence of the solvent, of the reaction temperature, and of the enolate gegenion on the ratio of the isomeric products 8/9, 18/19, and 26/27, respectively, are studied. The highest degrees of diastereoselectivity are observed, when the titanium enolate of the acetamide 4a or the threefold deprotonated N-acetyl-α-phenylglycinol (5a) is used. The diastereomers 18a-d, formed in excess in the addition of 5a to aldehydes, are isolated in a pure form by a single recrystallization, and afford the enantiomerically pure β-hydroxy carboxylic acids 3a-d. Thereby, the chiral auxiliary, α-phenylglycinol (14), is recovered.
    Notes: Die deprotonierten Acetamide 4a-c und 5a-c werden an prochirale Carbonylverbindungen addiert. Dabei wird der Einfluß von Lösungsmittel, Temperatur und Enolat-Gegenion auf das jeweilige Verhältnis der isomeren Produkte 8/9, 18/19 und 26/27 untersucht. Die höchsten Diastereoselektivitäten lassen sich mit dem Titan-enolat des Amids 4a und dem dreifach deprotonierten N-Acetyl-α-phenylglycinol (5a) erzielen. Die bei der Addition von 5a an Aldehyde im Überschuß gebildeten Diastereomeren 18a-d können durch einmaliges Umkristallisieren rein erhalten werden und liefern nach alkalischer Hydrolyse die enantiomerenreinen β-Hydroxycarbonsäuren 3a-d. Dabei wird der chirale Hilfsstoff, α-Phenylglycinol (14), zurückgewonnen.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190714
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  • 159
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    Synthesis of ketene aminals with an imidazolidine ring by condensation of 4,5-dihydro-2-(methylithio)-1H-imidazoles with active methylene compounds and some addition and cyclocondensation reactions (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2208-2219 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthese von Ketenaminalen mit Imidazolidinring durch Kondensation von 4,5-Dihydro-2-(methylthio)-1H-imidazolen mit CH-aciden Methylenverbindungen und einige Additions-und Cyclokondensations-Reaktionen4,5-Dihydro-2-(methylthio)-1H-imidazole 1a, b reagieren mit aktiven Methylenverbindungen 2a-f unter Eliminierung von Methanthiol zu den entsprechend substituierten Methylenimidazolidinen 3a-f und 4c-f. Die Verbindungen 2g-j, die eine aktivere Carbonylgruppe enthalten, ergeben mit 1a unter Eliminierung einer Methylthio- und Acylgruppe 3g-i. 3a, g-i reagieren mit Estern ungesättigter Säuren in einer Additions- und Cyclokondensations-Sequenz zu den entsprechenden Imidazo[1,2-a]pyridinen 5,6 und 7, ergeben aber mit Azodicarbonsäure-diethylester nur die Additionsprodukte 8.
    Notes: The 4,5-dihydro-2-(methylthio)-1H-imidazoles 1a,b react with active methylene compounds 2a-f to afford the corresponding substituted methyleneimidazolidines 3a-f and 4c-f by elimination of methanethiol. The reaction of compounds 2g-j, which contain a more active carbonyl group, with 1a gives 3g-i by elimination of a methylthio group as well as an acyl group, too. 3a,g-i react with esters of α,β-unsaturated acids to afford the corresponding imidazo[1,2-a]pyridines 5,6, and 7 in an addition and cyclocondensation reaction sequence, but with diethyl azodicarboxylate only to give the addition product 8.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190715
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    Desaminierungsreaktionen, 43. Zum Einfluß von Trifluormethylgruppen auf die Reaktionen aliphatischer Diazonium-Ionen und Carbokationen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2233-2248 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Deamination Reactions, 43. The Effect of Trifluoromethyl Groups on the Reactivity of Aliphatic Diazonium Ions and CarbocationsVarious trifluoroalkanamines (9, 26, 35, 38, 45, 56, and 67) have been prepared and diazotized (water, pH 3.5) to probe the effect of trifluoromethyl groups on the reactivity of aliphatic diazonium ions. The product distributions reveal that α-CF3 groups enhance inverting displacement and enforce rearrangements (hydride shifts) separating the positive charge from CF3. Migrations of the positive charge from the β- to the γ-position are less strongly promoted than those from α to β. Enhancement factors of ca. 15 (α → β) and 4 (β → γ) may be derived by comparison with analogous alkanediazonium ions. The positive charge does not migrate in the reverse direction (β → α) except for minor amounts of a pinacolic rearrangement (68 → 7). A migration of the positive charge from γ to β has been detected with 36 but a tenfold decrease as compared to the analogous butanediazonium ion 37 is indicated. All observations are reasonably explained in terms of the relative stabilites of the intermediate trifluoroalkyl cations.
    Notes: Eine Reihe von Trifluoralkanaminen (9, 26, 35, 38, 45, 56 und 67) wurde dargestellt und diazotiert (Wasser, pH 3.5), um den Einfluß von Trifluormethylgruppen auf die Reaktionsweise aliphatischer Diazonium-Ionen zu untersuchen. Die Produktverteilungen zeigen, daß α-CF3-Gruppen die invertierende Substitution verstärken und Umlagerungen (Wasserstoffverschiebungen) fördern, welche die positive Ladung von der CF3-Gruppe trennen. Die Wanderung der positiven Ladung von der β- zur γ-Position wird weniger stark gefördert als die von α nach β. Aus dem Vergleich mit analogen Alkandiazonium-Ionen lassen sich Beschleunigungsfaktoren von ca. 15 (α → β) und 4 (β → γ) ableiten. In umgekehrter Richtung (β → α) wandert die positive Ladung nicht, abgesehen von einem kleinen Anteil Pinakol-Umlagerung (68 → 7). Eine Ladungsverschiebung von der γ- zur β-Position wurde bei 36 gefunden; im Vergleich zum analogen Butandiazonium-Ion 37 ist sie um den Faktor 10 verringert. Alle Beobachtungen sind im Einklang mit der relativen Stabilität der intermediären Trifluoralkyl-Kationen.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190717
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  • 161
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    Neuartige 2,6-disubstituierte Azulene (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2272-2288 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Novel 2,6-Disubstituted AzulenesMethods are described to introduce varying residues into 2- and 6-positions of azulene, starting from diethyl 6-bromo-2-methoxy-1,3-azulenedicarboxylate (1). 2-Substitution is achieved by Grignard reaction or exchange of the alkoxy group and by aldol condensation of 2-methyl compounds whereas 6-substitution is conducted by nucleophilic displacement and by homo- and hetero-aromatic coupling. Consecutive dealkoxycarbonylation yields azulenes 20 with free 1,3-positions. Biazulenes 9a-c and 201, 20m, styryl- and bis(styryl)-azulenes 15-18 and 20i-k, and finally the azulenedialdehyde 19 are novel compounds which were difficult to prepare or were inaccessible so far.
    Notes: Ausgehend von 6-Brom-2-methoxy-1,3-azulendicarbonsäure-diethylester (1) werden Methoden zur Einführung unterschiedlicher Reste in 2- und 6-Position entwickelt. 2-Substitution gelingt durch Grignard-Reaktion oder Austausch der Alkoxygruppe sowie durch Aldol-Kondensation von 2-Methylverbindungen, während 6-Substitution durch nucleophilen Austausch und durch Homo- und Kreuz-Aromaten-Kupplungen erfolgt. Anschließende Dealkoxycarbonylierung erbringt Azulene 20 mit freien 1,3-Stellungen. Die Biazulene 9a-c und 201, 20m, die Styryl- und Bis(styryl)azulene 15-18 und 20i-k sowie der Azulendialdehyd 19 sind Verbindungen, die bisher schwierig oder nicht zugänglich waren.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190720
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    Zur Frage der Stellungsisomerie bei disubstituierten Bullvalenen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2339-2349 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Concerning the Question of Positional Isomerism in Disubstituted BullvalenesWe report about 15 new disubstituted bullvalenes (2, 4, 5, 11, 12, 14-20, 22-24) and discuss their substitution pattern together with 9 known species (1, 3, 6-10, 13, 21). The results which are partly unexpected are put together phenomenologically. We have no reasonable explanation for some results, i.e. only a few substituents with „complementary“ properties like the pair CH2OH/Br or CH3/CN in compounds 16 and 18, respectively, prefer a vicinal arrangement at a double bond.
    Notes: Wir berichten über 15 neue disubstituierte Bullvalene (2, 4, 5, 11, 12, 14-20, 22-24) und diskutieren ihr Substitutionsmuster gemeinsam mit dem von 9 bekannten Vertretern (1, 3, 6-10, 13, 21). Die teilweise unerwarteten Ergebnisse werden phänomenologisch geordnet. Für einige Befunde fehlen befriedigende Erklärungen. So bevorzugen z. B. nur manche Substituenten mit „komplementären“ Eigenschaften wie das Paar CH2OH/Br oder CH3/CN in den Verbindungen 16 bzw. 18 eine vicinale Anordnung an der Doppelbindung.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190724
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    Zur Regio- und Stereoselektivität neuer thermischer [3 + 2]-Cycloadditionen mesoionischer 1,3-Oxathiol-4-one an Alkine und Alkene (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2317-2338 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the Regio- and Stereoselectivity of Novel Thermal [3 + 2] Cycloaddition Reactions of Mesonionic 1,3-Oxathiol-4-ones to Alkynes and AlkenesAs potential carbonyl ylides, the 1,3-oxathiolyium-4-olates 1c or 1d combine with dibenzoylacetylene or 1-(diethylamino)-1-propyne via nonisolable [3 + 2] primary adducts of type 2, which release COS to give the furan derivatives 3a or b, respectively. On the other hand, some representative of 1 reacts with symmetrically and unsymmetrically substituted olefinic substrates with regio- and/or stereoselective formation of the isolable [3 + 2] primary adducts 4-16. In the example of the reactions of 1c with trans- and cis-cyclooctene, the stereospecificities and the competition constant are determined. Furthermore, the thermolyses of the cycloadducts 4b,5,6, and 7a,b are investigated. The addition directions, derived from the FMO and PMO theory, are compared with the experimentally realized regiochemistry.
    Notes: Als potentielle Carbonyl-ylide vereinigen sich die 1,3-Oxathiolylium-4-olate 1c oder 1d mit Dibenzoylacetylen oder 1-(Diethylamino)-1-propin über nicht isolierbare [3 + 2]-Primäraddukte vom Typ 2 unter COS-Abspaltung zu Furan-Derivaten 3a bzw. b. Demgegenüber reagieren einige Vertreter von 1 mit symmetrisch und unsymmetrisch substituierten olefinischen Substraten regio- und/oder stereoselektiv zu isolierbaren [3 + 2]-Primäraddukten 4-16. Am Beispiel der Umsetzung von 1c mit trans- und cis-Cycloocten werden die Stereospezifitäten und die Konkurrenzkonstante ermittelt. Weiterhin werden die Thermolysen der Cycloaddukte 4b, 5, 6 und 7a,b untersucht. Die aus der FMO- und PMO-Theorie abgeleiteten Additionsrichtungen werden mit der experimentell realisierten Regiochemie verglichen.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190723
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    Synthese und Reaktion von α-(Dimethylamino)alkanaldimethylhydrazonen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2397-2413 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Reaction of α-(Dimethylamino)alkanal DimethylhydrazonesSeveral α-(dimethylamino)aldehyde hydrazones of the general structure 11 have been obtained by alkylation of the lithium salt of 9 or by addition of Grignard reagents to 15 or 17. The compounds react with acyl chlorides to give hydrazones of unsaturated aldehydes. The same products 27 are obtained by thermal degradation of the ammonium salts 26. In the hydrazonoammonium salts 26a, g the trimethylammonium group can be substituted by a variety of nucleophiles (→ 34-39).
    Notes: Verschieden substituierte α-(Dimethylamino)aldehyd-hydrazone der allgemeinen Struktur 11 lassen sich aus dem Lithium-Salz des (Dimethylamino)acetaldehyd-dimethylhydrazons durch Alkylierung sowie durch Addition von Grignard-Verbindungen an das Ammoniumsalz 15 oder das N,O-Acetal 17 darstellen. Die Verbindungen 11 enthalten eine leicht eliminierbare Dimethylaminogruppe und gehen mit Säurechloriden oder nach Methylierung thermisch in Hydrazone 27 α,β-ungesättigter Aldehyde über. In den Salzen 26a, g läßt sich die Trimethylammoniumgruppe durch verschiedene Nucleophile verdrängen (→ 34-39).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190802
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    Intramolekulare Wechselwirkungen in Radikalkationen von Di- und Tetra(α-methoxy)-9,10-dihydro-9,10-ethanoanthracenen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2414-2429 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Intramolecular Interactions in Radical Cations of Di- and Tetra(α-methoxy)-9,10-dihydro-9,10-ethanoanthracenes[4 + 2]-Cycloaddition of maleic anhydride, 2-chloropropenoyl chloride and (E)-dichloroethene to 1,4-di- (3a) and 1,4,5,8-tetramethoxyanthracene (3b) yields the dihydroethanoanthracenes 4, 5, and 8, respectively. The predominant maleic anhydride adduct 4a is assigned the exo-configuration on the basis of the ESR spectrum of the radical cations 4a+·. The cycloadducts 5 and 8 are converted to the dihydroethanoanthracenes 10 via the ketones 6 or the dihydroethenoanthracenes 9, respectively. Aluminium chloride in nitromethane oxidizes the α-methoxydihydroethanoanthracenes 4, 6a, 8, and 10 to radical cations the ESR spectra of which are analyzed. Besides the expected proton hyperfine splittings of the 1,4-dimethoxybenzene moiety, one observes long-range transfer of spin density to the unsubstituted benzene ring [a(4H) = 0.008-0.010 mT] as well as to the syn-[10a+·: a(2H) = 0.013 mT] and anti-protons [a(2H) = 0.059-0.069 mT] of the ethano bridge. Of the radical cations possessing two 1,4-dimethoxybenzene rings, 4b and 10b do not exhibit dynamic ESR spectroscopic phenomena. On the other hand, the unpaired electron is exchanged rapidly (with respect to the hyperfine splitting time scala) between the 1,4-dimethoxybenzene rings of the radical cation 8b+·. The dependence of the exchange frequency on the temperature and the aluminium chloride concentration is indicative of ion-pair effects.
    Notes: Durch [4 + 2]-Cycloaddition von Maleinsäureanhydrid, 2-Chlorpropenoylchlorid bzw. (E)-Dichlorethen an 1,4-Di- (3a) und 1,4,5,8-Tetramethoxyanthracen (3b) entstehen die Dihydroethanoanthracene 4, 5 bzw. 8. Dem überwiegenden der Maleinsäureanhydrid-Addukte 4a wird aufgrund des ESR-Spektrums der Radikalkationen 4a+· die exo-Konfiguration zugeordnet. Die Cycloaddukte 5 und 8 werden über die Ketone 6 bzw. Dihydroethenoanthracene 9 in die Dihydroethanoanthracene 10 übergeführt. Aluminiumchlorid in Nitromethan oxidiert die α-Methoxydihydroethanoanthracene 4, 6a, 8 und 10 zu Radikalkationen, deren ESR-Spektren analysiert werden. Neben den erwarteten Protonen-Hyperfeinaufspaltungen des 1,4-Dimethoxybenzolrings beobachtet man weitreichenden Transfer von Spindichte zum unsubstituierten Benzolring [a(4H) = 0.008-0.010 mT] sowie zu den syn-[10a+·: a(2H) = 0.013 mT] und anti-Protonen [a(2H) = 0.059-0.069 mT] der Ethanobrücke. Von den Radikalkationen mit zwei 1,4-Dimethoxybenzolringen zeigen die aus 4b und 10b erhaltenen keine dynamischen ESR-spektroskopischen Phänomene. Dagegen wird in 8b+· das ungepaarte Elektron rasch bezüglich der Hyperfeinaufspaltungs-Zeitskala zwischen den 1,4-Dimethoxybenzolringen ausgetauscht. Die Abhängigkeit der Austauschfrequenz von der Temperatur und der Aluminiumchlorid-Konzentration weist auf Ionenpaar-Effekte hin.
    Additional Material: 4 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19861190803
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  • 166
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    Synthesen, Struktur und Eigenschaften von N-(Alkoxymethylen)carbamidsäureestern (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2444-2457 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses, Structures, and Properties of N-(Alkoxymethylene)carbamatesN-(Alkoxymethylene)carbamates 1 are synthesized from the imidate hydrochlorides 7 or from the imidates 8 and formates 9 in the presence of amine bases in mostly satisfactory yields (two optimized procedures, 10 examples).—An X-ray analysis of the derivative 1dbc shows an almost planar EtO—RC=N—C skeleton with an exo-s-cis-ethoxy function; the carboxylic group is nearly perpendicular to that plane.  - Quantum mechanical ab initio optimizations (3-21 G//3-21 G) were performed for nine conformations of the model substances 11; the calculated rotational barrier around the amide type bond is estimated to be ca. 5 kcal/mol. The ground state energy of the conformers of 11 is ca. 20 kcal/mol higher than that of the model for 10, N-formylcarbamic acid (12). —IR, 1H, and 13C NMR data for solutions of 1 are discussed.
    Notes: N-(Alkoxymethylen)carbamidsäureester 1 können durch Umsetzung der Imidsäureester-hydrochloride 7 oder der Imidsäureester 8 mit Chlorameisensäureestern 9 in Gegenwart von Aminbasen in meist guten bis sehr guten Ausbeuten hergestellt werden (zwei optimierte Syntheseverfahren, 10 Beispiele). Schonende Hydrolyse der Verbindungen 1 ergibt die N-Acylcarbamidsäureester 10.  - Die Röntgenstrukturanalyse des Derivates 1dbc zeigt ein planares RO—RC=N—C-Molekülgerüst mit exo-ständiger s-cis-orientierter Ethoxygruppe; die Carboxylgruppe steht annähernd senkrecht auf dieser Ebene.  - Mit Hilfe quantenmechanischer ab-initio-Berechnungen (3-21G//3-21 G) wurden Strukturen und Energien der Modellverbindungen 11 bestimmt und deren Rotationsbarriere um die amidische -Bindung abgeschätzt (ca. 5 kcal/mol). Im Vergleich mit N-Formylcarbamidsäure (12) (Modell für 10) besitzen die Verbindungen 11 eine um ca. 20 kcal/mol höhere Grundzustandsenergie. —IR-, 1H- und 13C-NMR-Daten von Lösungen von 1 werden diskutiert.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190805
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  • 167
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    Relative Reaktivität Alkyl-substituierter Alkene und Cycloalkene gegenüber Diarylcarbenium-Ionen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2473-2496 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Relative Reactivities of Alkyl-Substituted Alkenes and Cycloalkenes towards Diarylcarbenium IonsThe relative reactivities of alkyl-substituted alkenes 4 towards diarylmethyl cations 2 generated in situ from diarylmethyl chlorides 1 and Lewis acids were determined by competition experiments. The relative reactivities were almost independent of the nature of the Lewis acid. Eventual differences of the solvation free enthalpies of various activated complexes are, therefore, independent of the nature of the gegen ions. The rate acceleration by methyl groups - 6-50 by CH3 at the attacked vinylic position and approximately 104 at the developing carbenium centre - indicates a scarcely bridged transition state.
    Notes: Nach der Konkurrenzmethode wurden die relativen Reaktivitäten Alkyl-substituierter Alkene 4 gegenüber Diarylmethyl-Kationen 2 bestimmt, die in Gegenwart von Alken-Gemischen aus Diarylmethylchloriden 1 und Lewis-Säuren erzeugt wurden. Die Konkurrenz-konstanten werden durch die Art der Lewis-Säure nur wenig beeinflußt, so daß eine eventuelle Differenz der freien Solvatationsenthalpie verschiedener aktivierter Komplexe von der Natur des Gegenions unabhängig sein muß. Aus der 6-50fachen Reaktionsbeschleunigung durch Methylgruppen, die sich am angegriffenen Alken-Kohlenstoff befinden und der 104fachen Reaktivitätssteigerung durch Methylgruppen am neuen Carbeniumzentrum wird auf einen wenig verbrückten Übergangszustand geschlossen.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190808
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  • 168
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    Synthese von 2,5-Diazido-3,6-dicyan- und 2,6-Diazido-3,5-dicyan-1,4-benzochinon zur Darstellung von Dicyanketen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 844-849 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses of 2,5-Diazido-3,6-dicyano- and 2,6-Diazido-3,5-dicyano-1,4-benzoquinone for the Preparation of DicyanoketeneTwo short syntheses of 2,5-diazido-3,6-dicyano- (1) and 2,6-diazido-3,5-dicyano-1,4-benzo-quinone (3) as starting materials for the preparation of dicyanoketene in situ are reported; beyond that the compounds 14, 15, and 16a, b are synthesized.
    Notes: Es wird über zwei wenigstufige Synthesen von 2,5-Diazido-3,6-dicyan- (1) und 2,6-Diazido-3,5-dicyan-1,4-benzochinon (3) als Ausgangssubstanzen zur Darstellung von Dicyanketen in situ berichtet; darüber hinaus werden die Verbindungen 14, 15 und 16a, b dargestellt.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190308
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  • 169
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    Ester der Ferrocendithiocarbonsäure (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 850-856 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Esters of Ferrocenedithiocarboxylic AcidTwo methods were used to prepare esters of ferrocenedithiocarboxylic acid: 1. Alkylation of the ferrocenedithiocarboxylate anion in the piperidinium salt [C5H10NH2]+[Fc—CS2]- (1) by CH3I, C2H5I, and ethylene oxide gave mononuclear esters Fc—C(S)SR (R = CH3 (2), C2H5 (3), CH2CH2OH (4)), whereas the dinuclear methylene diester [Fc—C(S)S]2CH2 (9a) was formed using either CH2Cl2 or CH2I2. 2. The reaction of ferrocenecarbonyl chloride, Fc—C(O)Cl, with methanethiol, CH3SH, to give Fc—C(O)SCH3 (7) and subsequent sulfuration by P4S10 furnished Fc—C(S)SCH3 (2). The analogous reactions with dithiols, HS[CH2]nSH (n = 2 - 4), led to the dinuclear compounds [Fc—C(S)S]2[CH2]n (n = 2 (9b), 3 (9c), 4 (9d)). All the intermediates of the composition Fc—C(O)S[CH2]nSH (11b - d), [Fc—C(O)S]2[CH2]n (12b - d), and Fc—C(S)S[CH2]nSC(O) - Fc (13b - d) could be isolated. The new compounds were characterized on the basis of their 1H and 13C NMR spectra.
    Notes: Zwei Methoden wurden zur Darstellung von Estern der Ferrocendithiocarbonsäure angewandt: 1. Die Alkylierung des Ferrocendithiocarboxylat-Anions im Piperidinium-Salz [C5H10NH2]+ [Fc—CS2]- (1) mit CH3I, C2H5I und Ethylenoxid ergab einkernige Ester, Fc—C(S)SR (R = CH3 (2), C2H5 (3), CH2CH2OH (4)), während mit CH2Cl2 oder CH2I2 der zweikernige Methylendiester [Fc—C(S)S]2CH2 (9a) entstand. 2. Die Umsetzung von Ferrocencarbonsäurechlorid, Fc—C(O)Cl, mit Methanthiol, CH3SH, zu Fc—C(O)SCH3 (7) und anschließende Sulfurierung mit P4S10 lieferte Fc—C(S)SCH3 (2). Die analoge Reaktion mit Dithiolen HS[CH2]nSH (n = 2 - 4) führte zu den Zweikernverbindungen [Fc—C(S)S]2[CH2]n (n = 2 (9b), 3 (9c), 4 (9d)); alle Zwischenstufen der Zusammensetzung Fc—C(O)S[CH2]nSH (11b - d), [Fc—C(O)S]2[CH2]n (12b - d) und Fc—C(S)S-[CH2]nSC(O) - Fc (13b - d) konnten isoliert werden. Die neuen Verbindungen wurden anhand der 1H- und 13C-NMR-Spektren charakterisiert.
    Additional Material: 2 Tab.
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    URL: http://dx.doi.org/10.1002/cber.19861190309
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    Synthese und Eigenschaften von substituierten 1-Alkoxy-2-azaallenium-Salzen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 857-871 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Properties of Substituted 1-Alkoxy-2-azaallenium Salts12 novel substituted 1-alkoxy-2-azaallenium salts 1 have been prepared by reaction of the N-methyleneamides 3 with trialkyloxonium salts 4. During the alkylation reaction of the N-benzylideneamides 3m, n a formal disproportionation takes place to yield higher and lower oxidized 2-azaallenium salts (13, 14 from 3n) as the major products. The salts 1n, r, which are therefore not easily accessible by the alkylation route, can be prepared successfully by an acylation cleavage reaction of the N-(alkoxymethyl)imidates 8. The protonation of the substances 3 takes place exclusively at the nitrogen atom to give the N-acyliminium salts 19. Detailed spectroscopic data (IR, 1H, 13C NMR, MS) are included.
    Notes: Durch Umsetzung der N-Methylencarbonsäureamide 3 mit den Trialkyloxonium-Salzen 4 wurden 12 bislang nicht beschriebene substituierte 1-Alkoxy-2-azaallenium-Salze 1 hergestellt. Bei der Alkylierung der N-Benzylidencarbonsäureamide 3m, n tritt eine formale Disproportionierung zu höher und niedriger oxidierten 2-Azaallenium-Salzen (13, 14 bei 3n) als Hauptreaktion ein, deren Mechanismus untersucht wurde. Die durch Alkylierung nur schlecht zugänglichen Salze 1n, r können besser durch eine Acylspaltung von N-(Alkoxy-methyl)imidsäureestern 8 hergestellt werden. Die Protonierung der Verbindungen 3 erfolgt am Stickstoffatom unter Bildung der N-Acyliminium-Salze 19. Ausführliche spektroskopische Daten (IR, 1H- und 13C-NMR, MS) werden mitgeteilt.
    Additional Material: 1 Tab.
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    URL: http://dx.doi.org/10.1002/cber.19861190310
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    Sieben- (N2O2Si3) und achtgliedrige (N2O2Si4) Ringe aus einem (Hydroxysilyl)hydrazin und 1-Amino-3-fluorsiloxanen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 872-877 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Seven- (N2O2Si3) and Eight-membered (N2O2Si4) Rings from a (Hydroxysilyl)hydrazine and 1-Amino-3-fluorosiloxanesHalogeno-functional siloxanes [(Me3C)2SiCl—O—SiHalR2, Hal = F, R = CMe3 (2), Hal = Cl, R = Ph (3)] are obtained in the reaction of dihalogenosilanes with (Me3C)2Si(Cl)OLi (1a). (Me3C)2Si(Cl)OH reacts smoothly with ammonia to form the aminosilanol (Me3C)2Si(NH2)OH (4). With fluorosilanes its lithium salt 4a yields the amino- and fluoro-functional siloxanes 5 - 8 [(Me3C)2Si(NH2) —O—SiFRR′, R = R′ = Me (5), R = R′ = CMe3 (6), R = F, R′ = CMe3 (7), R = F, R′ = N(SiMe3)2 (8)]. Primary amines react with 1 by intermolecular HCl elimination to give the 1-chloro-3-hydroxysiloxane 9, hydrazine reacts to form the N,N′-bis(hydroxysilyl)hydrazine 10, methylhydrazine to yield the N-(hydroxysilyl)-N-methylhydrazine 11, and N,N′-dimethylhydrazine to give 9. The reaction of the dilithium salt 10a with F3SiN(SiMe3)2 leads to the formation of the seven-membered N2O2Si3 ring 12. The 1,5,3,7,2,4,6,8-dioxadiazatetrasilocanes 13 and 14 are obtained by LiF elimination from lithiated 5 and 7, respectively.
    Notes: Halogenfunktionelle Siloxane [(Me3C)2SiCl - O—SiHalR2, Hal = F, R = CMe3 (2), Hal = Cl, R = Ph (3)] werden durch Reaktion der Dihalogensilane mit (Me3C)2Si(Cl)OLi (1a) erhalten. Mit Ammoniak reagiert (Me3C)2Si(Cl)OH (1) glatt unter Bildung des Aminosilanols (Me3C)2Si(NH2)OH (4), dessen Lithiumsalz 4a mit Fluorsilanen die amino- und fluorfunktionellen Siloxane 5 - 8 [(Me3C)2Si(NH2) - O—SiFRR′, R = R′ = Me (5), R = R′ = CMe3 (6), R = F, R′ = CMe3 (7), R = F, R′ = N(SiMe3)2 (8)] bildet. Primäre Amine reagieren mit 1 unter intermolekularer HCl-Abspaltung zum 1-Chlor-3-hydroxysiloxan 9, Hydrazin zum N,N′-Bis(hydroxysilyl)hydrazin 10, Methylhydrazin zum N-(Hydroxysilyl)-N′-methyl-hydrazin 11 und N,N′-Dimethylhydrazin zu 9. Die Reaktion des Dilithiumsalzes 10a mit F3SiN(SiMe3)2 führt zur Bildung des siebengliedrigen N2O2Si3-Ringes 12. Durch LiF-Eliminierung aus lithiiertem 5 und 7 entstehen die 1,5,3,7,2,4,6,8-Dioxadiazatetrasilocane 13 und 14.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190311
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    Chemie der Übergangsmetall-Heterocyclen-Komplexe, II. Synthese und Elektrochemie von Carbonylchrom-Komplexen der Bithiophen-Reihe (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 878-886 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Chemistry of Transition Metal Heterocyclic Complexes, II. Synthesis and Electrochemistry of Carbonyl Chromium Complexes in the Bithiophen SeriesThe (substituted) (bithiophene)tricarbonylchromium complexes 4a - g are formed in yields up to 95% upon treatment of tricarbonyltris(γ-picoline)chromium with 2,2′-bithiophene (1a) and its derivatives 1b - e and 1g, respectively, in the presence of the Lewis acid BF3. The oxidation of the new compounds, as investigated by means of cyclovoltammetry, is irreversible and effects decomposition of the complexes.
    Notes: Durch Umsetzung von Tricarbonyltris(γ-picolin)chrom (3) mit 2,2′-Bithiophen (1a) und seinen Derivaten 1b - e und 1g bilden sich in Gegenwart der Lewis-Säure BF3 die (substituierten) Bithiophen-Chromtricarbonyl-Komplexe 4a - g in Ausbeuten bis 95%. Die cyclovoltametrisch untersuchte Oxidation der neuen Verbindungen verläuft irreversibel unter Zerfall der Komplexe.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19861190312
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    Oxidative aminomercuration of 2-propyn-1-ols. Stereoselective syntheses and structures of cis-[1,4]oxazino[3,2-b]-1,4-oxazine derivatives (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 887-899 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Oxidative Aminomercurierung von 2-Propin-1-olen. Stereoselektive Synthese und Struktur von cis-[1,4]Oxazino[3,2-b]-1,4-oxazin-DerivatenDie Reaktion von 2-Propin-1-olen 1 mit 2-Aminoalkoholen 7 in Gegenwart von Quecksilber(II)-chlorid beginnt mit einer oxidativen Aminomercurierung, gefolgt von hoch stereo-selektiven Reaktionsschritten, die zu cis-[1,4]Oxazino[3,2-b]-1,4-oxazin-Derivaten 10 führen. Nach den Röntgenstrukturanalysen von 10c,f,g zeigen diese Verbindungen die gleiche Anordnung um die zentrale Bindung, und zwar so, daß die anomere Stabilisierung ein Maximum erreicht.
    Notes: The reactions of 2-Propin-1-ols 1 with 2-amino alcohols 7 and mercury(II) chloride start with an oxidative aminomercuration step followed by a series of highly stereoselective processes leading to cis-[1,4]oxazino[3,2-b]-1,4-oxazine derivatives 10. X-Ray analyses of 10c,f,g show that these compounds have the same geometrical arrangement around their central fusion bond in such a way that anomeric stabilisation reaches a maximum.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190313
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    Decabenzylgermanocen, -stannocen und -plumbocen. Synthese und Struktur von luftstabilen Metallocenen der 4. Hauptgruppe des Periodensystems der Elemente (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2656-2667 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Decabenzylgermanocene, -stannocene and -plumbocene. Synthesis and Structure of Air-stable Metallocenes of Main Group IVGermanium diiodide, tin dichloride, or lead diacetate reacts with pentabenzylcyclopentadienyllithium (1) to give decabenzylgermanocene (2), decabenzylstannocene (3) or decabenzylplumbocene (4), respectively. The air-stable metallocenes were characterized by IR, Raman, NMR, tin-119m-Mössbauer (3), and mass spectroscopy. The X-ray structural analysis shows for all three compounds an angle of 31 to 36° between the planes of the two cyclopentadienyl rings and a shielding of the lone pair of electrons at the metal atom by three of the ten benzyl groups each.
    Notes: Germaniumdiiodid, Zinndichlorid bzw. Bleidiacetat reagiert mit Pentabenzylcyclopentadienyllithium (1) unter Bildung von Decabenzylgermanocen (2), Decabenzylstannocen (3) bzw. Decabenzylplumbocen (4). Die luftstabilen Metallocene wurden durch IR-, Raman-, NMR-, 119mSn-Mößbauer- (3) und Massenspektren charakterisiert. Die Röntgenstrukturanalyse der Verbindungen zeigt, daß die Ebenen der beiden Cyclopentadienylringe einen Winkel zwischen 31 und 36° einschließen, und daß eine Abschirmung des freien Elektronenpaares am Metallatom jeweils durch drei der zehn Benzylgruppen erfolgt.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190822
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    Asymmetrische reduktive Aminierung von Cycloalkanonen, 5. Synthese und absolute Konfiguration 2-substituierter Cyclopentanamine (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2668-2677 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Asymmetric Reductive Amination of Cycloalkanones, 5. Synthesis and Absolute Configuration of 2-Substituted CyclopentanaminesIn an asymmetric synthesis 2-substituted cyclopentanamines are obtained from racemic cyclopentanones by means of reductive amination in a three-step procedure. Condensation of the ketones 3(n) with optically active 1-phenylethylamines yields imine mixtures 4(n), which are hydrogenated with Raney nickel to give the optically active, diastereomerically pure secondary amines 5(n). Hydrogenolysis with Palladium-on-charcoal leads to high grade enantiomerically pure primary amines 6(n) with good yields. The relative configuration of the amines 5(n) and 6(n) is elucidated by 1H and 13C NMR techniques. The absolute configuration is determined by X-ray analysis of the 4-bromobenzamide 8 of the primary amine (+)-6(n)e and with the help of CD of the salicylidenes 9(n). The kinetically controlled asymmetric hydrogenation with a first order transformation as proved reaction mechanism in the cyclohexanamine line is confirmed for this investigation. The hydrogenation runs like-induced to the cis-configurated amines 5(n) and 6(n), respectively.
    Additional Material: 5 Tab.
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    URL: http://dx.doi.org/10.1002/cber.19861190823
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    Electron transfer reactions. Reaction of furanones and bifurandiones with potassium and oxygen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 917-928 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Elektronen-Übertragungs-Reaktionen. Reaktion von Furanonen und Bifurandionen mit Kalium und SauerstoffBei der Behandlung von Furanonen (1a - c, 25, 34) und Bifurandionen (23, 37) mit Kalium in THF entstehen Radikalanion-Zwischenstufen, die mit Sauerstoff zu Superoxid reagieren, das seinerseits mit den Ausgangsfuranonen und -bifuranonen weiterreagiert. So ergab die Reaktion von 1a mit Kalium eine Mischung von 4-Oxo-2,2,4-triphenylbutansäure (7a), 1,3,3-Triphenyl-2-propen-1-on (11a) und Benzoesäure (12). Unter ähnlichen Bedingungen reagierte 11a selbst zu einer Mischung von Benzophenon (18a) und 12. Ähnliche Ergebnisse wurden im Falle von 1b und c erhalten. Das Bifurandion 23 ergab mit Kalium eine Mischung von 2(5H)-Furanon 25, 2,3-Diphenylpropensäure (31) und 12. 25 selbst reagierte mit Kalium unter ähnlichen Bedingungen zur selben Mischung von 31 und 12. 3-Phenyl-2(3H)-benzofuranon (34) führte mit Kalium jedoch zu keinem isolierbaren Produkt; nur Ausgangsmaterial wurde zurückgewonnen. Unter vergleichbaren Bedingungen lieferte das Bifurandion 37 das Fragmentierungsprodukt 34. Mit Hilfe der cyclischen Voltammetrie wurden die zu den Radikalanionen führenden Reduktionspotentiale gemessen. Die Radikalanion-Zwischenstufen wurden durch ihre Elektronenspektren charakterisiert.
    Notes: Treatment of furanones (1a - c, 25, 34) and bifurandiones (23, 37) with potassium in THF gave rise to radical anion intermediates, which reacted with oxygen to give superoxide and ultimately products derived through the reaction of superoxide with the starting furanones and bifurandiones. Thus, the reaction of 1a with potassium gave a mixture of 4-oxo-2,2,4-triphenylbutanoic acid (7a), 1,3,3-triphenyl-2-propen-1-one (11a), and benzoic acid (12). The reaction of 11a itself, under similar conditions, gave a mixture of benzophenone (18a) and 12. Similar reactions have been observed in the case of 1b and c. The bifurandione 23, on treatment with potassium, gave a mixture of the 2(5H)-furanone 25, 2,3-diphenylpropenoic acid (31), and 12. The reaction of 25 itself with potassium under similar conditions gave the same mixture of 31 and 12. Treatment of 3-phenyl-2(3H)-benzofuranone (34) with potassium, however, did not give any isolable product; only the starting material could be recovered. Under similar conditions, the bifurandione 37 gave the fragmentation product 34. Cyclic voltammetric studies have been employed to measure the reduction potentials, leading to radical anions, and these intermediates have been characterized through their electronic spectra.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19861190315
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    Reactions of uracils, 7. Synthesis and novel consecutive thermal [1,5]-sigmatropic rearrangements of 6-(alkylamino)-5-ethenyluracils (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 943-949 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reaktionen von Uracilen, 7. Synthese und eine neue Sequenz thermischer [1,5]-sigmatroper Umlagerungen von 6-(Alkylamino)-5-ethenyluracilenNeue 6-(Alkylamino)-5-ethenyluracile (2d und 7) werden dargestellt, um Substituenteneffekte bei thermischen Reaktionen zu untersuchen. Ähnlich 2a werden 2d und 7 beim Erhitzen in Dowtherm® A und nach anschließender Verseifung in die 6-Amino-5-(ethoxycarbonyl[phenyl]ethyl)uracile 4 bzw. 8 übergeführt. Erhitzen in Xylol liefert die intermediären Imine 11 und 12. Deuterierungsexperimente belegen aufeinanderfolgende thermische [1,5]-H-Wanderungen (2a-D1 → 4-D1 und 4-D2; 2a′-D2 → 4′-D1). Die Mechanismen werden diskutiert.
    Notes: Additional 6-(alkylamino)-5-ethenyluracils (2d, 7) have been prepared for investigating substituent effects in thermal reactions. Like 2a, upon heating in Dowtherm® A 2d and 7 afford after saponification 6-amino-5-(ethoxycarbonyl[phenyl]ethyl)uracils 4 and 8, respectively. After refluxing in xylene the intermediary imines 11 and 12 can be isolated. Deuteration experiments reveal consecutive thermal [1,5]H-migrations (2a - D1 → 4-D1, and 4-D2; 2a′-D2 → 4′-D1). The mechanism is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190317
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  • 178
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    1-Methylbenzvalen - Synthese und einige Reaktionen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 960-970 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 1-Methylbenzvalene - Synthesis and Several Reactions1-Methylbenzvalene (1) has been obtained in preparatively useful quantities from the reaction of cyclopentadienyllithium with 1,1-dichloroethane and n-butyllithium. Hydrogenation of 1 by means of diimine afforded 1-methyltricyclo[3.1.0.02,6]hexane (3). Addition of benzonitrile oxide and 2,4,6-trimethylbenzonitrile oxide to the double bond of 1 gave rise to the formation of a mixture of the isomeric Δ2-isoxazoline derivatives 4 and 5. 4-Methyl-4H-1,2,4-triazole-3,5-dione and 1 reacted to give the rearranged adducts 6 - 8. At temperatures as low as 20°C 8 transformed slowly into the dihydrodiazasemibullvalene derivative 9. Using [6-D]-1-methylbenzvalene (1a) the mechanisms of the reactions leading to 6 - 9 have been studied.
    Notes: Aus der Reaktion von Cyclopentadienyllithium mit 1,1-Dichlorethan und n-Butyllithium ging in präparativ brauchbaren Mengen 1-Methylbenzvalen (1) hervor. Seine Hydrierung mit Diimin erbrachte 1-Methyltricyclo[3.1.0.02,6]hexan (3). Benzonitriloxid und 2,4,6-Trimethylbenzonitriloxid addierten sich an die Doppelbindung von 1 unter Bildung von Gemischen der isomeren Δ2-Isoxazolin-Derivate 4 und 5. 4-Methyl-4H-1,2,4-triazol-3,5-dion ergab mit 1 die umgelagerten Addukte 6 - 8. Schon bei 20°C wandelte sich 8 langsam in das Dihydrodiazasemibullvalen-Derivat 9 um. Durch Einsatz von [6-D]-1-Methylbenzvalen (1a) wurden die Mechanismen der zu 6 - 9 führenden Reaktionen untersucht.
    Additional Material: 1 Tab.
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    URL: http://dx.doi.org/10.1002/cber.19861190319
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  • 179
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    Additionen von Benzvalen an Nitriloxide. Eine Synthese für Benzvalen-3-carbonitril (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 950-959 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Additions of Benzvalene to Nitrile Oxides. A Synthesis for Benzvalene-3-carbonitrile2,4,6-Trimethylbenzonitrile oxide, benzonitrile oxide, and fulminic acid undergo cycloaddition to benzvalene (1) to give the Δ2-isoxazolines 2a - c in high yields. By means of competition experiments the ratio of the rate constants for the reactions of 1 and norbornene with benzonitrile oxide has been determined to be kbenzvalene/knorbornene ≈ 1. The adduct 2c of fulminic acid was transformed to benzvalene-3-carbonitrile (4) by the following simple sequence: ring opening by sodium methoxide to yield the β-hydroxycarbonitrile 3, tosylation of 3, and, finally, elimination of toluenesulfonic acid with potassium tert-butoxide. - From the X-ray structure analysis of 2b the dihedral angle and the length of the central bond of the bicyclo[1.1.0]butane moiety have been determined to be 111.8° and 1.464 Å, respectively.
    Notes: 2,4,6-Trimethylbenzonitriloxid, Benzonitriloxid und Knallsäure ergaben mit Benzvalen (1) in hohen Ausbeuten die Δ2-Isoxazoline 2a - c. Durch Konkurrenzexperimente wurde das Verhältnis der Geschwindigkeitskonstanten der Additionen von Benzonitriloxid an 1 und Norbornen kBenzvalen/kNorbornen ≈ 1 bestimmt. Das Knallsäure-Addukt 2c ließ sich in der folgenden einfachen Reaktionssequenz in Benzvalen-3-carbonitril (4) umwandeln: Ringöffnung durch Natrium-methoxid zum β-Hydroxynitril 3, dessen Tosylierung und schließlich Eliminierung von Toluol-sulfonsäure mit Kalium-tert-butoxid. - Mit Hilfe der Röntgenstrukturanalyse wurden für das Bicyclo[1.1.0]butan-Gerüst von 2b der Interplanarwinkel zu 111.8° und die Länge der Zentral-bindung zu 1.464 Å ermittelt.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190318
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    Reaktive π-Übergangsmetallkomplexe der 8. Nebengruppe, I. (η6-Aren)(η5-2,5-dihydro-1,2,5-thiadiborol)eisen: Synthesen aus Bis(aren)eisen und Aren-bis(ethen)eisen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 971-979 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactive π-Complexes of the Group VIII Transition Metals, I. (η6-Arene)(η5-2,5-dihydro-1,2,5-thiadiborol)iron: Syntheses from Bis(arene)iron and Arene-bis(ethene)ironBis(arene)iron 1a - e, (arene = p-xylene, benzene, benzotrifluoride, 1,4-difluorobenzene) react in the temperature range of -100 to -60°C with 3,4-diethyl-2,5-dihydro-2,5-dimethyl-1,2,5-thiadiborole (thiadiborolene, 2) to form reactive intermediates which decompose at -30°C and (η6-arene)(η5-thiadiborolene)iron 3a - e are obtained. Alternatively, the synthesis is achieved via arene-bis(ethene)iron 4a,c (arene = p-xylene, benzene), which is formed from 1a,c and ethene at low temperature. Reactions, spectroscopic data, and the crystal structure of (η6-benzene)(η5-thiadiborolene)iron (3c) are reported.
    Notes: Bis(aren)eisen 1a - e (Aren = p-Xylol, Toluol, Benzol, Benzotrifluorid, 1,4-Difluorbenzol) reagieren im Temperaturbereich von - 100 bis -60°C mit 3,4-Diethyl-2,5-dihydro-2,5-di-methyl-1,2,5-thiadiborol (Thiadiborolen, 2) zu reaktiven Zwischenverbindungen, die durch Zersetzung bei -30°C (η6-Aren)(η5-thiadiborolen)eisen 3a - e ergeben. Alternativ gelingt die Synthese über Aren-bis(ethen)eisen 4a, c (Aren = p-Xylol, Benzol), welche bei tiefen Temperaturen aus 1a, c und Ethen darstellbar sind. Reaktionen, spektroskopische Daten und die Kristallstruktur von (η6-Benzol)(η5-thiadiborolen)eisen (3c) werden mitgeteilt.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190320
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    Darstellung, ESR- und ENDOR-Untersuchung von Radikalkationen des Tetraphenylhydrazins, des 5,6-Dihydro-5,6-diphenylbenzo[c]cinnolins und des Benzo[c]benzo[3,4]cinnolino[1,2-a]cinnolins (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 980-990 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Generation, ESR and ENDOR Study of Radical Cations Derived from Tetraphenylhydrazine, 5,6-Dihydro-5,6-diphenylbenzo[c]cinnoline, and Benzo[c]benzo[3,4]cinnolino[1,2-a]cinnolineRadical cations of the title compounds (1a·+, 2·+, 3·+) and of a series of derivatives (1b·+, 1ċ+, 6a·+ - ċ+) representing hydrazine radical cations were generated by oxidation. ENDOR studies of the tetraarylhydrazine radical cations 1a·+ - ċ+ confirm the hindered rotation of the aryl groups and yield a partial assignment of the hyperfine splitting constants. According to the ESR-ENDOR results of 1a·+ and 3·+ linkage of the N,N′-phenyl groups through their o-positions does not considerably flatten the conjugation system.
    Notes: Die Hydrazin-Radikalkationen der Titelverbindungen (1a·+, 2·+, 3·+) sowie einer Reihe von Derivaten (1b·+, 1c·+, 6a·+ - e·+) wurden durch Oxidation erzeugt. ENDOR-Untersuchungen der Tetraarylhydrazin-Radikalkationen 1a·+ - c·+ bestätigen die gehinderte Rotation der Arylreste und liefern eine partielle Zuordnung der HFS-Kopplungskonstanten. Nach den ESR- und ENDOR-Ergebnissen von 1a·+ und 3·+ führt die Verknüpfung der N,N′-Phenylreste über ihre o-Positionen zu keiner beträchtlichen Einebnung des Konjugationssystems.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190321
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    Über die Konfigurations- und Substituenten-Abhängigkeit der Pt — Cl-Valenzschwingungsfrequenzen und der 31P-NMR-Parameter in substituierten cis- und trans-Dichlorobis-(triphenylphosphan)platin(II)-Verbindungen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1694-1703 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the Configurational and Substituent Dependence of the Pt—Cl Stretching Frequencies and of the 31P NMR Parameters in Substituted cis- and trans- Dichlorobis(triphenylphosphane)platinum(II) CompoundsCorrelations between substituent constants σ, Pt — Cl vibrational frequencies and 31P NMR parameters 1J[195Pt,31P] und δ[31P] for compounds of the type cis- and trans-{Pt-[P(aryl)(aryl′)(aryl″)]2 Cl2} (aryl, aryl′, aryl″ = substituted phenyl rings) are reported and discussed with respect to bonding properties.
    Notes: Zusammenhänge zwischen Substituenten-Konstanten σ, Pt—Cl-Valenzschwingungsfrequenzen und 31P-NMR-Parameter 1J[195Pt, 31P] und δ[31P] für die Verbindungen des Typs cis- und trans-{Pt[P(aryl)(aryl′)(aryl″)]2 Cl2} (aryl, aryl′, aryl″ = substituierte Phenyl-Ringe) werden beschrieben und im Hinblick auf die Bindungseigenschaften diskutiert.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190521
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  • 183
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    Photochemie des 1,3-Distyrylbenzols  -  Ein neuer Weg zu syn-[2.2](1,3)Cyclophanen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1704-1715 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Photochemistry of 1,3-Distyrylbenzene  -  A New Route to syn-[2.2](1,3)CyclophanesDepending on the reaction conditions the irradiation of the title compound 1 leads to cyclodimerization 1 → 6, dehydrogenating cyclization 1 → 11, 12 or a combination of both processes 1 → 13, 14, 15. The stereoisomeric [2.2](1,3)cyclophanes 6a - c as well as the access into the pyrene series 15, 16, 18 are of special synthetic interest.
    Notes: In Abhängigkeit von den Reaktionsbedingungen beobachtet man bei der Photolyse der Titelverbindung 1 Cyclodimerisierung 1 → 6, dehydrierende Cyclisierung 1 → 11, 12 oder eine Kombination von beiden 1 → 13, 14, 15. Von besonderem synthetischem Interesse sind dabei die stereoisomeren [2.2](1,3)Cyclophane 6a - c und der Zugang in die Pyrenreihe 15, 16, 18.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190522
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    Reaction of trialkyl orthoformates with the aluminium derivatives of some α-unsaturated bromides. Preparation of β-unsaturated acetals (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1725-1730 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reaktion von Trialkylorthoformaten mit den Aluminium-Derivaten einiger α-ungesättigter Bromide. Darstellung von β-ungesättigten AcetalenDie Aluminium-Derivate 2, 4 und 7 α-ungesättigter Bromide, dargestellt in Ether, sind sehr reaktionsfähig gegenüber Trialkylorthoformaten. Mit Hilfe dieser Reaktion, durchgeführt bei -80°C, können auf einfache Weise β-ungesättigte Acetale 3, 5 bzw. 8 dargestellt werden.
    Additional Material: 2 Tab.
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    URL: http://dx.doi.org/10.1002/cber.19861190524
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    Fluoreszenz-Untersuchungen an styrylsubstituierten Benzolen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1716-1724 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Investigations on the Fluorescence of Styryl-substituted BenzenesFluorescence decay measurements of the stilbene-like compounds 1 - 4 demonstrate that the average lifetimes of these molecules in the electronically excited singlet state are about 102 times higher than for trans-stilbene itself. According to UV absorption and excitation spectra this is due to a new S1 state, which corresponds to a forbidden S0 → S1 transition on the long-wavelength edge of the intense absorption.
    Notes: Die Fluoreszenz-Abklingzeiten der stilbenartigen Verbindungen 1 - 4 zeigen, daß die mittleren Lebensdauern dieser Moleküle im elektronisch angeregten Singulettzustand um rund zwei Zehnerpotenzen höher sind als bei trans-Stilben selbst. Anhand von UV-Absorptions-und Anregungsspektren wird das auf einen neu gefundenen S1-Zustand zurückgeführt, der einem verbotenen Übergang S0 → S1 auf der langwelligen Seite der intensiven Absorption entspricht.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190523
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  • 186
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    Enantioselektive katalytische Hydrierung von α-(Acetylamino)-zimtsäure mit einem Rhodium-Phosphankomplex in wäßriger Lösung (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1731-1733 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Enantioselective Catalytic Hydrogenation of α-(Acetylamino)cinnamic Acid with a Rhodium Phosphane Complex in Aqueous SolutionThe synthesis of [(3R,4R)-3,4-bis(diphenylphosphino)-1,1-dimethylpyrrolidinium-P,P′](1,5-cyclooctadiene)rhodium bis(tetrafluoroborate) (5) is described. With this water-soluble catalyst the sodium salt 6c of α-(Acetylamino)cinnamic acid (6a) is hydrogenated in aqueous solution to give (S)-N-acetylphenylalanine with 90% ee.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190525
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    McMurry-Reaktion der 2-Alkyl-3-ethoxyacroleine (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1734-1736 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: McMurry Reaction of 2-Alkyl-3-ethoxyacroleinsMcMurry reductive coupling of 2-alkyl-3-ethoxyacroleins 1 yields 2,5-dialkylhexadienedials 6. (E) Configuration at the 2,3- and 4,5-double bonds of these dialdehydes is derived from three-bond carbon-13 proton coupling. A mechanism similiar to that discussed for McMurry coupling of carbonyl compounds is proposed.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190526
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    Masthead (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986) 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190601
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    Oxopropenylierung von Alkylmagnesiumhalogeniden mit 3-(Trimethylsilyloxy)acroleinen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1737-1744 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Oxopropenylation of Alkylmagnesium Halides by 3-(Trimethylsilyloxy)acroleinsOxopropenylation of alkylmagnesium halides 4 by 3-(trimethylsilyloxy)acroleins 3 selectively yields the (E)-isomers of α,β-unsaturated aldehydes such as 4-phenyl-2-butenals 9, 3-cyclopropylpropenals 10, 3-cyclohexylpropenals 11, 3-(3-menthyl)propenals 12, and 2,5-hexadienals 13. 3-Hydroxyenolsilylethers 6 are isolated when allylmagnesium chloride is used as carbon nucleophile; to conclude, the reaction primarily involves nucleophilic addition of the Grignard reagent at the aldehyde carbon of the acrolein 3.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190527
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  • 190
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    Metallkomplexe mit verbrückten permethylierten Cyclopentadienylliganden (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1750-1754 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Metal Complexes with Bridged Permethylated Cyclopentadienyl LigandsThe preparation of the permethylated silyl-bridged dicyclopentadienyl ligands Me2Si(Me4C5H)2 (1) and C2H4(Me2Si(Me4C5H))2 (2) is reported. Reaction of dimetalated 1 with TiCl4 and ZrCl4 yielded the corresponding metallocenophane dihalides 3 and 4, while treatment of the dilithio derivative of 2 with GeCl2 · dioxane, SnCl2, and FeCl2 yielded the bridged metallocenes 5, 6, and 7.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190529
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  • 191
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    Synthese neuer 1λ6,2,6-Thiadiazine durch Kondensationsreaktion mit S,S-Dialkylschwefeldiimiden (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1745-1749 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis of New 1λ6,2,6-Thiadiazines by Condensation with S,S-Dialkylsulfur DiimidesReactions of ketene mercaptals 1a, b, d with S,S-dialkylsulfur diimides 2a - c lead to colourless 1λ6,2,6-thiadiazines 4a - i; reaction of 1c with 2a - c leads to ring-open products 3a - c. 5-Methyl-substituted 1λ6,2,6-thiadiazines 6a, c, d can be prepared by condensation of S,S-dialkylsulfur diimides 2a, c, d with acrylic acid derivative 5.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190528
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  • 192
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    Diazoverbindungen, 68. Dibenzo[a,c]cyclooctene und Dibenzo[a,c]heptafulvene aus 5-(Diazomethyl)-5H-dibenzo[a,c]cycloheptenen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1755-1765 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Diazo Compounds, 68. Dibenzo[a,c]cyclooctenes and Dibenzo[a,c]heptafulvenes from 5-(Diazomethyl)-5H-dibenzo[a,c]cycloheptenes5,6-Dichloro-5H-dibenzo[a,c]cycloheptene (11) reacts with the silver (diazomethyl)phosphoryl compounds 12a-d and the mercury bis(diazomethylcarbonyl) compounds 12e-h, respectively, by electrophilic diazoalkane substitution to yield the 5-(diazomethyl)-5H-dibenzo[a,c]cycloheptenes 14a-h. The copper(II) acetylacetonate-catalyzed decomposition of 14a, c, e and g in toluene leads to the formation of both dibenzo[a,c]cyclooctenes 16a-d and 17a, b by ring enlargement and of dibenzo[a,c]heptafulvenes 18a-d by 1,2-H-shift.
    Notes: 5,6-Dichlor-5H-dibenzo[a,c]cyclohepten (11) geht mit den Silber-(diazomethyl)phosphorylverbindungen 12a-d bzw. den Quecksilber-bis(diazomethylcarbonyl)verbindungen 12e-h elektrophile Diazoalkansubstitution zu den 5-(Diazomethyl)-5H-dibenzo[a,c]cycloheptenen 14a-h ein. Kupfer(II)-acetylacetonat-katalysierte Zersetzung von 14a,c,e und g in Toluol führt über Ringerweiterung zu den Dibenzo[a,c]cyclooctenen 16a-d und 17a,b sowie unter 1,2-H-Shift zu den Dibenzo[a,c]heptafulvenen 18a-d.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190602
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  • 193
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    Trimethylsilylcyanid als Umpolungsreagens, XI. Über den ambidenten Charakter substituierter Allyl-Anionen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1772-1800 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Trimethylsilyl Cyanide  -  A Reagent for Umpolung, XI. On the Ambident Character of Substituted Allylic AnionsThe dependence of the α/γ-ratio of alkylation products on several factors has been determined with 1-cyano-3-aryl-1-(trimethylsiloxy)allylic anions. Increasing amounts of γ-product are found in more polar solvents, with larger alkali ions, on addition of HMPT, with smaller alkyl groups in the electrophile, and especially with p-cyanophenyl groups. In contrast, temperature and leaving groups have minor effects. On substitution of the O-silyl group by O-methyl and O-ethoxycarbonyl, α-alkylation predominates strongly. The results are compared to known allylic anions. Furthermore, the isomerisation of compounds of type C to type B is described as well as a new addition reaction of cyanoformates to aldehydes.
    Notes: An 1-Cyan-3-aryl-1-(trimethylsiloxy)allyl-Anionen (6) wird das Verhältnis der α/γ-Alkylierung in Abhängigkeit von verschiedenen Faktoren bestimmt. Dabei wird der γ-Anteil durch stärker polare Solventien, größere Alkali-Ionen, Zusatz von HMPT, kleinere Alkylreste im Elektrophil und besonders p-Cyanphenylreste erhöht, während Abgangsgruppen des Elektrophils und die Temperatur wenig Einfluß ausüben. Ersatz der O-Silylgruppe durch die O-Methyl- und O-Ethoxycarbonylgruppe bewirkt α-Alkylierung. Die Ergebnisse werden im Vergleich mit literaturbekannten Allyl-Anionen diskutiert. Außerdem werden die Isomerisierung der Verbindungen vom Typ C zu Typ B sowie eine neue Additionsreaktion von Cyanameisensäureester an Aldehyde beschrieben.
    Additional Material: 13 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190604
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  • 194
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    Norpinene (Bicyclo[3.1.1]hept-2-ene) aus Homobenzvalenen (Tricyclo[4.1.0.02,7]hept-3-enen) (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 3027-3044 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Norpinenes (Bicyclo[3.1.1]hept-2-enes) from Homobenzvalenes (Tricyclo[4.1.0.02,7]hept-3-enes)4,5-Dibromo-(1b) and 4,5-dichlorohomobenzvalene (1c) were converted into the tetrahalonorpinenes 2b, c by elemental bromine. In the case of unsubstituted homobenzvalene (1a) the analogous reaction could be achieved in 1% yield only by pyridinium perbromide. Treatment of 1a, b as well as of chlorohomobenzvalenyl nitrobenzoate 1d with iodine furnished the diiodonorpinenes 3a-c. However, 7,7-dibromotetracyclo[4.1.0.02,4.03,5]heptane (4) and bromine gave the tetrabromo-trans-tricyclo[4.1.0.02,4]heptane derivative 5. - On irradiation in the presence of thiophenol, the homobenzvalenes 1a, c, e, f were transformed into the 6-(phenylthio)norpinenes 6a-d. The hydroxyhomobenzvalenes 1g, h afforded the 6-(phenylthio)norpinenes 6e, g as major products, the configuration at C-4 of which is inverted as compared to that of 6b-d. By using [D2]-1a it was shown that with respect to stereochemistry the addition of thiophenol does not proceed uniformly. Without irradiation, 1a was consumed by thiophenol rather slowly at 20°C with formation of the norcarene derivatives 9 and 10 in addition to 6a. - By treatment with LiAlH4 the dichloro compound 6b gave the monochloro derivative 6h. Both 6b and 6h, however the latter one with a better yield, were converted into unsubstituted norpinene (11a) by means of sodium in liquid ammonia, thus providing a new and preparatively useful synthesis for 11a. Analogously, 6c, d furnished 4-phenylnorpinene (11b). The reaction of norpinenes 3a and 11a with N-bromosuccinimide produced the allylbromides 3d and 11c, respectively. - The 13C NMR spectra of the 4-substituted norpinenes revealed a diagnostically important γ-anti-substituent effect.
    Notes: 4,5-Dibrom-(1b) und -Dichlorhomobenzvalen (1c) wurden durch elementares Brom in die Tetrahalogennorpinene 2b, c umgewandelt. Die analoge Reaktion konnte bei unsubstituiertem Homobenzvalen (1a) mit 1% Ausbeute nur durch Pyridiniumperbromid erzielt werden. Aus 1a, b sowie dem Chlorhomobenzvalenyl-nitrobenzoat 1d und Iod gingen die Diiodnorpinene 3a-c hervor. Dagegen erbrachte 7,7-Dibromtetracyclo[4.1.0.02,4.03,5]heptan (4) mit Brom das Tetrabrom-trans-tricyclo[4.1.0.02,4]heptan-Derivat 5. - Beim Belichten in Gegenwart von Thiophenol ergaben die Homobenzvalene 1a, c, e, f die 6-(Phenylthio)norpinene 6a-d. Die Hydroxyhomobenzvalene 1g, h lieferten überwiegend die 6-(Phenylthio)-norpinene 6e, g, deren Konfiguration an C-4 im Vergleich zu derjenigen von 6b-d invertiert ist. Der Einsatz von [D2]-1a zeigte, daß die Addition von Thiophenol stereochemisch nicht einheitlich verläuft. Bei der Einwirkung von Thiophenol auf 1a bei 20°C ohne Belichtung bildeten sich in langsamer Reaktion neben 6a auch die Norcaren-Derivate 9 und 10. - Die Umsetzung der Dichlorverbindung 6b mit LiAlH4 führte zur Monochlorverbindung 6h. 6b und mit besserer Ausbeute 6h gingen mit Natrium in flüssigem Ammoniak in unsubstituiertes Norpinen (11a) über, für das somit eine ergiebige neue Synthese zur Verfügung steht. Auf diese Weise wurden auch 6c, d in 4-Phenylnorpinen (11b) umgewandelt. Die Reaktionen der Norpinene 3a und 11a mit N-Bromsuccinimid ergaben die Allylbromide 3d und 11c. - Die 13C-NMR-Spektren der 4-substituierten Norpinene brachten einen diagnostisch wichtigen γ-anti-Substituenteneffekt an den Tag.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861191011
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  • 195
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    Tricyclo[5.1.0.02,8]oct-3-en, -oct-4-en und -octan: Darstellung und Thermolyse der Hydroderivate des Octavalens (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 3045-3058 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Tricyclo[5.1.0.02,8]-oct-3-ene, -oct-4-ene, and -octane: Preparation and Thermolysis of the Hydro Derivatives of OctavaleneOn treatment of 2,3,7,8-tetrabromobicyclo[4.1.1]oct-3-ene (7) with LiAlH4 an allylic rearrangement occurred with formation of tribromide 8, which was converted into 4-bromotricyclo[5.1.0.02,8]oct-3-ene (9) by n-butyllithium. Sodium/tert-butyl alcohol and 9 reacted to give tricyclo[5.1.0.02,8]oct-3-ene (4). Hydrogenation of 4 was achieved with diimine and afforded tricyclo[5.1.0.02,8]octane (6) along with some bicyclo[5.1.0]oct-2-ene (10). Sodium iodide transformed 7 into the unrearranged iodide 12. Reduction of 7 with sodium in liquid ammonia led to bicyclo[4.2.0]octa-3,7-diene (11) in low yield. An allylic rearrangement took place when 7 was treated with AgNO3 to give nitrate 13. In another allylic rearrangement tribromide 14 was formed from 13 and LiAlH4. The reaction of 14 with n-butyllithium afforded 4-bromotricyclo[5.1.0.02,8]oct-4-ene (15), and from 15 tricyclo[5.1.0.02,8]oct-4-ene (5) was obtained by means of sodium/tert-butyl alcohol. By treatment of 4-bromooctavalene (16) with tert-butyllithium and subsequent hydrolysis, a new route to octavalene (1) was elaborated with virtually no formation of cyclooctatetraene as side product. - At 100°C 4 rearranged (t1/2 ≍ 40 min) almost quantitatively to dihydrosemibullvalene (17). The decomposition of 5 at 200°C (t1/2 ≍ 25 h) gave a complex mixture, in which only 11 has been identified. The saturated hydrocarbon 6 was converted virtually quantitatively into a 5.5:1 mixture of 3-methylenecycloheptene (18) and 1,3-cyclooctadiene (19) at 160°C (t1/2 ≍ 8 h). Possible mechanisms of these rearrangements are discussed.
    Notes: 2,3,7,8-Tetrabrombicyclo[4.1.1]oct-3-en (7) ging mit LiAlH4 unter Allylumlagerung in das Tribromid 8 über, das bei der Einwirkung von n-Butyllithium 4-Bromtricyclo[5.1.0.02,8]oct-3-en (9) lieferte. Letzteres ergab mit Natrium/tert-Butylalkohol Tricyclo[5.1.0.02,8]oct-3-en (4). Die Hydrierung von 4 zu Tricyclo[5.1.0.02,8]octan (6) wurde mit Diimin ausgeführt und war von der Bildung von Bicyclo[5.1.0]oct-2-en (10) begleitet. Mit Natriumiodid brachte 7 das nicht umgelagerte Iodid 12 hervor, und die Reduktion von 7 mit Natrium in flüssigem Ammoniak führte in geringer Ausbeute zu Bicyclo[4.2.0]octa-3,7-dien (11). AgNO3 wandelte 7 unter Allylumlagerung in das Nitrat 13 um, das mit LiAlH4, wieder unter Allylumlagerung, das Tribromid 14 ergab. Bei der Behandlung von 14 mit n-Butyllithium fiel 4-Bromtricyclo[5.1.0.02,8]oct-4-en (15) an, und daraus wurde mit Natrium/tert-Butylalkohol Tricyclo[5.1.0.02,8]oct-4-en (5) gewonnen. Ein neuer Weg zu Octavalen (1), auf dem praktisch kein Cyclooctatetraen als Nebenprodukt entsteht, wurde durch Umsetzung von 4-Bromoctavalen (16) mit tert-Butyllithium und anschließende Hydrolyse gefunden. - Bei 100°C ging 4 praktisch quantitativ in Dihydrosemibullvalen (17) über (t1/2 ≍ 40 min). Der Zerfall von 5 lieferte bei 200°C (t1/2 ≍ 25 h) ein komplexes Gemisch, in dem nur 11 identifiziert wurde. Der gesättigte Kohlenwasserstoff 6 lagerte bei 160°C nahezu quantitativ in ein 5.5:1-Gemisch aus 3-Methylencyclohepten (18) und 1,3-Cyclooctadien (19) um (t1/2 ≍ 8 h). Mögliche Mechanismen dieser Thermolysen werden diskutiert.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861191012
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    Laserfarbstoffe, IV. Synthese planar fixierter Nonamethin-Cyaninfarbstoffe (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 3102-3108 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Laser Dyes, IV. Synthesis of Plane Rigidized Nonamethine Cyanine DyesThe one-pot synthesis of symmetrical and unsymmetrical nonamethine cyanine dyes 2 with a plane rigidized methine chain is described.
    Notes: Es wird ein Eintopf-Verfahren zur Darstellung von symmetrischen und unsymmetrischen Nonamethin-Cyaninfarbstoffen 2 mit planar fixierter Methinkette beschrieben.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861191017
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  • 197
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    Reaktionen der Cyclopropene, VII. Nickel(0)-katalysierte Cotrimerisierungen von 3,3-Dimethylcyclopropen mit Methylacrylat (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 3089-3101 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of Cyclopropenes, VII. Nickel(0)-catalyzed Cotrimerisation of 3,3-Dimethylcyclopropene with Methyl AcrylateThe cotrimerisation of 3,3-dimethylcyclopropene (1) with methyl acrylate is catalyzed by phosphane- or phosphite-Ni(0) compounds under mild conditions (40-50°C). Depending on the nature of the phosphane or phosphite 1 and methyl acrylate cotrimerise mainly in the ratio 2:1 or 1:2 to give cis/trans-5 or cis/trans-6 and cyclic cis/trans-7. trans-5 and trans-6 are thermally more labile than the corresponding cis compounds. Heating to 200°C for two hours induces their complete rearrangement to 12 and 13 or 14 via 1,5-homodienyl-hydrogen shift.
    Notes: Triorganylphosphan- und -phosphit-haltige Nickel(0)-Verbindungen katalysieren die Cotrimerisierung von 3,3-Dimethylcyclopropen (1) mit Methylacrylat unter milden Bedingungen (40-50°C). In Abhängigkeit von der Art des Phosphans bzw. Phosphits entstehen bevorzugt offenkettige Cotrimere aus einem Mol 1 und zwei Mol Methylacrylat (cis/trans-5) oder offenkettige und cyclische Cotrimere aus zwei Mol 1 und einem Mol Methylacrylat (cis/trans-6 und cis/trans-7). trans-5 und trans-6 sind thermisch deutlich labiler als die entsprechenden cis-Derivate. Im Zuge einer 1,5-Homodienylwasserstoffwanderung lagern sie sich bereits nach zweistündigem Erhitzen auf 200°C quantitativ in die entsprechenden 1,4-Diene um (12 und 13 aus trans-5 bzw. 14 aus trans-6).
    Additional Material: 7 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861191016
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    Umlagerungen und komplexe Eliminierungen mit 1,5-Benzothiazepin-4-onen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 3109-3120 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Rearrangements and Complex Eliminations with 1,5-Benzothiazepin-4-onesThe 1,5-benzothiazepin-4-ones 3, 5, and 7-10 are pyrolyzed (with proton catalysis in part). New or rarely documented rearrangements and complex eliminations occur. These are classified and mechanistically discussed. The products and by-products are spectroscopically characterized (IR, UV, NMR, MS). Their configurations are elucidated via photolysis experiments. 4 photodimerizes in solution and in the crystalline state with great ease to give 14. 11 is remarkably insensitive towards hydrolysis.
    Notes: Die 1,5-Benzothiazepin-4-one 3, 5 und 7-10 werden pyrolysiert (z. T. bei Protonenkatalyse). Es treten neue oder selten dokumentierte Umlagerungsreaktionen und komplexe Eliminierungsreaktionen auf, die klassifiziert und mechanistisch diskutiert werden. Die Produkte und Nebenprodukte werden spektroskopisch charakterisiert (IR, UV, NMR, MS) und mittels Photolyse in ihrer Konfiguration geklärt. 4 photodimerisiert sehr leicht in Lösung oder im Kristall zu 14. 11 ist erstaunlich hydrolyseunempfindlich.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861191018
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    Übergangsmetall-substituierte Acylphosphane und Phosphaalkene, IX. Zur Synthese von Phosphaalkenyl-, Mono- und Diacyl- phosphidokomplexen aus [Bis(trimethylsilyl)phosphido]-dicarbonyl(pentamethylcyclopentadienyl)eisen und Carbonsäurechloriden (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1857-1867 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Transition-Metal-Substituted Acylphosphanes and Phosphaalkenes, IX. On the Synthesis of Phosphaalkenyl-, Mono- and Diacylphosphido Complexes from the Reaction of [Bis(trimethylsilyl)phosphido]dicarbonyl(pentamethylcyclopentadienyl)iron and Carbonyl ChloridesReaction of the title compound (η5-C5Me5)(CO)2FeP(SiMe3)2 (4) with 2,4,6-trimethylbenzoyl chloride (2a) yields the phosphaalkenyl complex (η5-C5Me5)(CO)2FeP=C(OSiMe3)(Mes) (5a). Treatment of 4 with benzoyl chloride affords the phosphaalkenyl complex 5b and (η5-C5Me5)(CO)2FeP[C(O)Ph]2 (6b), whereas with pivaloyl chloride (2c) 6c is formed as the sole product. The monoacylphosphido complexes 8a-c are generated from the reaction of 4 with acyl chlorides 2a-c in the presence of ethanol. Lithiation by LiCH3 and subsequent acylation with 2,4,6-trimethylbenzoyl chloride converts compound 8a into 6a. Similarily the lithiation product of 8 is transformed into the phosphaalkenyl complexes 5a-c by treatment with Me3SiCl.
    Notes: Die Titelverbindung (η5-C5Me5)(CO)2FeP(SiMe3)2 (4) reagiert mit 2,4,6-Trimethylbenzoylchlorid (2a) zu dem Phosphaalkenylkomplex (η5-C5Me5)(CO)2FeP=C(OSiMe3)(Mes) (5a). Demgegenüber führt die Umsetzung von 4 mit Benzoylchlorid neben dem Phosphaalkenylkomplex 5b zu (η5-C5Me5)(CO)2FeP[C(O)Ph]2 (6b). Aus 4 und Pivaloylchlorid (2c) wird nur noch der Dipivaloylphosphidokomplex 6c gebildet. Führt man die Umsetzungen von 4 mit den Säurechloriden 2a-c in Gegenwart von Ethanol durch, so erhält man die Monoacylphosphidokomplexe (η5-C5Me5)(CO)2FePH[C(O)R] (8a-c). Komplex 8a wird von Methyllithium lithiiert und durch 2,4,6-Trimethylbenzoylchlorid in 6a übergeführt. Desgleichen ergeben die Lithiierungsprodukte von 8 mit Me3SiCl die Phosphaalkenylkomplexe 5a-c.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190608
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    Additionsreaktionen von 1,1-Dicyan-2,2-bis(trifluormethyl)ethen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 3150-3157 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Addition Reactions of 1,1-Dicyano-2,2-bis(trifluoromethyl)etheneBy the reaction of the title compound (CF3)2C=C(CN)2 with PCl5 the (phosphoranyliden-amino)ethene 1 is obtained. The phosphorane 1 reacts with Me3SiNMe2 to form 2. WCl6 and MoCl5 react with (CF3)2C=C(CN)2 to give the acyclic nitrenes 3 and 4. The X-ray structure analysis of 3a, an acetonitrile adduct of 3, is reported.
    Notes: Die Titelverbindung (CF3)2C=C(CN)2 reagiert mit PCl5 zu dem (Phosphoranylidenamino)-ethen 1. Daraus entsteht 2 durch Reaktion mit Me3SiNMe2. Umsetzungen von (CF3)2C=C(CN)2 mit WCl6 und MoCl5 ergeben die acyclischen Nitrenkomplexe 3 und 4. Von 3a, einem Acetonitriladdukt von 3, wird eine Röntgenstrukturanalyse mitgeteilt.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861191022
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