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  • 1985-1989  (2,413)
  • 1988  (2,413)
  • General Chemistry  (1,050)
  • Organic Chemistry  (765)
  • Engineering  (598)
  • 1
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 115-117 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A novel oxygen induced reduction of α,β-unsaturated carbonyl compounds is discovered. The reduction of the carbon-carbon double bond of α,β-unsaturated carbonyl compounds by benzeneselenol was caused by an introduction of molecular oxygen into the reaction system. This reduction is likely to proceed via a radical chain pathway involving an SH2 type reaction between a phenylseleno radical and a 1,2-adduct of benzeneselenol to the carbonyl group of the α,β-unsaturated carbonyl compound to give an allylic radical which absracts a hydrogen atom from benzeneselenol to form the reduction product.
    Additional Material: 1 Tab.
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  • 2
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 191-195 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The photochemical reaction of MAQO with various aromatic amines were studied by ESR. The results show that nitroxide radicals are stable productrs of the photooxidation of both diphenylamines and phenylamines. The photolyzed phenothiazine does not yield nitroxide as the final product, instead it gives the neutral radical as the stable final product.
    Additional Material: 4 Ill.
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  • 3
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 333-349 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: New series of platinum complexes of cyclopropenylidenes of the types of PtX2(CP)2 and trans-PtX(PBu3)2(CP) have been synthesized, where CP is di-t-butylcyclopropenylidene (BCP) or bis(diisopropylamino)cyclopropenylidene (ACP). The 13C-NMR chemical shifts, and 13C-195Pt coupling constants (1JPtC) for the complexes are discussed in comparison with those values derived from closely related series of compounds, trans-PtCl(PR3)2L; L — —CH3, —C6H5 and —C≡CBu-t. An excellent linear relationship through the origin was obtained between 1JPtC and the formal ‘s’ % character of the carbon directly bonded to Pt for the series trans-PtCl(PR3)2L in which the Pt—C bond is regarded as a pure σ-linkage, whereas 1JPtC deviates largely from this relationship when pπ—dπ bonding interaction possibly exists in the Pt—C bond. The NMR data suggest the strong nmr trans-influence of the cyclopropenylidenes and that in the Pt—CP bond the σ-interaction is appreciable but the π-interaction is negligible.
    Additional Material: 3 Ill.
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  • 4
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988) 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 123-131 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Photolysis of N-alkyl-N-(3-aryl-3-butenyl) ureas (1) in acetonitrile gave cyclization products, 3-aryl-3-methyl-pyrrolidines, in good yields, whereas irradiation of 1 in methanol afforded methanol adducts as well as the cyclization products. Both the reactions are singlet reactions, and the cyclization is presumed to proceed via 1,6-hydrogen transfer from exciplexes with charge transfer character.
    Additional Material: 2 Tab.
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  • 6
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 143-151 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The dependence of the catalytic efficiencies of sodium carboxymethylamylose (NaCMA) for the hydrolysis of N-lauryl-3-acetoxypyridinium iodide (1) and p-nitrophenyl dodecanoate (3) on its degree of substitution (D. S. = 0·00, 0·12, 0·18, 0·24, 0·29 and 0·35) and on the pH values of the solutions (pH = 7·32, 7·80, 8·10 and 9·30) have been studied. At fixed D. S. values, the observed hydrolysis rates of 1 and 3 increase with increasing concentrations of NaCMA and follow saturation kinetics. At fixed concentration of NaCMA, the rates increase with decreasing D. S. values until they reach maxima at D. S. = 0·00. Furthermore, at any D. S. value the catalytic efficiency increases with increasing pH values of the solutions. All these results indicate that the hydroxyl groups are actually the principal catalyzing groups.
    Additional Material: 5 Ill.
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  • 7
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988) 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 169-178 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The development of positive charge β to silicon in a saturated five-membered ring has been studied in the cis- and trans-2-(trimethylsilyl)cyclopentyl trifluoroacetates. The cis substrate solvolyzes in 97% trifluoroethanol at 25° C about 5 times faster than the analogous six-membered ring, after correction for differences in ring strain. The trans substrate solvolyzes about 360 times more slowly than the analogous six-membered ring. These changes are in agreement with a hyperconjugative mechanism for interaction between the silyl group and the developing positive charge. The expected cosine-squared dependence of hyperconjugation on the Si—C—C—X dihedral angle suggests that the cis dihedral angle is reduced somewhat from the 60° in the six-membered ring, and the trans dihedral angle is reduced substantially from the 180° in the six-membered ring.
    Additional Material: 3 Ill.
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  • 9
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 209-223 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The equilibrium acidities of phenylacetonitrile, and 20 of its m- and p-substituted derivatives have been measured in Me2SO solution. Their pKa′s plot linearly with those of the corresponding anilines. Combination of the pKa′s of these acids with their oxidation potentials, Eox(HA), and those of their conjugate bases, Eox(A-), provide an estimate of the acidities of the corresponding radical cations. The pKHA+ values for ArCH2CN+., where Ar is Ph, 1- and 2-naphthyl, and 9-anthryl, are -32, -18·5, -17·5, and -11, respectively, compared to 21·9, 20·85, 20·65, and 19·8 for the corresponding ArCH2CN acids. Acidities of PhCH(Me)CN+., Ph2CHCN+., 9-CN-FlH+., and 9-CN-XnH+. are -33, -35, -25, and -27, respectively, compared to 23·0, 17·5, 8·3, and 13·6 for the corresponding acids from which they were derived. The homolytic bond dissociation energies (BDEs) for the benzylic C—H bonds in these arylacetonitriles, estimated by combining pKHA with Eox(A-), fall in the range of 69 kcal/mol for 9-CN-XnH to 82 kcal/mol for PhCH2CN. For GC6H4CH2CN+. radical cations the acidities are decreased, relative to G=H, when G is an electron donor substituent and increased when G is an acceptor. The BDEs of the benzylic C—H bonds in GC6H4CH2CN are weakened by up to 4 kcal/mol by para donors and strengthened by up to 1·2 kcal/mol by m- or p-acceptors. The significance of these changes in BDEs with regard to the use of σ. scales and the ΔAOP method for estimating substituent effects on radical stabilities is discussed.
    Additional Material: 5 Ill.
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  • 10
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 259-265 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: 1-(Phenylazo)-1-(2-pyridyl)ethyl hydroperoxide, 1, 1-(phenylazo)-1-(2-furyl)ethyl hydroperoxide, 2, phenylazo(2-furyl)methyl hydroperoxide, 3, 1-(phenylazo)-1-(4-anisyl)ethyl hydroperoxide, 4, were synthesized in moderate yield by autoxidation of the phenylhydrazones in benzene. The ionic oxidation of benzyl methyl sulfide in benzene by 1-4 yielded the sulfoxide and the metastable α-azo hydroxides in essentially quantitative yield. The reaction was of the first order in α-azo hydroperoxide and sulfide, respectively. The relative reactivity series found was: 1(1.0) 〈4(1.4) 〈 phenylazo(4-anisyl)methyl hydroperoxide 5 (2·9) 〈2 (3·8) 〈 3 (9·6). α-Methyl substitution was found to slow the rate of oxygen-atom trasfer by a factor of 2 to 2.5. The low relative reactivity of 1 was opposite that expected based on electronic effects. Competitive intramolecular hydrogen bonding of the hydroperoxy proton to the pyridyl nitrogen in 1 accounted for the observed result.
    Additional Material: 2 Tab.
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  • 11
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 281-285 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The thermal and photochemical decompositions of 5 have been studied. Both reactions lead to CBr2 transfer in good to high yields. With the 2-pentenes as substrates, CBr2 transfer is stereospecific in the classical singlet carbene manner.
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  • 12
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 305-308 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Decomposition of the tosylhydrazone salts formed from cubyl carboxaldehyde and homocubanone, potential precursors of cubylcarbene (5) and homocubanylidene (6), leads in each case to products derived from 6. It is suggested that homocub-1(9)-ene (7) is the active ingredient in the formation of 6 from both precursors. The hydrazones formed from N-aziridylamines are useful photochemical sources of 6, and presumably other carbenes. Flash vacuum pyrolysis of the tosyl hydrazone salts and hydrazones at 600°C leads to indene.
    Additional Material: 1 Tab.
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  • 13
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 317-332 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Light- and heat-induced decompositions and reactions with nucleophiles of 6,6,8,8-tetramethyl-2-selena-3,4-diaza-7-oxabicyclo[3.3.0]octa- 1(5),3-diene have been studied. In contrast with the conversion to the cyclopentyne derivative (9), selenium containing intermediates (6a, 6b, and 7) were efficiently trapped using several reagents to give various kinds of organoselenium compounds. Of particular note is the isolation of a stable selenirane derivative (16) obtained by the cycloaddition of the photochemically generated selenirene intermediate (7) with furan. The character and reactivity of the intermediates are also discussed.
    Additional Material: 3 Tab.
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  • 14
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 359-362 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Reaction rates for solvolysis of a mustard analogue are accurately correlated by the solvatochromic equation without inclusion of a nucleophilicity term, and thus the equation is shown to reveal mechanistically significant information.
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  • 15
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988) 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
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  • 16
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 247-257 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The rate of hydrolysis of the aromatic vinyl ether o-carboxy-α-methoxy-β,β-dimethylstyrene was found to be accelerated 25-fold by ionization of its carboxylic acid group, but the effective molarity which may be calculated if all of this rate acceleration is ascribed to intramolecular general acid catalysis is only EM = 1 · 1 m. This is similar to the small effective molarities found before for intramolecular catalysis by carboxylic acid groups of aliphatic vinyl ethers, which shows that, unlike the situation in other intramolecular reactions, e.g. ketone enolization, the extra rigidity of aromatic over aliphatic systems does not improve the efficiency of intramolecular catalysis in vinyl ether hydrolysis.It is suggested that this behaviour is the result of reduced conjugation between the vinyl ether group and the aromatic ring in the transition state of the vinyl ether hydrolysis reaction, which retards the rate and offsets any improvement effected by increased rigidity of the aromatic system.
    Additional Material: 2 Ill.
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  • 17
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: 2,2′-Diselenocyanato-1,1′-binaphthyl(1), the first selenium-containing binaphthyl derivative, has been synthesized in optically active form the corresponding diamine by diazotization followed by the reaction with potassium selenocyanate. Its molecular structure is determined by X-ray diffraction method. It is revealed that selenium atoms have hypervalent penta-coordination in the crystal.
    Additional Material: 4 Ill.
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  • 18
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 287-298 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Ab initio STO-3G and 6-31G minimized geometries of 5-oxo- (9), 6-oxo-7-oxabicyclo[2.2.1]hept-2-yl cation (12) and 7-oxabicyclo[2.2.1]hept-2-yl cation (15) were obtained. The energy barriers for their Wagner-Meerwein rearrangements to the more stable 5-oxo- (11), 6-oxo-3-oxabicyclo[2.2.1]hept-2-yl (13) and 3-oxabicyclo[2.2.1]hept-2-yl (17) cations, respectively, have been evaluated and compared with those calculated for the rearrangement of the 5-oxo (18) and 6-oxobicyclo[2.2.1]hept-2-yl cations (20). In agreement with experimental data, the ‘true migratory aptitude’ of an acyl group is higher than that of β-oxoalkyl group in competitive Wagner-Meerwein rearrangments that are ‘energetically unbiased’. The ease of the acyl group 1,2-shift toward an electron-deficient center is related to the electron-donating ability of the carbonyl group due to favorable n(CO) ↔ σ σ ↔ p(C+) hyperconjugative interaction.
    Additional Material: 1 Ill.
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  • 19
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 299-303 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Iodide ion promotes the free radical reaction of isopropylmercury idide with bromotrichloromethane to yield isopropyl bromide with rate enhancement in the order of 104. The reaction involves electron transfer from i-PrHgI2- to the trichloromethyl radical in a long kinetic chain process. Iodide ion also promotes the free radical chain conjugate addition of tert-butylmercury chloride to α,β-unsaturated ketones, esters, phosphonate esters and sulfones. Competitive reactivity studies indicate that lithium di-tert-butylcuprates or tri-tert-butylzincates react with 2-cycloalkenones by a mechanism involving attack by tert-butyl radicals. No evidence for radical attack is observed for the corresponding n-butyl ate complexes of copper or zinc.
    Additional Material: 1 Tab.
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  • 20
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 103-114 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The effect of solvent additives on the course of TiO2 photocatalyzed oxygenation of α-methylstyrene has been studied. While the addition of small amounts of nonhalogenated alcohols to TiO2 powders suspended in acetonitrile was found to decrease the rate of photooxygenation, added halogenated alcohols increase the rate of reaction. In addition, the solvent additives affect the observed product distribution.
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  • 21
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    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 119-121 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Reduction of aromatic aldehydes by benzeneselenol is found to be promoted by molecular oxygen to give corresponding alcohols in good yields. No reduction took place without oxygen.A free radical process involving SH2 reaction at the selenium atom is proposed where the phenylseleno radical attacks the selenium atom of selenohemiacetal, the adduct of benzeneselenol to aldehyde, to give the ketyl radical which then abstracts hydrogen from benzeneselenol. The intermediacy of selenohemiacetal is supported by a quantitative reduction of α-methoxybenzyl phenyl selenide, which is used as a model compound of the intermediate.
    Additional Material: 1 Tab.
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  • 22
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The dependency of the wrapping-up capability of sodium carboxymethylamylose (NaCMA) on its degree of substitution (D. S. = 0·00, 0·12, 0·18, 0·24, 0·29, 0·35 and 0·41) have been studied, using two guest species, iodine and cetyl-trimethylammonium bromide (CTAB). The λmax values of NaCMA-iodine helical inclusion complexes decrease with increasing D. S. values and the amounts of encapsulated iodine by NaCMA as measured by amperometric titrations also decrease with increasing D. S. values. With CTAB as the substrate, the largest number of binding sites, n, and the dissociation constants Kd have been determined by the method of surface tension versus the CTAB concentration plots. The results show that n decreases while Kd increases with increasing D. S. values. All these observations point to the fact that the wrapping-up capability of NaCMA decreases with increasing degrees of substitution. The results are discussed in terms of host-guest and host-solvent hydrophobic-lipophilic interactions as well as intramolecular hydrogen-bonding.
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  • 23
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    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 161-167 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The temperature-dependence of the kinetic isotope effects for branched reactions proceeding via a common intermediate has been simulated by calculations. It is shown that, under certain conditions, anomalously small isotope effects on the Arrhenius preexponential factors, as well as unusually large observed isotope effects, may originate from the branching.
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  • 24
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    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 153-160 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The structures of the allyl anion (1) and two fluoro-substituted derivatives, perfluoro (2) and 1,1-difluoro (3) have been calculated by ab inito molecular orbital theory. Geometries were gradient optimized, and force fields and an MP-2 correlation correction were determined at stationary points. The calculations were done with a double zeta basis set augmented by d functions on carbon (DZ + Dc). Final self-consistent field (SCF) and MP-2 energy calculations were done with the DZ + Dc basis set augmented by diffuse functions. The ground state of 1 is the planar allyl anion (C2v). The rotation barrier in 1 is 21·1 kcal/mol at the MP-2 level. The cyclopropyl carbanion is 27·0 kcal/mol higher in energy at the MP-2 level. The perfluoroallyl anion is not planar, and the rotated structure is 25·7 kcal/mol more stable than the C2v structure at the MP-2 level. The lowest energy structure on the potential energy surface for 2 is the perfluorocyclopropyl carbanion which is 27·8 kcal/mol more stable than the C2v structure at the MP-2 level. The 1,1-difluoroallyl anion is also not planar. Here the most stable structure on the potential energy surface is the rotated allyl anion which is 8·3 kcal/mol more stable than the all-planar allyl anion structure.
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  • 25
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    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 241-245 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The rates of solvolysis of l-aryl-l-phenyl-2,2-dimethylpropyl(1) p-nitrobenzoates and of aryldiphenylmethyl-p-nitrobenzoates (2) were measured in 80% acetone. An inverse order of reactivity, kp-CF3/km- CF3 〉 l was observed for 1 but not for 2. The X-ray crystallogoraphic study of the parent compounds, l,l-diphenyl-2,2-dimethylpropyl-p-nitrobenzoate (1b) and triphenylemethyl benzoate (3b), and of 2-phenyl-2-propyl-p-nitrobenzoate (4) indicated that in the highly congested system 1 both phenyl rings were nonplanar, whereas the phenyl rings in 3 and 4 were essentially planar.
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  • 26
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    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 185-190 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: From the 1H-NMR spectra of the various pyrrole compounds, 1-substituted 2,5-dimethylpyrroles having two substituent groups on the carbon adjacent to the nitrogen atom were found to be very much hindered compounds. 1-[(1-Substituted)-2-phenylethyl]-2,5-dimethylpyrroles showed the restricted rotation, and the phenyl group of the most stable conformer was in close proximity to the pyrrole group due to dipole interaction. These NMR observations were supported by force field conformational analysis.
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  • 27
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    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 197-207 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: ESR spectra of l-cyano-2-(trimethylsilyl)ethyl and related radicals were recorded. Temperature dependent ESR spectra of these radicals revealed that electron-releasing trimethylsilylmethyl and electron-withdrawing cyano groups synergetically functioned to stabilize the radical centers due to σ-π captodative effects.
    Additional Material: 10 Ill.
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  • 28
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The excellent linearity (R2 = 0·997) of a plot of pKa values for 17 m- and p-substituted benzyl phenyl sulfones, GC6H4CH2SO2Ph, vs. those for the corresponding arylacetonitrile, GC6H4CH2CN, demonstrates that substituent solvation and substituent solvation assisted resonance (SSAR) effects for p-CN, p-COPh, and p-SPh are nearly identical in these two substrates. The PhSO2 group in PhCH2SO2Ph increases the BDE of the α-C—H bond by 2 kcal/mol, relative to toluene. The α-C—H bonds in GC6H4CH2SO2Ph sulfones are stabilized by 1-2 kcal/mol by acceptor G′s (m-CN, p-CN, m-CF3, p-CF3), but weakened by 1 and 5 kcal/mol, respectively, by donors (p-OMe and p-NMe2). The GC6H4CH2SO2Ph+. radical cation with G = H has a pKHA+. = -25. Its acidity is increased when G is an acceptor by as much as 9 to 10 kcal/mol (G = 3-CN, 3-CF3, 4-CF3, 4-NO2), but is decreased when G is a donor by as much as 33 kcal/mol (G = NMe2). When G = 4-SPh the radical cation is stabilized, relative to G = H, by a larger amount (25 kcal/mol) than when G = 4-OMe (18 kcal/mol). Structural changes along the series PhCH2SO2Ph, 2-naphthyl-CH2SO2Ph, 9-anthryl CH2SO2Ph cause negligible changes in the acidities of these acids, but sizable decreases in the acidities of the corresponding radical cations. Introduction of a phenylsulfonyl group into the methyl group of 9-methylanthracene or the 9-position of fluorene or xanthene increase the BDEs by 3, 2, and 7 kcal/mol, respectively. These effects of PhSO2 groups are compared and contrasted with those of CN groups.
    Additional Material: 3 Ill.
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  • 29
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    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 267-273 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The PE spectra of four stable bicyclic triaziridines with trifluoromethyl, methyl, phenyl, spirocyclopentane and spirocyclohexane substituents are measured. From a comparison of these experimental data with MNDO calculations the energies and the interactions of the nitrogen lone-pair orbitals were obtained. The trifluoromethyl group may be reliably simulated by a fluorine atom. The ionization potentials are unexpectedly high and so are the cyclovoltammetric anodic potentials. The MNDO valence electron densities are in agreement with the comparatively small differences in the chemical shifts of the differently substituted nitrogens of the triaziridine rings.
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  • 30
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    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 275-280 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: In order to examine the substituent effect of ethylenedithio and trimethylenedithio groups on electron acceptors, the two title compounds were prepared in one step from the corresponding quinones. These species behave as weak π-electron acceptors owing to the electronic and sterical effects of the fused groups. Only the bis(ethylenedithio) derivative formed a charge-transfer complex with tetrathiotetracene, which showed a moderate electric conductivity of 2·0 × 10-2 S cm-1. In addition, both species oxidized copper, sodium, and potassium iodides to give the corresponding deeply colored metal salts, most of which were semiconductive. The naphtho analogs were similarly studied, but hardly served as electron acceptors.
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  • 31
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    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988) 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
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  • 32
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Photoresponse of the poly(vinyl chloride) membranes, which contain spirobenzopyran and crown ether, covered with a urease layer was studied in the presence and absence of urea. In the absence of urea, UV light irradiation induced more than 160 mV of membrane potential change, whereas the photoresponse decreased with an increase in the concentration of urea in the solution. The effects of such operating variables as crown loading and pH and ionic strength in the aqueous phase on the potentiometric response were also elucidated in the presence of urea. The results were explicated using the fact that the local concentration on NH4+ and H+ ions changed as a result of the urease-catalyzed decomposition reaction of urea.
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  • 33
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    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 1 (1988), S. 351-357 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The title reaction is an instance of a simple nucleophilic attack of neutral nitrogen on aromatic sp2 carbon. The kinetic data (obtained in dimethyl sulphoxide) are compared to the results reported by the literature for the same reaction of aliphatic amines. Some possible interactions (substrate/nucleophile, substrate/salt) preceding the attack of the nucleophile are discussed.
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  • 34
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 115-128 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: An absorbing boundary condition for simple layered media is presented. The method enables the modelling of open space radiation and scattering problems when the source (or scatterer) and a plane interface between two media are both located within the finite-difference or finite-element region. The projection operator method is used to take into account the presence of reflected waves at the media interface. The derivation of the projection operator is presented for one, two and three dimensions. Examples of electromagnetic radiation and scattering in two dimensions are presented to illustrate the numerical implementation and validity of the new absorbing boundary condition.
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  • 35
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 129-130 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
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  • 36
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    Chichester [u.a.] : Wiley-Blackwell
    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 131-136 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: A design method for filters having duobinary signal pulses as impulse response is presented.
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  • 37
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    Chichester [u.a.] : Wiley-Blackwell
    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 137-151 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Additional Material: 5 Ill.
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  • 38
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 153-164 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Spontaneous emission noise power, although small in magnitude, affects many aspects of the semiconductor laser's operation. An accurate model has been developed for it for use in the transmission-line laser model (TLLM), which is a time-domain, wideband, dynamic, non-adiabatic semiconductor laser model. The effects of approximations used in other dynamic laser models are then investigated by comparison with the results from the TLLM. The study shows that the representation of this noise power has an important bearing on the damping of modelled transient oscillations.
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  • 39
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 171-171 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
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  • 40
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    Chichester [u.a.] : Wiley-Blackwell
    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 165-170 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: A method for analysing the electrical effect of a set of conducting strips is presented. This method is applied to modelling the electrical behaviour of conducting tracks on a printed circuit board (PCB). Unlike most other published work, this analysis is not restricted to the case where the tracks are parallel. The problem is formulated in terms of an admittance matrix. A boundary element method incorporating image theory is used to produce a system of linear equations. These are solved to yield the required admittance matrix, which can then be incorporated into a standard circuit analysis package. Comparisons between measured and predicted circuit performance for a complex layout show close agreement up to at least 1 GHz.
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  • 41
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 173-174 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
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  • 42
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    Chichester [u.a.] : Wiley-Blackwell
    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 175-188 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: The asymptotic form, for high frequencies, of the equations of propagation on a nonuniform N-conductor transmission line is considered. Under the assumption of perfect conditions in uniform, isotropic media, all N propagation velocities are the same, but the characteristic impedance matrix is allowed to vary with position along the line. Closed-form solutions are obtained for some cases of interest.
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  • 43
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 19-30 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: The Boltzmann transport equation is used to derive a set of conservation equations which is capable of describing the electron transport phenomena in a single-valley semiconductor. These conservation equations are averaged over the different valleys of the conduction band to develop another set of equations that can be used to describe accurately the electron transport phenomena in a multi-valley semiconductor, such as GaAs, using the equivalent single-electron gas model whose characteristics are the average weighted characteristics of the constituent gases. The nonstationary effects are included by using energy dependent mobility and electron temperature functions. This program is used to simulate a GaAs MESFET with a 0·5 μm gate length and a 0.2 μm thick active layer. The active layer is doped at 1017 cm-3. A travelling Gunn domain is observed between the gate and the drain. The domain oscillation frequency is much higher than the normal operating frequency of the MESFET. The domain formation's dependence on the gate bias and the active layer thickness are also presented.
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  • 44
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    Chichester [u.a.] : Wiley-Blackwell
    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988) 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
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  • 45
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 61-70 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Two- and three-dimensional electromagnetic resonance calculations have been performed on rising-sun magnetron structures. These calculations have been made using the transmission-line matrix method. Cylindrical coordinates have been used in order to facilitate modelling of the essentially cylindrical device. Recent improvements to the TLM technique, such as the development of the symmetric condensed node for electromagnetics, have been fully exploited. The numerical procedure is described, the modelling process is discussed, and the results obtained are evaluated in comparisons with corresponding empirical data.
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  • 46
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 45-59 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: The conventional transverse resonance method, which has been widely used for the approximate characterization of a number of guiding structures and leaky wave antennas, is formulated in a generalized form. The transverse resonance viewpoint combined with the generalized matrix representation of discontinuities yields a rigorous transverse equivalent circuit of the guiding structure.This technique is used to compute the characteristics of both symmetrical and asymmetrical double slot unilateral finlines in terms of phase constant and characteristic impedance of the dominant as well as higher-order modes. Numerical aspects of this method are discussed.In a double-slot finline structure, a coupled-mode regime is established with the onset of the first higher-order mode in addition to the dominant quasi-TEM mode. Symmetrical structures are simply modelled in terms of even and odd mode characteristics, but a more general coupled-line model, in terms of the C-mode and the II-mode must be applied to asymmetrical coupled finlines.
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  • 47
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 71-72 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
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  • 48
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 85-91 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Transmission-line models (TLMs) for nonlinear reactive components and mutual inductances are derived. The model for nonlinear reactive components is shown to be an improvement on the previous one. TLM results with the mutual inductance model are compared with the exact solution, and good agreement is found.
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  • 49
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 189-206 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: A numerical method using impulse analysis of a transmission-line matrix is used to model the scattering of underwater acoustic waves. The method is demonstrated by observation of plane and curved wavefronts travelling through the medium, and by plane wavefronts being scattered by a reflecting boundary.
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  • 50
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 207-220 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Shooting and bouncing rays (SBR) is a numerical method based on geometric optics developed to compute the electromagnetic scattering from jet inlets and partially open cavity structures. This method is used to study the effects of shaping on the radar cross-section (RCS) of cavities. Two cylindrical cavity structures are analysed: one with a uniform circular cross-section, and the other with a non-uniform cross-section varying from a triangular shape to a circular shape. By bending the longitudinal axis of a cylindrical cavity, a significant reduction in RCS at near axial incidence can be achieved.
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  • 51
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988) 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
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  • 52
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    Chichester [u.a.] : Wiley-Blackwell
    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 1-1 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
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  • 53
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    Chichester [u.a.] : Wiley-Blackwell
    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 7-17 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: The principal features of the modified TLM method such as the asymmetrical condensed node, graded mesh and dispersion characteristics, are briefly presented. Its general application to multiaxial discontinuities in quasi-planar structures is described, and the modelling of bilateral finline T-junctions is demonstrated in particular.
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  • 54
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 3-6 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: The use of models in giving meaning to sense data is described. It is shown that models are essential to human understanding, but that there are no uniquely ‘best’ models. This leads to the discussion of the design of suitable models for engineering use. The role of physical and mathematical models is mentioned, and attention is drawn to geometrical and physical features. It is stated that numerical methods have overriding advantages, one of which is the possibility of numerical experimentation. The modelling of vector fields is discussed and attention is drawn to the ideas of differential geometry which attach the vector field to the space in which it acts. It is shown that variational methods, together with numerical experiments, can be used to derive invariant parameters which give both global and local information about electromagnetic systems in a particularly economical method of computation.
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  • 55
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 31-43 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: The coupling between incident electromagnetic fields and lossless multiconductor transmission systems is studied using transmission-line modelling-(TLM) and the impedance parameters of the transmission system. This calculation is a two-stage procedure:firstly, the field problem is solved, with no conductors present, to give the incident fields; secondly, the multiconductor transmission-line problem is solved using equivalent voltage and current sources representing coupling from the incident fields. Comparison of these results with previously published work shows excellent agreement. The numerical model presented is particularly suitable for studying electromagnetic compatibility problems.
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  • 56
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 73-83 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: A discrete model is developed to describe the diffusion of dopant/impurity in a single semiconductor crystal during Czochralski growth. The basic diffusion mechanism is assumed to be substitutional-interstitial interchange for the impurity, together with self-diffusion of the host atoms. In particular, the model incorporates the complicated conditions that result from the simultaneous growth and diffusion taking place at the crystal/melt interface. The high temperature dependence of the process is also taken into account, together with possible vacancy production to counteract vacancy depletion. The numerical model is explicit in time, and conditions for convergence and stability are considered. Results are presented for chromium doping of growing gallium arsenide crystals, and compared with published experimental data.
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  • 57
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 93-102 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: One- and two-dimensional algorithms for the transient simulation of semiconductor devices are presented which incorporate a solenoidal total current. The paper includes results from one-dimensional simulation of a p-n junction, including forward-to-reverse bias switching and also switching and also switch-on into high injection in an asymmetric structure. A discretization scheme for the two-dimensional formulation is described with details on handling voltage driven terminals and the associated boundary conditions.
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  • 58
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 103-113 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: This paper describes the application of ASTEC3, a general purpose analogue electronic circuit simulation package, to the analysis of thermal properties of given structures. The modelling of each system is considered for both conduction and convection mechanisms, radiation being assumed to play a very minor role in heat dissipation from most electrical circuits. A procedure is given for the modelling of one-, two- and three-dimensional thermal problems which is then used for the simulation of relatively simple examples. The results obtained with ASTEC3 are compared with results determined by using more traditional and independent techniques.
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  • 59
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    Chichester [u.a.] : Wiley-Blackwell
    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988) 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
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  • 60
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    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988), S. 221-238 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: The development of numerical models to describe physical problems with irregular boundaries frequently involves the use of very fine or variable Cartesian meshes when a more descriptive mesh might be appropriate. This paper describes the application of the transmission line matrix (TLM) technique to the analysis of orthogonal curvilinear mesh problems. Although very high levels of accuracy are possible, the computational efficiency may be reduced owing to the stub admittance factor, S, and the need for an accurate evaluation of the transmission line parameters.
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  • 61
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    Chichester [u.a.] : Wiley-Blackwell
    International Journal of Numerical Modelling: Electronic Networks, Devices and Fields 1 (1988) 
    ISSN: 0894-3370
    Keywords: Engineering ; Electrical and Electronics Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology
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  • 62
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    Journal of Physical Organic Chemistry 1 (1988), S. 21-27 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The structure of radical intermediates appearing in the reactions of MeMgBr with aromatic monoketones was investigated by using ESR and visible spectroscopy. Stable radical intermediates in the reacting solutions were assigned to the dimeric radical ion pairs.
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  • 63
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    Journal of Physical Organic Chemistry 1 (1988), S. 33-38 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Several Cotton effects are developed within absorption bands of trinuclear organotransitionmetal complexes in the presence of acids, diols, amines and aminoalcohols even in the case of bulky substituents on nitrogen; with monohydroxy compounds no circular dichroism could be detected.
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  • 64
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    Journal of Physical Organic Chemistry 1 (1988), S. 29-31 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The Disparity reaction proposed in a recent application of Marcus-Grunwald theory to nitroalkane ionization is shown to put the reaction's transition state in an energy-diagram region where electronic rearrangement leads proton transfer, contrary to experimental evidence; it is suggested that addition of solvent reorganization to electronic rearrangement as the second reaction progress variable would remedy this situation.
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  • 65
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    Journal of Physical Organic Chemistry 1 (1988), S. 39-46 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Triethylsilyl radical was generated by laser flash photolysis of a 1:1 (v/v) solution of triethylsilane and di-tert-butyl peroxide. The silicon centered radical was reacted with sulfides to give carbon centered radicals by displacement at sulfur. The carbon radicals were readily detected by their transient absorption spectra. The absolute rate of reaction of triethylsilyl radical with 9-fluorenylphenylsulfide, di-n-butylsulfide, di-sec-butyl sulfide, di-tert-butyl sulfide and di-n-butyl disulfide are 2.40 ± 0.12 × 108 M-1S-1, 1.1 × 107±0.89×106M-1S-1, 8.79± 0.73×106M-1S-1, 3.29±0.18×106 M-1S-1, and 3.41±0.09×108 M-1S-1, respectively.
    Additional Material: 8 Ill.
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  • 66
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    Journal of Physical Organic Chemistry 1 (1988), S. ii 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
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  • 67
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    Journal of Physical Organic Chemistry 1 (1988) 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
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  • 68
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    Journal of Physical Organic Chemistry 1 (1988), S. 1-20 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Substrates with neutral leaving groups undergo unimolecular solvolysis in nonpolar solvents. Whereas t-alkyl substrates invariably solvolyze by a unimolecular mechanism, s-alkyl and primary alkyl substrates can undergo both uni and bimolecular reactions, and the bimolecular step can take place on either the substrate itself or on an intimate ion-molecule pair formed in either a pre-equilibrium or in a rate determining step. Study of reactions at borderlines indicates that the individual reaction types remain distinct and do not merge.
    Additional Material: 6 Ill.
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  • 69
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    Journal of Physical Organic Chemistry 1 (1988), S. 59-61 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Treatment of α, α′ -diketo selenides, which recently became readily obtainable, with base affords α-oxo selenoaldehydes and ketones. The seleno-carbonyl compounds thus formed are reactive transient species, but can be trapped by Diels-Alder reaction to give 3,6-dihydro-2H-selenapyran derivatives in moderate to good yields.
    Additional Material: 1 Tab.
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  • 70
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    Journal of Physical Organic Chemistry 1 (1988), S. 47-51 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: This paper describes the synthesis and electrochemical behavior of dicationic salts of ethenediylidene-2,2′ -bis(1,3-dithiole) (3) and butatriene-1,4-diylidene-2,2′ -bis(1,3-dithiole) (4). These are expected as donor components for developing organic conducting and superconducting materials, on the grounds of high electron donating ability and of rigid skeletal structure with two and four cumulenic carbons inserted between two 1,3-dithioles. These salts were obtained in good overall yields by several steps starting from (2-morpholino-4,5-dimethyl or -diphenyl)-1,3-dithiolylium salt. From the 1H and 13C NMR, and electronic spectra it is suggested that the π conjugation between two 1,3-dithiolylium ions through an acetylenic bond is less effective than that through an olefinic bond of the corresponding salts of ethanediylidene-2,2′ -bis(1,3-dithiole) (1) and 2-butene-1,4-diylidene-2,2′-bis(1,3-dithiole) (2). The cyclic voltammetric study shows that the corresponding radical cations, and in particular 3 and 4, are less stable even at -40°C, thus providing reasons for our current lack of success in isolation of 3 and 4. From comparison of the first redox potentials of neutral species, it is deduced that the donating ability increases in the order of TTF 〈 1 ⋍ 2 ≲ 3 ≪ 4.
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  • 71
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    Journal of Physical Organic Chemistry 1 (1988), S. 53-57 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The reaction of sulfur ylides with elemental sulfur or selenium initially affords thio- or seleno-carbonyl compounds, which then react with starting ylides to give episulfides or episelenides from which the heteroatom (sulfur or selenium) is extruded to give olefins as the final product. In the case of carbonyl-stabilized ylides, the resulting thio- or seleno-carbonyl compounds react with starting ylides to afford 1,3-oxathioles or 1,3-oxaselenoles as previously reported. Supporting evidence for the intermediacy of thio(seleno)-carbonyl compounds and episulfides (episelenides) is presented.
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  • 72
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    Journal of Physical Organic Chemistry 1 (1988) 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
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  • 73
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    Journal of Physical Organic Chemistry 1 (1988), S. 63-73 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Novel structural features of 5, 15-dialkylporphyrins in solution are described. The 1H-NMR spectra of these compounds showed broad signals at room temperature, which split into two sets of signals at lower temperatures. This unusual phenomenon was ascribed to a dynamic interconversion between tow distorted structures. The 5, 15-dialkylporphyrin has a distorted ring due to the steric hindrance between the 5(or 15)-alkyl group and the 3, 7(or 13, 17)-alkyl groups and, depending on the position of the 5, 15-alkyl groups relative to the average ring plane, can exist in two conformations; syn (where the two alkyl groups are on the same side of the ring plane) and anti (on the opposite sides). Preliminary kinetic study of this interconversion using the NMR line shape analyses is also reported.
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  • 74
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    Journal of Physical Organic Chemistry 1 (1988), S. 75-81 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Highly sterically demanding 2,4,6-tri-t-butylphenyllithium (1) reacts with carbon disulfide to give 1,2-dibutylthio-1,2-bis(2,4,6-tri-t-butylphenylthio) ethene (3), l-butylthio-1-(2,4,6-tri-t-butylphenylthio)pent-l-ene (4), and 2-butylthio-3-(2,4,6-tri-t-butylphenylthio)-1,3-dithiole-2-thione (5) when 1 is prepared by the reaction of 1-bromo-2,4,6-tri-t-butylbenzene with n-butyllithium. When the reaction is carried out using 1 prepared from 2 and t-butyllithium and then quenched with l-iodoethane, 2-ethylthio-3-(2,4,6-tri-butylphenylthio)-1,3-dithiole-2-thione and 1,2-diethylthio-1,2-bis(2,4,6-tri-t-butylphenylthio) ethene are produced. The formation of all these products can be explained in terms of initial thiophilic attack of 1 on the sulfur of carbon disulfide and an intermediate with a dual property of carbanion and carbene (i.e., ArSC(Li)(=S) ⇌ ArSC̈SLi) is suggested. The reaction of 1 with thiophosgene affords 1,2-dichloro-1,2-bis(2,4,6-tri-t-butylphenylthio) ethene, bis(2,4,6-tri-t-butylphenylthio)acetylene, and 1-chloro 2,4,6-tri-t-butylbenzene, the first two of which are explained to be formed by thiophilic attack of 1 with thiophosgene.
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  • 75
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    Journal of Physical Organic Chemistry 1 (1988), S. 91-102 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The photolysis of benzoinalkylethers 1-5 solubilized in detergents show a significant deviation from the course of reaction in isotropic organic solvents. Remarkable difference in photobehaviour is noticed between the short chain (1-3) and the long chain (4 and 5) benzoinalkylethers in the micellar media. However, the influence of the micellar media on the photobehaviour of alkyldeoxybenzoins 6 and 7 was small. The importance of ‘cage effect’ in controlling the product distribution was evident from its dependence on the micellar size and on the occupancy number. More importantly, a comparative analysis of the photobehaviour of the ketone 1-7 reveals that the micellar interface can be used to control the conformations of organic molecules.
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  • 76
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    Journal of Physical Organic Chemistry 1 (1988), S. 83-90 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Theoretical studies on the reactions of ammonia with ketene and dimethylketene using the MNDO method are reported. The single step addition of ammonia to the olefinic bond of ketenes was found to provide a lower energy-barrier path than the two step carbonyl addition mechanism. The barrier height was lower in the reaction of keten compared with that of dimethylketene in support of the faster rate of solution phase reactions of aniline and ketenes. The deformation energies of reactants had an overwhelming influence in determining the activation barriers in all the reactions investigated.
    Additional Material: 4 Ill.
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  • 77
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    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 1-14 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Liquid-Crystalline Heterocycloalkanes. III. Synthesis and Liquid-Crystalline Properties of Substituted 1,3-DioxadecalinesLiquid-crystalline 2-substituted and 2,6-disubstituted 1,3-dioxadecalines (4 - 6) were synthesized by acid-catalyzed acetalization of trans-2-hydroxymethylcyclohexanol (1) or trans-4-alkyl-trans-2-hydroxymethylcyclohexanoles (2) with aldehydes 3 whereby the desired transisomers were formed only. The syntheses of the various aldehydes are also described.Special attention is drawn on the evolution of mesogenic properties of the titlecompounds 4 - 6 in comparison with known decalines and 1,3-dioxanes.It was found that the clearing temperatures of the synthesized 1,3-dioxadecalines are always lower than those of the corresponding decaline derivatives, due to the deformation of the decalineringsystem by the introduction of two oxygen-atoms. The comparison of 1,3-dioxanes and 1,3-dioxadecalines shows that the dioxadecaline ringsystem tends to suppress smectic mesophases in favour of nematics. A first example of a liquid crystalline cis-fused 1,3-dioxadecaline (8) is described, too.
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  • 78
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    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 14-14 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 79
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    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 22-26 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: About the Influence of Pressure on the Catalyzed Liquid-Phase Oxidation of cis- and trans-Oct-4-eneThe investigation of the influence of pressure on the liquid-phase oxidation of cis- and trans-oct-4-ene shows that the reaction rate increases up to 491 kPa in the non-catalyzed oxidation reaction, but up to 981 kPa in the MoO2(acac)2-catalyzed reaction n-oct-1-ene reacts more slowly than cis- and trans-oct-4-ene as well in the pressure-less reaction as in the oxidation under pressure. In the non-catalyzed oxidation reaction the cis/trans- ratios don't depend on the pressure, but in the MoO2(acac)2-catalyzed oxidation reaction the cis/trans-epoxide ratios increase with increasing pressure. The optimum of the reaction temperature lies between 110 and 130°C.
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  • 80
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    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1,2,3-Triazabutadienes. XX. Investigations of the Photochemical Z-E-Isomerization, Photolysis, Protonation and Acidic Cleavage of 1-Aryl-3-3-methylbenzthiazolinyliden-(2)-triazenes in Micellar SolutionsThe E-isomers of the 1-Aryl-3-[3-methylbenzthiazolinyliden-(2)]-triazenes are soluble in aqueous micellar solutions of sodium dodecylsulfate (NDS) and cetyltrimethylammoniumbromide (CTAB). They are fixed in the Stern region of the micelles. The Z-isomers decompose in aqueous micellar solutions by acidic cleavage. They can be stabilized by the use of alkaline buffer solutions. The concentration of protons is higher by the factor 103 in the Stern region of NDS-micelles than in the Stern region of CTAB-micelles. This difference is explained by electrostatic attraction and repulsion between the protons and the micelles. The quantum yields of the photochemical isomerization in micellar solutions and in organic solvents are the same. Water soluble ionic dyes with relatively low triplet energies sensitize the photoisomerization in micellar solutions and the photostationary state is on the side of the E-isomer.
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  • 81
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    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 44-50 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Some aromatic compounds containing the imino group (NH) were nitrated in acetic acid or anhydride, and the ortho/para ratios were measured. N-Methyl derivatives of the aforementioned compounds are much less reactive when nitrated under comparable conditions and give significantly lower o/p ratios. These results along with the literature data support the hypothesis that the acetanilide-type compounds are nitrated via N-nitro intermediates.
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  • 82
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    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 51-56 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: On the Reaction of Dicyclopentadiene Diepoxide with Acrylic AcidThe esterification of dicyclopentadiene diepoxide as a bifunctional epoxide with acrylic acid was investigated. The influence of solvent polarity, reaction temperature and the catalytic system used are discussed. It was found, that the reaction rate increased with increasing solvent polarity. By using tertiary amines as catalysts, only a small catalytic effect was observed. On the contrary, a good catalytic effect was achieved with Lewis-acids. By means of FeCl3, a vinylester containing epoxide groups and C=C-double-bonds is obtained, which polymerizes via various mechanisms.
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  • 83
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    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 261-270 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new group of juvenoids with the 5,5-dimethylcyclohex-3-ene system was obtained by a multi-step synthesis starting from (+)-3-carene (1). Esters 15, 16 and 18 were synthesized by the Wadsworth-Emmons reaction of ketone 14 or aldehyde 17 with appropriate phosphonates. Esters 19 and 20 were obtained by the Claisen rearrangement of allylic alcohol 21 with trimethyl or triethyl orthoacetate. Juvenoids obtained were active against Dysdercus cingulatus and were inactive against Tenebrio molitor.
    Additional Material: 3 Ill.
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  • 84
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    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 271-283 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Investigations of the Synthesis and Properties of Amphiphilic PolymersBy reaction of propylene/maleic anhydride copolymers with the sodium salt of α-dodecyl-ω-hydroxy-trioxyethylene ionic polymers with different shares of long aliphatic side chains were prepared. The properties of these amphiphilic polymers were studied. Like micelles they are able to solubilize nonpolar probe molecules (N,N-dimethyl-aminoazobenzene). Viscosity measurements show the dependence of the conformation of the polymeric chain in solution on the share of aliphatic side chain and the degree of protonation. The polymers from micelle-like aggregates. It is supposed that the polymer with a high share of aliphatic side chains froms several local aggregates per polymer chain, while the polymer containing only few side chains seems to form intermolecular aggregates between different polymer chains. These investigations were performed with pyrene as probe molecule. Pyrene was also used to examine the micropolarity of the aggregates. Like polyelectrolytes the amiphilic polymers are able to cause the aggregation of opposite charged dyes (thionine).
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  • 85
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    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 293-298 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Tab.
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    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 305-308 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: HPLC Studies on the Distribution Behaviour of Selected I-Amino-3-aryl-guanidinium Nitrates
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  • 87
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    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 316-318 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis of Spirocyclic Orthoesters with Methacrylat Groups
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  • 88
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    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 323-324 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: About the Dialkylaminomethylation of N-Aryl-3,5-dimethyl-1,1-dioxo-1,2-thiazines
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  • 89
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    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 453-460 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Photochemistry of Acylazides. I. Photo- and Thermochemistry of 5-Azidocarbonyldibenz[b,f]azepine and its DimerThe reactions of the title compounds, two new carbamoylazides, by photoexcitation and in the ground state, respectively, were investigated. The photochemistry of compounds 1 und 2 differs from that of other heterocycles of the same type and is determined by the azido group. They exhibit the three known kinds of reactions of carbamoylazides via singlet and triplet nitrene, respectively, and the Curtius-rearrangement forming an intramolecular insertion product 6, dibenz-[b,f]azepine 4 and the isocyanate. Products from triplet nitrenes are lacking in the photoreaction of the dimeric azide 2.The decomposition of the azide 1 can be sensitized by triplet energy transfer. Surprisingly, the isocyanate is also formed by triplet sensitization.Photoexcited pyrene reacts with 1 via electron transfer yielding rearrangement and triplet products, respectively. In contrast to diphenylcarbamoylazide, the reaction pathway of the thermally excited compounds leads to nitrene products mainly.
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  • 90
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    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 476-478 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
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  • 91
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    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 484-486 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Tab.
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  • 92
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    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988) 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 93
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    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 521-529 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Monothiomalonamides (1a, b) coupled with arenediazonium salts yield the α-arylhydrazone derivatives (2a - c), Reaction of 1a, b with α-haloketones afforded polysubstituted thiazoles 6a - c. Compounds 6 condensed with p-nitrosodimethylaniline and coupled with arenediazonium salts yield the azomethine derivatives 7a - d and the arylhydrazones 8a - h, respectively.Compounds 1a, b behave differently towards hydrazonyl chlorides, they yielded arylazodimethylthiazoles 13a - c and thiazolylacetanilides 12a - c respectively.
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  • 94
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    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 621-625 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 4 Tab.
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    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
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  • 96
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 653-656 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and Conformation of Tricyclic Compounds with [6.3.2]Propellane and [6.1.6.2]Dispirane Structure
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 97
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
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  • 98
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 674-676 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis of o-Brombenzylphenylphosphine
    Type of Medium: Electronic Resource
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  • 99
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988) 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
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  • 100
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 683-694 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Nucleophilic Substitutions with Bischloronitroso Compounds. IV. Sulfonylaminooximes as Extracting Agents for Copper(II)New vicinal sulfonylaminooximes 5a-5v are synthesized from bischloronitroso compounds 1 or 2-chlorooximes 2 and sulfonamides 4 under alkaline conditions. In several cases oligomeric products 6 result instead of 5. 2-Sulfonylaminobenzophenoneoximes 8a-g are also prepared from 2-aminobenzophenones and sulfonyl chlorides and subsequent reaction with hydroxylamine. The pH0,5 values for the extraction of copper-(II)-ions into a chloroformic solution are between 2,8 and 4. Compounds 8 are comparably weaker extragents then oximes 5.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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