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  • Inorganic Chemistry  (83,665)
  • Nuclear reactions  (4,460)
  • 201
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1129-1133 
    ISSN: 0009-2940
    Keywords: Vanadium ; S Ligands ; Schiff bases ; N ligands ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The tetradentate, neutral disulfide [bis(thioether)] ligand 1,6-bis(o-pyridyl)-2,4-dithiahexane, NSSN, reacts with [VCI2(tmeda)2] to form the octahedral (all-cis; C2v-symmetric) complex [VCl2(NSSN)] 1, the first low-valent vanadium complex in which the thio functions are exclusively organic sulfides. Treatment of (VOCl2(thf)2] with O-mercaptoaniline, followed by reaction with o-hydroxynaphthaldehyde yields the non-oxo V′” complex [V(S′N′O)2] 2, derived from the Schiff base HS′N′OH, where 0 and S′ are phenolate and thiophenolate functions, respectively, and N′ is the Schiff base (enamine) nitrogen. Complex 2, with the ligands in a distorted trigonal-antiprismatic array, is a rare example of a structurally characterized complex where the Schiff base is preserved at the expense of its thiazoline tautomeric form.
    Additional Material: 3 Ill.
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  • 202
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997) 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 203
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1193-1195 
    ISSN: 0009-2940
    Keywords: Stilbene ; 4.4′-Diarylstilbenes ; Palladium ; Pd-catalyzed ; C-C coupling ; Dyes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The palladium-catalyzed coupling of ethene with 4-bromobiphenyl and 4′-bromo-4-biphenylsulfonic acid permits a facile one-pot preparation of the laser dyes (E)-4,4′-diphenylstilbene (BPS, 3) and bis(triethylammonium) (E)-4,4′diphenylstilbene-4″,4″-disulfonate (6) in diastereomerically pure form on a multigram scale, with yields of 69 and 64%, repectively. The latter can easily be transformed to its dipotassium salt 7, the Stilbene I dye.
    Additional Material: 1 Tab.
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  • 204
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1189-1192 
    ISSN: 0009-2940
    Keywords: Tellurium ; Bismuth ; Tetratellurium(2+) ; Halogenobismutates(III) ; Crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of Te, TeX4 and BiX3 [X = Cl, Br] in sealed, evacuated glass ampoules in the temperature range 170° 100°C yields a variety of compounds composed of tellurium polycations and halobismutate anions. Two of these have been identified by crystal structure analyses as Te4[Bi6Cl20] (triclinic, P., a = 738.8(2), b = 875.1(2), c = 1389.1(6) pm, α = 87.89(2), β = 82.87(4), γ = 87.89(2) ·, Z = 1) and Te4[Bi2Nr8 (triclinic, P., a = 726.0(4), b = 773.7(4), c = 901.8(5) pm, α = 92.95(2), β = 102.23(2), γ = 92.87(2)., Z = 1). Both compounds were obtained as black crystals with a violet lustre and contain square-planar Te42+ cations. Te4[Bi6Cl20] contains a two-dimensional polymeric anion [Bi6Cl20]2- made up of corner- and edge-sharing BiCl6 octahedra with attached BiCl3 groups. The Bi-Cl distances vary over a very wide range from 245 to 334 pm. Te4[Bi2Br8] consists of a onedimensional chain [BiBr2Br4/2-[n of cis-edge-connected BiBr6 octahedra with Bi-Br distances ranging from 264 to 318 pm.
    Additional Material: 2 Tab.
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  • 205
    ISSN: 0009-2940
    Keywords: Acyllithium equivalents ; Lithium ; Carbenes ; Structure elucidation ; Ab initio calculations ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 3-Lithiated 4-tert-butyl-imidazol-2-ylidene, 3-lithiated 4-tert-butyl-thiazol-2-ylidene, and the ZnBr species of the latter, are shown to be stable carbenes by X-ray crystal structure determination. The crystal data are confirmed by 13C-NMR investigations in solution and quantum-chemical calculations. The exceptional stability of the acyl anion equivalents is due to the p(.) stabilization of the carbene carbon atoms by the adjacent amino (thio) substituents, as is also the case in the structurally related stable carbenes, which have recently been isolated for the first time by A. J.Arduengo III et al., and in stable nitrenium ions, as found by our group.
    Additional Material: 5 Ill.
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  • 206
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    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1235-1240 
    ISSN: 0009-2940
    Keywords: Phosphorus ; Phase transitions ; Molecular crystal ; Crystal growth ; Low-temperature crystal structure ; Librational motion ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: White phosphorus occurs in three modifications. The α form, which exists at roomtemperature, transforms reversibly to the β form at -77°C. The α · β transformation may be strongly delayed. Quenching the α form to -185°C followed by slow warming results in an exothermic reactions with formation of the γ form which transforms into the β form at -120°C in an endothermic reaction. A transition β · γ is not observed. The γ form is characterized by its powder diagram. The structure of the β form is redetermined from a single crystal at -185°C (P., α = 547.88(5), b = 1078.62(11), c = 1096.16(11)pm, α= 94.285(8), β = 99.695(7), γ = 100.680(7)., V = 623.79(10) · 106 pm3, Z = 6 formula units per cell). The P4 molecules exhibit pronounced librational motion in spite of the low temperature of investigation. The arrangement of the centers of the tetrahedra corresponds to the atom positions in the γ-plutonium structure, which is discussed in relation to the bcc structure.
    Additional Material: 7 Ill.
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  • 207
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1269-1272 
    ISSN: 0009-2940
    Keywords: Indium ; Clusters ; Low-valent compounds ; Trapping reactions ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The tetrahedral cluster compound tetrakis[[Tris(trimethylsilyl)methyl]indium(I)] 91) reacts in boiling n-hexane with benzil derivatives (p-X-C6H4)C(O)(p-X-C6H4) (X = H, OMe, Br), to yield the 1,4-cycloadditon products of the monomeric alkylindium(I), In-C(SiMe3)3, in which the In atoms are coordinated by a chelating enediolato ligand, to form a five-membered InO2C2 heterocycle. As shown by two crystal structure determinations (X = H, OMe), the products are dimeric in the solid state, with a four-membered In2O2 heterocycle in the molecular center and both C(SiMe3)3 groups, as well as both enediolato substitutents in a cis arrangement.
    Additional Material: 2 Ill.
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  • 208
    ISSN: 0009-2940
    Keywords: P ligands ; P-P bond formation reaction ; Molybdenum ; Chromium ; Nickel ; Carbonyl complexes ; Main group elements ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: [Cr(CO)5PCl3] reacts with different metallates K[CpxMo(CO)3] [Cpx = ·5-C5H4tBu (Cp]), ·5-C5H3tBu2-1,3 (Cp))], K[CpFe(CO)2], K[Cp]Cr(CO)3], K[C}*Ni(CO)] and Na2[Cr2(CO)10] at -78°C in THF to yiel various P2, cyclo- P3 and cyclo-P5 ligand complexes of the formulae [Cp] Mo(CO)2 (.2-P3)] (1a), [Cp]Mo(CO)2(.3-P3)] (1b), [{CP'Mo-(CO)2}2(μ,.2-P2)] (2a), [{Cp]Mo(CO)2}2(μ, ·2-P2)] (2b), [Cp]Fe).5-P5)] (3), [(Cp'Cr)2(μ,.5-P5)] (4), [{Cp]Cr(CO)2}2-(μ,.2-P2)] (5), [(Cp*Ni)2(μ,.2-P2){Cr(CO)5}2] (6). [{(CO)5Cr}Cl2PPCl2{Cr(CO)5}] (7) and [{Cr(CO)5}2PCl (8). Comprehensive studies of the reaction pathway leading to formation of the cyclo-P3 product 1a give strong indications that a sequence involving metal-halogen exchange and stepwise P-P bond formation takes place, proceeding via [{CO}5Cr}Cl2PPCl2{Cr(CO)5}] (7) and the cyclo-P3 precursor compond [{Cp]Mo(CO)3}{Cp'Mo(CO)2}2{Cr(CO)5}(μ,.3:1:1-P3)] (9). The latter two complexes have been isolated and structurally characterized.
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  • 209
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    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1321-1325 
    ISSN: 0009-2940
    Keywords: Arene Complexes ; Ruthenium ; Diastereoselective ; Reduction ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two preparative routes are reported that give access to the racemic series of planar chiral [(arene)(COD)Ru] derivatives containing η6-bonded o-tolyl ketone or aldehyde arene units. The ketone and aldehyde functions of these have subsequently been reduced by nBuLi and PhLi, respectively. Hydrolysis converts the initially formed lithium salts into diastereomeric benzyl alcohol complexes lithium salts into diastereomeric benzyl alcohol complexes in high yields. The formation of the new stereogenic centre is diastereoselective (88% de) for the aldehyde and diastereospecific for the ketone (de 〉 99%). Due to a sterically overcrowded situation, the rotation of the chiral side chain of [(COD) (η6-o-tolyl-tert-butylphenylmethanol) Ru] (7) is hindered, as is the rotation of the phenyl and tert-butyl substituents. As a consequence, the hydroxyl group is fixed at a position close to the metal both in solution and in the solid state.
    Additional Material: 1 Ill.
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  • 210
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    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1349-1352 
    ISSN: 0009-2940
    Keywords: Heterocycles ; 1,1-Organoboration ; Disilanes ; 1- Alkynylsilanes ; NMR spectroscopy ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1,2-Di-1-propynyl-tetramethyldisilan (1) reacts with triorganoboranes R3B [R = Et (2a), CH2Ph (2c), 2-thienyl (2d)], 9-ethyl-9-borabicyclo[3.3.1]nonane (3), and diethyl(N-pyrrolyl)borane (4) by twofold 1,1-organoboration to give selectively the respective organo-substituted 1,2-dihydro-1,2,5-disilaborepines 5a-d,6, and 7 in high yields. The compounds 5-7 were characterized by 1H-, 11B-, 13C-, and 29Si-NMR spectroscopy in solution. The molecular structures of the distance 1 and of the heterocycle 5c were determined by X-ray structure analysis.
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  • 211
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    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1361-1363 
    ISSN: 0009-2940
    Keywords: Titanium ; Lead ; Alkoxides ; Amides ; Mixed-Metal species ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction between Ti(OiPr)4 and [Pb(NtBu)2] (1) in refluxing THF afforded the complex Ti(OiPr)4OPb4(NtBu)3] (2) which has been characterized by X-ray diffraction studies and by 1H- and 13C-NMR spectroscopy. Titanium is five coordinate and it displays a trigonal bipyramidal stereochemistry with the pb4(tBuN)3O cage ligand bonded to titanium through the oxygen atom and occupying an apical position. The origin of the cubane lead ligand is discussed.
    Additional Material: 1 Ill.
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  • 212
    ISSN: 0009-2940
    Keywords: Tripod ligands ; Phosphane oxides ; Cobalt ; Oxidation ; Catalysis ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reactivity of complexes of triphos [CH3C(CH2PPh2)3] and CoCl2 towards dioxygen has been investigated. Reaction of the pseudo-tetrahedral complex (η2-triphos)CoCl2 (1) with dioxygen yields after work-up the mixed phosphane/phosphane oxide ligands triphosO and triphosO2. The novel ligand triphosO2 can be obtained in quantitative yield using catalytic amounts of 1. In order to gain some insight into the catalytic dioxygen activation reaction, experiments with various triphos/Co/Cl species, in different solvents and at several concentrations have been carried out. A mechanism involving two separate reaction pathways is proposed. Complexes of triphosO and triphosO2 with CoCl2, [η2-(P, P)-triphosO]CoCl2 (4), and [η2-(P, O)-triphosO2]CoCl2 (5), which are present as intermediates in the oxygenation reaction, have been isolated and fully characterized including X-ray structural analyses.
    Additional Material: 7 Ill.
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  • 213
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    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1417-1422 
    ISSN: 0009-2940
    Keywords: Gold ; N ligands ; Gold(I) complexes ; (Imine)gold(I) complexes ; Guanidines ; Ketimines ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: (Tetramethylguanidine)gold(I) chloride (1) and bromide (2) are readily prepared in high yield from (Me2N)2C=NH and [AuCl(Me2S)] or [AuBr(tht) (tht = tetrahydrothiophene), repectively. NMR spectra of chloroform solutions of the two products indicate equilibria of the type 2 LAuX = L2Au+AuX2-. The cationic complex [Au(NH=C(NMe2)2)(PPh3)]+ is obtained as the triflate salt 3 from tetramethylguanidine and [Au(PPh3)]+O3SCF3-. In solution at low temperature (-60°C), this compound adopts a rigid structure whereby the NMe2 groups are rendered non-equivalent, but at ambient temperature there is coalescence of the NMe2 signals in the 1H- and 13C-NMR spectra. The related benzophenoneimine complex [Au{NH=CPh2}(PPh3)]+BF4- (4), which was synthesized as a reference3 compound, exhibits similar behaviour. In solution at low temperature (-60°C) the two phenyl rings of the ligand are diastereotopic. In contrast, the triisopropylphosphane derivative [Au[NH=CPh2](PiPr3)]+BF4- (5) is rigid on the NMR time scale, even at 25°C. Thbe solid-state structures of 2, 3, 4, and 5 have been determined by single-crystal X-ray diffraction. Compound 2 crystallizes in the ionic form with discrete Au … Au bonded ion pairs [Au[NH=C(NMe2)2]2]+ [AuBr2]- [Au … Au 3.1413(8) Å]. The cations of 3, 4, and 5 show the [Au(PPh3)]+ units N-coordinated to the imino groups, with the nitrogen atoms in a trigonal-planar configuration.
    Additional Material: 4 Ill.
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  • 214
    ISSN: 0009-2940
    Keywords: Selenium ; Fluorine ; Amides ; Cleavage reactions ; Cycloadditions ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Bis(trifluoromethylketiminoalkyl)diselanes [SeC(=NR)CF3]2 (6) [R = Me (a), iPr (b), tBu (c)] have been prepared in high yields (55-70%) by reaction of the diselane (SeC2F5)2 (2) with RNH2. However, the analogous reaction of 2 with secondary amines, R2NH, results in the cleavage of the Se-Se bond and leads to the N,N-dialkyl-2,2,2-trifluoroselenoacetamides Se=C(NR2)CF3 (7) [R = Me (a), iPr (b)]. Cleavage of 6a-6c with Me3SnH affords the selenoamides Se=C(NHR)CF3 (9) and the corresponding stannylselanes Me3SnSeC(=NR)CF3 (10) [R = Me(a), iPr (b), tBu (c)]. Selenoamides 7 and 9 can also be prepared from pentafluoroethylselenol HSeC2F5 (3), Se=C(F)CF3, (1) or its polymer [SeC(F)CF3]n (4) and primary or secondary amines. N,N-dialkyl-2-methyl-3-fluoro-4,4,4-trifluoroselenoacrylamides Se=C(NR2)C(Me)=C(F)CF3[R = Et (13a), iPr (13b)] are prepared in moderate yields under mild conditions by treating either trifluoromethylselenocarbonyl fluoride (1) or its polymer [SeC(F)CF3]n with 1-dialkylamino-1-propynes. The reaction proceeds by [2 + 2] cycloaddition and stereospecific electrocyclic ring-opening, yielding, with respect to the resulting C=C double bond, the E isomer as the only product. The molecular structures of 7b, 9a and 13b show the typical features of selenoamides with C(Se)-N bond shortening and C-Se bond elongation due to π interaction of the N lone pair with the C=Se double bond. The observed perpendicular orientation of the selenoamide and the alkene units of 13b prevents π delocalization.
    Additional Material: 4 Ill.
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  • 215
    ISSN: 0009-2940
    Keywords: Boron ; Phosphorus ; Spiro compounds ; Cage compounds ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactions of 1-lithio · DME-2,4-bis(dialkylamino)-l,3,2,4-diphosphadiboretanes (1a, 1b) with SiCl4 followed by dehydrohalogenation with tBuLi produce spirocyclic compounds [(R2NB)2P2]2Si (2a, 2b). The compounds have been characterized by spectroscopic methods and X-ray crystallography. The assembly process has also been followed and one intermediate species [(iPr2NB)2P2][(iPr2NB)P(H)(iPr2NB)P]SiCl (3) has been isolated and fully characterized.
    Additional Material: 4 Ill.
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  • 216
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    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1197-1200 
    ISSN: 0009-2940
    Keywords: Binuclear complexes ; Manganese ; Napthalene complexes ; Dienyl complexes ; Alkynes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Pentacarbonyl(μ-.4:6-1,4-dimethylnapthalene)dimanganese-(Mn-Mn) (1), upon UV irradiation at 193 K in the presence of 2-butyne (2), yields tetracarbonyl(μ-.2:2-2-butyne)(μ-1,2,3,4-.:1,4,4a,8a-.-1,4-dimethylnaphthalene)dimanganese (3) and tricarbonyl(4a,6,7,8,8a-.-5-hydro-1,4-dimethylnapthalene)-manganese (4). The tetracarbonyl complex 3 rearranges in solution at room temperature to give tetracarbonyl(μ-.2:2-2-butyne)(μ-4a,5,8,8a-.:5,6,7,8-.-1,4-dimethylnaphthalene)-dimanganese (5). The complexes 3 and 5 were characterised by IR and NMR spectroscopy, and by mass spectrometry, and complex 4 by IR and NMR spectroscopy. The molecular structures of 3 and 4 were determined by single-crystal X-ray diffraction analyses.
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  • 217
    ISSN: 0009-2940
    Keywords: 2-Li(ZnCl)-substituted oxazoles (thiazoles, imidazoles) ; Acyclic isomers ; NMR spectroscopy ; Lithium ; Zinc ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 2-Metallated oxazoles, thiazoles and imidazoles are of interest for the preparation of derivatives of the respective heterocycles, and - especially in the case of metallated thiazoles - as acyllithium equivalents in organic syntheses. Metallation at C2 of these compounds, however, often leads (more so with Li-oxazoles than with Li-thiazoles and Li-imidazoles) to products derived from the acyclic isomers of the metallated heterocycles. In order to obtain more information on the positions of the relevant equilibria, we have carried out a 13C-NMR study of substituted li- and ZnCl-oxazoles, Li-thiazoles and Li-imidazoles. In the case of Li-oxazoles, the equilibrium is completely on the side of the acyclic isomers. Addition of ZnCl2, however, leads to ring-closure, and, even in the case of 2-ZnCl-substituted benzoxazole, only the ring-closed isomer is observed. This demonstrates a dramatic gegenion effect on the equilibrium between two isomeric anions. In the case of Li-thiazoles, depending on the substitution pattern, either solely the ring-closed or an equilibrium with the ringopened isomer is observed. In the series of Li-imidazoles, only the 2-lithiated benzimidazole is in equilibrium with its ring-opened isomer. The tendency of these compounds to undergo ring-opening parallels the leaving group properties of the various subunits [OLi 〉 SLi 〉 R2NLi, and phenyl-O(S, NR)Li 〉 vinyl-O(S, NR)Li]. The difference between the effects of Li+ vs. ZnCl+ in the (benz)oxazole series is in agreement with results of solid-state structure investigations of 2-lithiated and a 2-zincated thiazole: in the Li compound the C-S bond is 2.9 pm longer than in the ZnCl species, indicating a more facile C-S bond cleavage with Li+ as the gegenion.
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  • 218
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    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997) 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 219
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1013-1020 
    ISSN: 0009-2940
    Keywords: Donor-acceptor complexes ; Silylene ; Germylene ; Stannylene ; Ab initio calculations ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The complexes of various donor molecules, AH3 (A = N, P, As, Sb, Bi) and AH2 (A = 0, S, Se, Te) with silylene, germylene, and stannylene (1Al ground state) were studied by means of quantum chemical investigations at ab initio level utilizing all valence electron basis sets and relativistic corrected effective core potential methods. Accordingly, the donor molecules are weakly bound, the association energies are in the range of 15-30 kcal per mole. The exothermic energies for adduct formation, i.e., the resulting binding energies for the donor complexes, decrease in the order silylene 〉 germylene 〉 stannylene. The population analysis indicates for NH3 and BiH3 only a weak bonding towards the XH2 fragment (X =Si, Ge, Sn) while the higher homologues (A = P, As, Sb) form ylide structures, 1.2-dipolaric in nature. The addition of two donor molecules has been studied for silylene and is much less favourable than donor mono-addition. For the donor mono-addition a dual parameter relationship between (a) the HOMO energies of the donor (n-orbital of the AH3 unit, n, p-orbitals for AH2) and (b) the covalent bond energies (from the literature) versus the binding energies of the donor-acceptor compounds was examined. This dual parameter equation describes satisfactorily the essential features of the stabilities of the donor-acceptor structures.
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  • 220
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1043-1046 
    ISSN: 0009-2940
    Keywords: Matrix isolation ; Ab initio calculations ; Oligosilanes ; Silicon atoms ; Reaction mechanisms ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Pulsed flash pyrolysis of 1,1,l-trimethyltetrasilane (5) led to trimethylsilane, silane and a further species which is believed to be dibridged Si2H2 (13). Another route to 13 was found in the cocondensation of hydrogen and silicon atoms in an argon matrix at 12 K. The identification of matrix-isolated 13 is based on observed IR bands at 1475.6, 1092.8 and 890.3 cm-1. These positions are in good agreement with the ab initio calculated wavenumbers for the strongest absorptions of 13. The band shifts for the mono- and dideuterated isotopomers support this assignment.
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  • 221
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1063-1067 
    ISSN: 0009-2940
    Keywords: Heterobimetallic complex ; Carbene complexes ; Bridging ligands ; Coupling reaction ; Alkynes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Sequential reaction of the dimethylamino(ethynyl)carbene complex [(CO)5 W=C(NMe2)C≡CH] (1) with nBuLi, CuI and BrC≡CSiMe3 affords the dimethylamino(trimethylsilylbutadiynyl)carbene [(CO)5W=C(NMe2)C≡C—C≡C—SiMe3] (2). Desilylation of 2 with KF/THF/MeOH gives [(CO)5W=C(NMe2)C≡C—C≡CH] (3). The C-stannylated carbene complex [(CO)5W=C(NMe2)C≡C—C≡CSnBu3] (4) is obtained by deprotonation of 3 with nBuLi and subsequent reaction with Bu3SnCl. Pd-catalyzed coupling of complex 4 with [ClRu(CO),Cp] affords the heterobimetallic pentadiynylidene complex [(CO)5W=C(NMe,)C≡C—C≡CRu-(CO)2Cp] (5) The analogous Fe derivative [(CO),W=C(NMe,)C≡C—C≡CFe(CO)2Cp] (6) is obtained by sequential reaction of 3 with nBuLi and [IFe(CO)2Cp] Similarly, treatment of 3 first with nBuLi and then with half an equivalent of HgCl2 affords the novel C4HgC4-bridged biscarbene complex [(CO)3W=C(NMe2)C≡C—C≡CHgC≡C—C≡CC(NMe2)=W(CO)5]( 7 ) All new compounds are stable at room temperature. Spectroscopic data suggest weak interaction of the metal centers in 5 - 7.
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  • 222
    ISSN: 0009-2940
    Keywords: Mass spectrometry ; Peroxides ; Oxenoids ; Density functional theory ; Kinetic energy release ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A combined mass-spectrometric and theoretical approach has been used for an investigation of the gas-phase chemistry of two representative alkylperoxy anions. Metastable CH3OO- ions undergo unimolecular loss of molecular hydrogen and formaldehyde yielding HCO-2 and OH-, respectively. The observed reactivity is in pleasing agreement with calculations of the [C,H3,O2- and [C,H,O2]- potential-energy surfaces at the BECKE3LYP/6-311+ + G** level of theory. Upon exhaustive methylation of the α-position as in t-C4H9OO- anions, the reactivity switches completely to an elimination of (CH3)2C=CH2 giving rise to the formation of HOO-. The results obtained for the “bare” alkylperoxy anions are used for the analysis of the EI mass spectrum of (t-C4H9OOLi)12 dodecamers, which thermally decompose in the inlet system at a probe temperature of ca. 130°C. The decomposition is rationalized by a mechanism involving nucleophilic attack of one t-C4H9OOLi subunit on the oxenoid oxygen atom of a second t-C4H9OOOLi moiety. This reaction may produce t-C4H9OOOLi trioxy species as intermediates, which rapidly decompose to singlet dioxygen and t-C4H9OLi.
    Additional Material: 4 Tab.
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  • 223
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1777-1785 
    ISSN: 0009-2940
    Keywords: Lithiation ; Aminomethylation ; Nitrogen heterocycles ; Diazasilaheterocycles ; Diazaphosphaheterocycles ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The aminals tetramethylmethylenediamine (TMMDA) la, dicyclohexyldimethylmethylenediamine (CMMDA) lb, and di-isopropyldimethylmethylenediamine (IMMDA) lc are doubly metalated by LitBu to give LiCH2N(R)CH2N(R)CH2Li [2a: R = Me, 2b: R = Cy (Cy = cyclohexyl), 2c: R = iPr], which precipitate out of pentane as highly pyrophoric substances. Deuteration confirms N-methyl metalation exclusively. A series of aminomethylation reactions were performed by means of the doubly lithiated aminals 2a-c. The reactions of 2a-c with monochlorosilanes yield the silylated species R′3SiCH2MN(R)CH2N(R)CH2SiR′3 (3a: R′= Me, R == Me; 3b: R′ == Me, R == Cy; 3c: R′= Me, R = iPr 4: R′= Ph, R = Me, see Scheme 2). The use of dichlorosilanes lead to six-membered heterocycles 6a-6d. 6a is transferred into a mono quarternary ammonium salt 7 by methylation with MeI. The spirocycle 8 is obtained from SiCl4 and two equivalents of 2a. Similarly, several substituted 1,3-diaza-5-phosphacyclohexanes 9a-e (R1 = Me, Ph, NPh2, NCy2, see Scheme 3) are synthesized by the reaction of dichlorophosphanes R1PC2, with 2a and 2b, respectively. Oxidation of 9d with sulfur yields 12a, which is characterized by X-ray structure determination.
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  • 224
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1807-1811 
    ISSN: 0009-2940
    Keywords: Alkynes ; Photoelectronspectroscopy ; Electronic structure ; X-ray investigation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The structures of 6-isopropylidene-1,1-dimethyl-1-silacyclodeca-3,8-diyne (2), 1,6-dimethyl-1,6-disilabicyclo[4.4.4]tetradeca-3,8,12-tryine (4), and 1,1,2,2,3,3-hexamethyl-1,2,3-trisilacyclodeca-4,9-diyne (6) have been investigated by means of X-ray crystallography. In 2 and 6 a chair conformation is adopted in the solid solid state. In 4 the three butyne groups are twisted around the Si—Si axis against one another. The torsion along the triple bond axis (Si-CH2-CH2,/Si) amounts to 29.0(1). The He(I) photoelectron (PE) spectra of 2 and 6 together with those of 1,1-dimethyl-1-silacyclodeca-3,8-diyne (1), 1,1,6,6-tetramethyl-1,6-disilacyclodeca-3,8-diyne (3),1,12,2,3,3-hexamethyl-1,2,3-trisilacycloundeca-4,10-diyne (7) have also been recorded. The PE spectra were interpreted on the basis of results from SCF MO calculations (3-21G*). They reveal a smaller splitting of the π-bands in 1-3 as compared to cyclodeca-1,6-diyne. In the PE spectra of 5-7 we encountered a strong interaction between the silicon chain and the in-plane π-orbitals.
    Additional Material: 3 Ill.
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  • 225
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 209-215 
    ISSN: 0009-2940
    Keywords: Titanium ; Amidocyclopentadienyl ligand ; Alkyltitanium compounds ; Lewis acids ; Agostic interactions ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Titanium complexes of the general type Ti(η5:η1-C5H4Si-Me2NCH2C6H3X2-2,5)Cl2 (X=H, F), containing a linked benzylamido-cyclopentadienyl ligand, were prepared by reaction of Ti(η5-C5H4SiMe2Cl)Cl3 with lithium amide Li(NHCH2C6H3X2-2,5). A single-crystal X-ray structural analysis of Ti(η5: η1-C5H4SiME2NCH2C6H3F2-2,5)Cl2 revealed a conformation in the solid state in which the aryl ring is turned away from the metal center. Ti(η5:η1-C5H4SiMe2NCH2C6H5)Cl2 can be alkylated with a variety of reagents to form extremely sensitive complexes of the type Ti(η5-C5H4SiMe,2NCH2C6H5)R2 (R=Me, CH2 C6H5, CH2SiME3, CH2CMe2C6H5). Reaction of Li2[C5Me4SiMe2NCH2C6H5] with TiCl3(THF)3 gave Ti(η5: η1-C5Me4SiMe2NCH2C6H5)Cl2, which can also be alkylated to form dialkyl complexes of the type Ti(η5:η1-C5Me4SiMe2NCH2C6H5)R2(R=Me, CH2C6H5, CH2SiMe3, C6H5).A single-crystal X-ray structural analysis of Ti(η5:η1-C5Me4SiMe2NCH2C6H5)(CH2C6H5)2 suggests the presence of α-agostic bonding of one of the titanium-bound CH2C6H5 groups to the titanium center.
    Additional Material: 3 Ill.
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  • 226
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 231-234 
    ISSN: 0009-2940
    Keywords: Diasteroselective cyclopropanation ; Copper compounds ; Homogeneous catalysis ; Molecular recognition ; Bimacrocycles ; Alkenes ; Macrocyclic ligands ; Heterocycles ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Concave 1,10-phenanthrolines 1a-c have been used as ligands in the copper(I)-catalyzed cyclopropanation of alkenes 2 with ethyl diazoacetate. The complexes proved to be efficient cyclopropanation catalysts and exhibited an enhanced diastereoselectivity, particularly in the reactions of cyclic alkenes 2b-d. The preferred formation of exo-cyclopropanes 3b-d can be explained by the concave shape of these catalysts.
    Additional Material: 1 Ill.
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  • 227
    ISSN: 0009-2940
    Keywords: Polycycles ; Hydrocarbons ; Palladium catalysis ; Domino processes ; Cross coupling ; Homogeneous catalysis ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Vinylic bromides of type 1 undergo cross-coupling reactions with diphenylacetylene (5) leading to various polycyclic hydrocarbons. The ratio of the 1:1 to the 1:2 products can readily be controlled by varying the reaction conditions.
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  • 228
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 291-294 
    ISSN: 0009-2940
    Keywords: Halogenoacetates ; Silver salts ; Solid-state reactions ; Polymerization ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The structure of silver chloroacetate was determined by single-crystal X-ray structure analysis. This represents the first salt of a monohalogenoacetic acid with a monovalent metal whose structure was determined with high precision. The salt undergoes a thermally induced solid-state polymerization to polyglycolide under elimination of silver chloride. A probable mechanism for a structure-determined reaction in the solid state is discussed.
    Additional Material: 4 Ill.
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  • 229
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    Keywords: Methyl trifluoropyruvate ; Tris(trimethylsilyl) phosphite ; Methyl 2-[bis(trimethylsiloxy)phosphoryl]-3,3,3- trifluoro-2-(trimethylsiloxy)propionate ; Bis(trimethylsilyl) [(2,2-difluoro-l-trimethylsiloxy)ethenyl]- phosphonate ; Solid-state structures ; Fluorine ; Phosphorus ; Silicon ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Methyl trifluoropyruvate (1) and tris(trimethylsilyl) phosphite (3) reacted to give methyl 2-[bis(trimethylsiloxy)phosphoryl]- 3,3,3-trifluoro-2-(trimethylsiloxy) propionate (4). Partial hydrolysis furnished propionate 6, the molecular structure of which was obtained in the solid state. Attempted trimethylsilylation of the methylcarboxylato group in 4 using iodotrimethylsilane caused the formation of bis(trimethylsily1) [(2,2- difluoro- 1 -trimethylsiloxy)ethenyl]phosphonate (8). For comparison, methyl pyruvate (2) and 3 gave methyl 2-[bis(trimethylsiloxy)phosphoryl]-2-(trimethylsiloxy)propionate (5).
    Additional Material: 1 Ill.
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  • 230
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 307-316 
    ISSN: 0009-2940
    Keywords: Halogen oxides ; Solid-state structures ; Intermolecular interactions ; Halogens ; Oxygen ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The development of new preparative and analytical techniques that allow appropriate handling and characterizations of the capricious halogen oxides have initiated a revival of their chemistry. Due to these recent activities, the amount of well-confirmed knowledge about such oxides has considerably increased. This is especially valid for the structural chemistry in the solid state, which (among other topics) has greatly benefitted from developments in the techniques of in situ crystal growth of low melting substances on a diffractometer. As a consequence, some general crystal chemical features have become apparent: The coordination polyhedra of the halogen oxides can be readily understood in terms of the qualitative VSEPR concept, and there is a pronounced tendency to form mixed valence compounds where the respective valence states can be easily deduced from the coordination polyhedra. Furthermore, intermolecular or interionic bonds are significant, with increasing importance when moving from chlorine to iodine. Finally, ClO2 appears to be the only representative with the halogen in an even oxidation state.
    Additional Material: 11 Ill.
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  • 231
    ISSN: 0009-2940
    Keywords: Cavitand ; Electrochemistry ; Iron sulfur cluster ; Metalloprotein model ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: NMR and Mössbauer spectroscopy show that a novel tetrathiol ligand, based on the cavitand diphenylglycoluril, encapsulates a 4Fe-4S cluster and induces asymmetry in it. The cluster gives a weak electrochemical current response in DMF, with a half-wave potential for the 2-/3- reduction vs. Fc+/Fc of -1.7 V. Ba2+ ions are adsorbed, according to X-ray analysis of the SEM image of the electrode, and act as modulator and promoter of the electrochemical response. On the basis of cyclic voltammograms it is proposed that this adsorption creates electroactive sites, changing the type of diffusion controlling the mass transport to the electrode from radial to linear, and that it helps the negatively charged complex, which contains a dipole, to approach the negative electrode in an orientation favourable for electron exchange. This feature makes the complex an important model for ferredoxins, in spite of a difference in redox potential.
    Additional Material: 10 Ill.
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  • 232
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 63-67 
    ISSN: 0009-2940
    Keywords: Barium ; Copper ; Arsenate ; Magnetic susceptibility ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two new compounds Cu4(AsO4)2O (1) and Ba2Cu7As6O24 (2) were obtained from a mixture of CuO and As2O5 · xH2O heated to 1090°C for 72 h in a BaCO3 flux. Compound 1 was obtained as dark green crystals, belonging to the orthorhombic crystal system. Compound 2 was obtained as light gray to colorless crystals belonging to the triclinic crystal system. The structure of 1 contains two copper ions with distorted trigonal bipyramidal geometries and a third with a distorted square pyramidal geometry. One ‚oxide‘ ion is surrounded by four copper ions in a distorted tetrahedral arrangement. Compounds 2 consists of two chains with alternating units of trigonal bipyramidal CuO5 and square planar CuO4 units, with the oxygen atoms derived from the AsO4 groups. Magnetic susceptibility measurements of 1 and 2 both show effective magnetic moments, μeff=1.90-1.95 B.M./Cu at 25°C, which is consistent with Cu2+ ions having one unpaired electron. Significant antiferromagnetic coupling was revealed by variable temperature measurements. At very low temperatures (15-25 K) samples of both 1 and 2 undergo a transition to a weak ferromagnetic state.
    Additional Material: 6 Ill.
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  • 233
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 77-82 
    ISSN: 0009-2940
    Keywords: Monoterpenes ; Sesquiterpenes ; Stereoselectivity ; Alk-l-enyllithium(sodium) Metal exchange, halogen vs. hydrogen ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: (Z)-(3,3-Dimethylbicyclo[2.2.1]hept-2-ylidene)methyllithium can be readily generated by treatment of (Z)-3-bromomethylene-2,2-dimethylbicyclo[2.2.1]heptane with tert-butyl-lithium. At -75°C, the organometallic intermediate is configurationally stable and reacts with a variety of electrophiles under stereochemical retention.
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  • 234
    ISSN: 0009-2940
    Keywords: Zinc complexes ; Alkyl carbonate complexes ; CO2 fixation, reversible ; Catalysis ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The zinc hydroxide complexes Tp*Zn-OH with TpCum,Me = tris(3-cumenyl-5-methylpyrazolyl)borate and TptBu,Me = tris(3-tert-butyl-5-methylpyrazolyl)borate can be converted to the alkyl carbonate complexes Tp*Zn-OCOOR by reaction with dialkyl dicarbonates or with alcohol and CO2. An alternative formation reaction is the treatment of the pyrazolyl borate with zinc perchlorate and potassium carbonate in alcohol. The interconversion between TpCum,MeZn-OH and TpCum,MeZn-OCOOMe in methanol-containing solution can be repeatedly performed in both directions by bubbling either CO2 or N2 through the solution. The alkyl carbonate complexes show a variable sensitivity towards hydrolytic destruction with reformation of the hydroxide complexes. The complexes TptBu,MeZn-OCOOR (R = Me, Et) release CO2 under high vacuum to form the alkoxide complexes TptBu,Me-Zn-OR, which could not be obtained pure due to their extreme water sensitivity. Indirect evidence for their existence is also obtained by the reaction between TpCum,MeZn-OCOOMe and methyl iodide, forming TpCum,MeZn-I and dimethyl ether. The Zinc hydroxide complexes catalyse the formation of diethyl carbonate from ethanol and CO2.
    Additional Material: 1 Tab.
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  • 235
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 119-122 
    ISSN: 0009-2940
    Keywords: Selenolate ; Aminoselenolate ; Lithium compound i Ab initio calculations ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Lithium 2,2,6,6-tetramethylpiperidide inserts elemental selenium into its Li-N bond with the formation of lithium 2,2,6,6-tetramethylpiperidinoselenolate 1. In the crystal 1 is an unsymmetric dimer. One lithium atom is coordinated tetrahedrally by two molecules of tetrahydrofuran and two selenium atoms, the other lithium atom exhibits an approximately rectangular-planar coordination by two N,Se-chelating groups. The lithium atoms are bridged by two selenium atoms thus forming a planar Li2Se2 core. Ab initio Hartree-Fock calculations show 1 and the hypothetical symmetric dimer 2 to be of equal energy, whereas the non-chelated dimer 3 is of distinctly higher energy. Exclusive crystallization of 1 is most likely a consequence of its large dipole moment of 6.18 D. Calculations also show that the deformation of the observed geometry around the uniquely coordinated lithium atom in 1 towards distorted tetrahedral or complete planarity leads to an increase of energy. Excessive charge transfer from selenium to nitrogen explains the overwhelming tendency for the N,Se-chelating bonding.
    Additional Material: 6 Ill.
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  • 236
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    Berichte der deutschen chemischen Gesellschaft 130 (1997) 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 237
    ISSN: 0009-2940
    Keywords: Epoxides ; Fluorenyl ligands ; ansa-Zirconocenes, non-symmetrical ; Polymers ; Polymerizations ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Epoxystyrene (1a) were converted into their corresponding alcohols, 2a-c, by treatment with either fluorenyl- or indenyllithium. These alcohols were then further converted into their trifluoromethanesulfonate derivatives, 3a-c. Subsequent reaction of the triflates with fluorenyl-, indolyl-, or tetraphenylcyclopentadienyllithium resulted in formation of 2-(9-fluorenyl)-1(1-indenyl)-1-phenylethane (4a), and 1-(9-fluorenyl)-2-(5-tetraphenylcyclopentadienyl)ethane (4c). The ansa-metallocene (1-(R,S)-2(η5-9-fluorenyl)-1-[η5-1(R,S)-indenyl]-1-phenylethane]ZrCl2 (5a) was prepared from the dilithio salt of 4a. Hydrogenation of 5a with H2/PtO2 leads to {1(R,s)-cyclohexyl-2-(η5-octahydro-9-fluorenyl)-1-[η5-tetrahydro-1(R,S)-indenyl]ethane]ZrCl2 (6a. The complexes 5a and 6a were activated with methylalumoxane (MAO) and used for propene polymerization. The solid state structures of 4b, 4c, and 5a are reported.
    Additional Material: 3 Ill.
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  • 238
    ISSN: 0009-2940
    Keywords: Macrocyclic ligands ; Lanthanides ; Copper ; Polyamines ; Polycarboxylic acids ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The optimized synthesis of two new macrocyclic polyamine polycarboxylic ligands, 1,4,7,10,14,17,20,23-octaazacyclohexacosane-1,4,7,10,14,17,20,23-octaacetic acid (H8OHEC) (10) and 1,4,7, 10,13,16,19,22-octaazacyclotetracosane-1,4,7,10, 13,16,19,22-octaacetic acid (H8OTEC) (12), is presented. The key step in the synthesis of both is the high yield carboxymethylation of the corresponding macrocyclic amines using tert-butyl bromoacetate followed by acidic hydrolysis of the acetate protecting groups. The molecular structures of the intermediates 1,4,7,10,14,17,20,23-octaazacyclohexacosane (OHEC-amine) (8), and octa-tert-butyl 1,4,7,10,13,16,19,22- octaazacyclotetracosane-1,4,7,10,13,16,19,22-octaacetate (OTEC-ester) (11) are determined by X-ray crystal structure analysis. OHEC-amine 8 reacts with 2 equiv. of CuSO4 yielding the dinuclear complex [Cu2(OHEC-amine)](SO4)2 (13). Complex 13 crystallizes with 16 molecules of water. 13 · 16 H2O contains two copper atoms, which are coordinated in a strongly distorted octahedral fashion by four nitrogen atoms, one oxygen atom from the sulfate dianion and one oxygen atom from a water molecule. The new ligands 10 and 12 are fully characterized by 1D- and 2D-NMR spectroscopy. Both ligands form dinuclear lanthanide(III) chelates (Ln=Y, Sm, Eu, Gd, Yb, Lu), which are stable and highly water soluble. With lanthanum(III) only mononuclear complexes are formed.
    Additional Material: 4 Ill.
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  • 239
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    Berichte der deutschen chemischen Gesellschaft 130 (1997) 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 240
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 515-520 
    ISSN: 0009-2940
    Keywords: Water-soluble ligands ; Diazo compounds ; Photolysis ; Cleavage reactions ; Zinc ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The single-crystal X-ray structure analysis of the diazosulfonate p-H2N-C6H4-N=N-SO3Na 3 features a Z configuration of the diazo moiety and a nitrogen-sulfur bond. Each sodium atom is coordinated by one diazosulfonate substitutent in a chelating manner. Upon reaction of 3 with excess salicylaldehyde, the highly water-soluble Schiff base ligand 6 is obtained in good yield. Treatment of ZnCl2 with 2 equiv. of 6 gives the zinc complex 7. In all cases, the solubilizing diazosulfonate groups can be cleaved off photolytically, which offers an opportunity to precipitate the molecules from their aqueous solutions.
    Additional Material: 3 Ill.
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  • 241
    ISSN: 0009-2940
    Keywords: Cobalt ; Cyclopentadienyl complexes ; Heterocycles ; Electrophilic addition ; Insertion reaction ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The cobaltaheterocycles [C5H5Co{κ2(C,S)-C(=CH2)-N(R)C(=S)S](PMe2Ph)] (5-7), which contain both an exocyclic C=C and C=S bond, were prepared from the iminoacylcobalt compounds [C5H5Co(C(CH3)=NCH} (PMe2Ph)]I (2-4) on treatment with either CS2/NaOCH3 or K[S2CNMe2], respectively. While protonation of 5 (R = CH3) and 7 (R = CH2Ph) with HBF4 occurs at the exocyclic C=CH2 bond to give cations containing a CoC(CH3)N(R)C(=S)S ring, the methylation of 5 and 7 with [OMe3]BF4 takes place at the exocyclic C=S bond and generates five-membered heterocycles heterocycles with an SCH4 substituent. The reaction of 5-7 with S8 leads to the elimination of the phosphane ligand and affords the bicyclic dithiolenecobalt complexes 14 - 16 in moderate to good yields. On treatment of 5-7 with C2(CO2R′)2 (R′ = Me,Et), an insertion of the alkyne into the C=CH2 bond occurs and five-membered ring systems 19-22 with an unsaturated exocyclic =C(CO2R′)-C(CO2R′)=CH2 group are formed. As in the case of 5 and 7, protonation and methylation reactions of 19 also take place at different sites leading to cations with either a delocalized CoCN or NCS unit.
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  • 242
    ISSN: 0009-2940
    Keywords: Ligands, tridentate ; Nickel ; Thioethers ; Bioinorganic chemistry ; Racemization ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The complexation behavior of three chiral, tripodal N,O,S-ligands with nickel(II) salts was examined. It was found that the coordination mode of the ligands (bidentate N,O and N,S; tridentate N,O,S) and of the central nickel ion (square-planar vs. pseudo-octahedral) is not simply an intrinsic property of the ligand-metal combination, but also a function of the counter ions and of the solvent of crystallization. In the case of one ligand, a diamagnetic square-planar and a paramagnetic pseudo-octahedral form could be switched back and forth, by just changing the solvent of crystallization from methanol to ethanol. By using an enantiomerically pure tripodal N,O,S-ligand, a metal induced racemization was unveiled which would have otherwise remained undetected.
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  • 243
    ISSN: 0009-2940
    Keywords: Hydroxymethyl phosphanes ; Gold ; Trigonal gold(I) complexes ; Tetrahedral gold(I) complexes ; P ligands ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reactions of water-soluble phosphanes P(CH2OH)3 (1) and Ph2PCH2OH (2) with NaAuCl4 in aqueous or alcoholic media, produced the water/alcoholic-soluble AuI complexes [Au(Ph(CH2OH)3)4]+ (3) and [Au(Ph2PCH2OH)3+ (4) in near quantitative yields. The X-ray structures of 3 and 4, reported in this paper, confirm the structures of these new generation of water-soluble transition metal complexes. All compounds were characterized by 1H-, 13C-, 31P-NMR spectroscopy and mass spectrometry. The structures of 3 and 4 were determined by X-ray crystallography.
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  • 244
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 795-799 
    ISSN: 0009-2940
    Keywords: Boron ; Alkylations ; N ligands ; Dodecaborate ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reactions of the ammine-undecahydro-closo-dodecaborate(1-) anion with alkyl halides have been studied in detail. The degree of alkylation of the nitrogen was found to be dependent upon the steric demands of the alkyl groups. The derivatives were characterized by NMR and infrared spectroscopy. Four compounds were crystallized for single crystal X-ray diffraction studies. The tetrahedral coordination of the nitrogen atom of the bis-alkylated derivatives was found to deviate towards planarity with increasing steric hindrance of the substitutents. - The syntheses, crystal structures, and spectral properties of four N-alkyl derivatives of [H3N—B12H11]-, ammine - undecahydro-closo-dodecaborate(1-) (3), are reported. Alkylation of 3 with ethyl iodide was achieved in dimethyl sulfoxide using potassium hydroxide as base. This led to orthorhombic crystals of [N(nC4H94][(CH3CH2)3N—B12H11] (4). The reaction of 3 with benzyl chloride resulted in the bisbenzylated product, isolated as triclinic crystals of [PPN][(C6H5CH2)2 NH—B12H11] (5). The alkylation of 3 with 2-bromopropane gave a mixture of the mono- and bisalkylated products. The monoalkylated derivative [PPN][(CH3)2CH)NH2-12H11] (6, crystallized in the triclinic space group p1) and the bisalkylated product [PPN]{[(CH3)2NH—B12H11) (7, monoclinic, P21./c) were separated on the basis of their different water solubilities. The solid-state structures of the compounds 4-7 revealed a slight distortion of the B12 icosahedron. The length of the B(1)-N(1) bond was found to be dependent on the steric requirements of the attached amine, e.g. primary amine 〈 secondary amine 〈 tertiary amine. This is demonstrated by the variation in the B—N bond length; from 157.8(2) pm for 6, 158.5(5) pjm for 5, 160.0(3) pm for 7, to 163.7(6) pm for 4.
    Additional Material: 2 Ill.
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  • 245
    ISSN: 0009-2940
    Keywords: Hexafluoroacetone ; Phosphorus, pentacoordinated ; Diphosphane diselenide ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reduction of the isoprene - PCl3 adduct 1 with magnesium powder, or with Si2Cl6, furnished P-chloro-3-methyl-phosphol-2-ene, 2, in satisfactory yield. Further reduction of 2 with Si2Cl6 gave the new trichlorosilyl-3-methylphosphol-2-ene, 3. The reaction of 2 with magnesium powder, with 3, or with 1/2 equivalent of Si2Cl6 provided the new γ3P-γP-diphosphane 1,1′-bi(3-methylphosphol-2-ene) 4. Reduction of 4 with Si2Cl6 led to 3. Oxidation of 4 with selenium gave the 1,2-diphosphane diselenide, 5. The oxidation of 4 with hexafluoroacetone led to a mixture of products, from which a novel tricyclic phosphorane 6 was separated. the structure of 196 was determined by X-ray diffraction; the coordination geometry at phosphorus in distorted trigonal bipyramidal, with a very long equatorial P - C(CF3)2 bond of 193.2(2) pm.
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  • 246
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 823-834 
    ISSN: 0009-2940
    Keywords: Phosphaalkynes ; Phosphaalkyne cyclotetramers ; Cage compounds ; Valence isomerization ; Cyclotetramerization ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In contrast to their all-carbon analogues, phosphaalkyne cyclooligomers only became accessible a few years ago. A milestone in the chemistry of cyclotetramers was the synthesis and structural characterization of the tetraphosphacubane 5, obtained as a thermolysis product of tert-butylphosphaacetylene (1). Since then, the construction of eleven cyclotetramers has been achieved, covering seven different frameworks (A-G). As a consequence of the use of kinetically stabilized phosphaalkynes as starting materials, all known cyclotetramers bear sterically demanding substituents (tert-butyl, tert-pentyl, 1-adamantyl). Cyclotetramerizations are not only achieved by thermolysis of 1, but also by alternative and selective routes such as transition-metal-mediated, Lewis acid- and base-induced processes, as well as by cycloadditions to phosphaalkyne cyclotrimers. Interestingly, these tetramers can be interconverted by various valence isomerizations. The results of thermal and photochemically-induced rearrangements are in good agreement with MO calculations carried out for the parent compounds. Phosphaalkyne cyclotetramers exhibit a highly interesting reactivity and other peculiar features. One outstanding example is the tetraphosphacubane 5, which shows unusual structural and spectroscopic properties as a result of its unique bonding arrangement.
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  • 247
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 843-849 
    ISSN: 0009-2940
    Keywords: P ligands ; Phosphorus heterocycles ; 2-Phosphanylphosphinines ; Dinuclear complexes ; Metal carbonyls ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The 2-phosphanyl-4,5-dimethylphosphinines 1-5 are powerful bridging ligands able to stabilize metal-metal single and triple bonds between low-valent transition metal centres. Their reaction with Mn2(CO)10 in refluxing xylene yields the corresponding Mn2(CO)8 complexes 6 and 7. Reaction with [Fe2Cp2(CO)4] under UV irradiation similarly yields the Fe-Fe-bridged Fe2Cp2(CO)2 complexes 8 and 9. An additional observation is that the 2-phosphininyl-3,4-dimethylphosphaferrocene 10 is formed upon reaction of the 2-phospholylphosphinine 5 with [Fe2Cp2(CO)4] at high temperature under CO pressure. A clean addition occurs at the Mo≡Mo triple bond of [Mo2Cp2(CO)4] to give the Mo-Mo single-bonded complexes 11-15. The thermolysis of these complexes succeeds when the phosphanyl group is a phosphonite P(OEt)2 (13) or P(OAr)2 (14), affording cleanly the Mo2Cp2(CO)4 triple-bonded complexes 16 and 17, respectively. The metal-metal triple bonds of these complexes readily add two molecules of CO to reform 13 and 14, or one molecule of tBu-N≡C to give 18 and 19. The X-ray crystal structure analysis of the MO2C2(CO)4 complex 13a, with the 2-P(OEt)2- phosphinine, shows a gauche orientation of the two Cp rings and very short P-Mo bonds of 2.3565(4) and 2.406(2) Å to the phosphinine and P(OEt)2 groups, respectively.
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  • 248
    ISSN: 0009-2940
    Keywords: Carbene complexes ; Iron ; Alkene complexes ; Carbamates ; Trimethylenemethane complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The title complexes 8 and 9 are easily prepared in two or three steps from iron carbonyls and isobutene diol 5 by Meerwein alkylation of the intermediate acyl complexes 6 and 7. With carbon and heteroatom nucleophiles like enolates and triphenylphosphane they form either stable 4-substituted alkene-carbene complexes 10 and 11, or substituted trimethylenemethane tricarbonyliron complexes like 12. Oxidation with H2O2/NaOH both of the alkene-carbene complexes 11 and of the less stable β-oxo-substituted trimethylene-methane complexes 13, as obtained from reaction of 8 with lithium enolates, yields the corresponding substituted allyl carbamates 15 or the allyl alcohols 14, which are formally bis- and monosubstituted derivatives, respectively, of the starting isobutene diol.
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  • 249
    ISSN: 0009-2940
    Keywords: Asymmetric catalysis ; Cycloadditions ; Lewis acids ; Polymers ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A dimethylpolysiloxane chain is covalently bound to the monomeric Lewis acid catalyst (1R)-(+)-oxovanadium(1V) bis[3- heptafluorobutanoylcamphorate] [(+)-5a] at the C-10 position of the camphor moiety yielding the novel chiral polymeric (1S)-( +)-oxovanadium(1V) bis[3-heptafluorobutanoylcamphorate] -dimethylpolysiloxane [( +)-6a][1]. The Lewis acid promoted hetero Diels-Alder reaction of trans-l-methoxy-3-(trimethylsilyloxy)- 1,3-butadiene (1) and benzaldehyde (2) is studied in the presence of the enantiomerically pure monomeric (5a, 5b) and polymeric (6a, 6b) catalysts. The monomeric and polymeric catalysts of identical chirality[1] invoke opposite enantioselectivities toward the formation of 2-phenyl- 2,3-dihydro-4H-pyrone (4). This remarkable result is corroborated by numerous control experiments. Thus, it is demonstrated that the environment of the active site of the catalyst is changed when the complex is fixed to a polymeric chain. In contrast to 5 and 6, the monomeric 12 and polymeric 13 europium(III) tris[3-heptafluorobutanoylcamphorates] of identical chirality invoke the same enantioselectivity toward the formation of 4. The concept of polymer attachment is utilized to recover the catalyst from the reaction mixture by precipitation and to recycle it for subsequent catalytic runs.
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  • 250
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 899-902 
    ISSN: 0009-2940
    Keywords: Cp3Zr complexes ; Cationic organometallic Lewis acid ; d0-Configured metal complex ; Acetonitrile ; crystal structure analysis of Zirconium ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The organometallic salt [Cp3Zr(N≡C-CH3)]+ [CH3B-(C6F5)3]- (3a) has been prepared by treatment of Cp3ZrCH3 with B(C6F5)3 followed by the addition of acetonitrile. X-ray crystal structure analysis of 3a shows that its cation consists of three uniformly coordinated η5-cyclopentadienyl ligands about the zirconium atom. The acetonitrile ligand is end-on coordinated. In the linear [Zr] -N≡C-CH3 unit the C≡N triple bond [N-C2 1.126(5) Å] is slightly shorter than in the free acetonitrile molecule [dC≡N = 1.141(2) Å], the structure of which was determined as a reference by X-ray diffraction of a crystal obtained by IR-laser-induced zone melting on the diffractometer.
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  • 251
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 947-950 
    ISSN: 0009-2940
    Keywords: Copper ; N ligands ; Copper(I) complexes ; (Imine)copper(I) complexes ; Ketimines ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reactions of [(MeCN)4Cu]BF4 with two or three equivalents of benzophenoneimine lead to the formation of [(Ph2C=NH)2]BF4 (1) and [ (Ph2C=NH)3Cu]BF4 (2), respectively. A further equivalent of the ligand does not coordinate to the cation of complex 2. The crystal structures of both compounds were determined. 1 shows a linearly two-coordinated copper(I) center with a Cu-N distance of 1.877(2) Å. In compound 2 a distorted trigonal planar coordination of copper is observed with N-Cu-N angles of 114.5(2), 112.9(2) and 132.4(2)°, corresponding to two nearly equal Cu-N distances [Cu-N2 1.947(5) and Cu-N3 1.934(5) Å] dnd a significantly longer third one (Cu-N1 2.011(5) Å]. A comparison of these data with recently determined structures of bis(benzophenoneimine)silver(I) and -gold(I) complexes shows that the covalent radii of the monovalent coinage metals decrease in the order Ag(I) 〉 Au(I) 〉 Cu(I).
    Additional Material: 3 Ill.
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  • 252
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Air oxidation of (Oxydi-2,1-phenylene)(2-phenoxyphenyl)stibane (1) gives the phenoxystibane oxide [(2-PhOC6H4)O(C6H4)2Sb]2O2 (2). Single crystals of (o-Tol2Sb)4- O4(O2)2 (3) were obtained by air oxidation of o-TolSb-(SiMe3)2. Crystal structures of 2 and 3 are reported.
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  • 253
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 975-980 
    ISSN: 0009-2940
    Keywords: Zinc complexes ; Phenoxide complexes ; Alkoxide complexes ; Terminal alkoxide ligands ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The zinc hydroxide complexes Tp*Zn-OH of highly substituted pyrazolylborate ligands react with phenols, and alcohols, of sufficient acidity, in a condensation reaction with release of H2O. Starting with phenols the following were attached:phenolate, p-nitropehnolate, o-vanillinate, o-hydroxymethylphenolate, o,o-bis(hydroxymethyl) -p-methylphenolate. Whilst aliphatic alcohols and benzyl alcohol did not react, their derivatives, with highly electronegative substituents could be incorporated. Thus, the arylmethoxides OCH2C6F5 and OCH2C6H4NO2-p, as well as the alkoxides OCH2CF3 and OCH2CCl3, were attached. 2-Mercaptoethanol was bound via its thiolate function. The crystal structures of TpCum,Me ZN-OC6H4NO2-p,TpCum,Me ZN-OCH2-C6F5, TpCum,Me ZN-OCH2CF3, TpCum,Me ZN-OCH2CCl3 and TpCum,MeZn-SCH2CH2OH were determined.
    Additional Material: 5 Ill.
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  • 254
    ISSN: 0009-2940
    Keywords: Methylcyclopentadeienyl molybdenum(V) tetrachloride ; Primary Phosphane ligands ; EPR spetroscopy ; Molybdenum ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: [Cp′MoCl4(CH3CN) (Cp′=C5H4Me) react with 2,4,6-triisopropylphenylphosphane or cyclohexylphosphane to give the phosphane complexes [Cp′MoCl4(PH2R)] [R=2,4,6-Pri3C6H2 (1)]. 1 and 2, were characterized spectroscopically (IR, MS) and by crystal structure determinations. EPR investigations in liquid and frozen solution confirmed the presence of Mo(V) species and the data were used to analyze the spin-density distribution in the first coordination sphere.
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  • 255
    ISSN: 0009-2940
    Keywords: Lithium 5-Methyl-1,3-dithia-5-azacyclohex-2-ylborate - 5-borane ; 5-Methyl-1,3-dithia-5-azacyclohex-2-yllithium ; Nitrogen heterocycles ; Sulfur heterocycles ; Lithium ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Syntheses of the dimers of axial 5-methyl-2-dithiazinyllithium (4) and equatorial 5-methyl-2-diethiazinyllithium-5-borane (5), and lithium 5-methyl-2-dithiazinanylborate-5-borane (6) are reported. Compounds 4, 5, and 6 are configurationally and conformationally stable. The 1H-, 13H-, 13C-, 11B-, and 7Li-NMR study of th reactions of 4 and 5 with BH3—S(CH3)2, BH3 - THF, and CH3I is presented.
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  • 256
    ISSN: 0009-2940
    Keywords: Lanthanoid complexes ; Ytterbium ; Neodymium ; 2,6-Diphenylphenolate complexes ; Aryloxide complexes ; Lanthanoides ; O ligands ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reduction of [Yb(Odpp)3(THF)2(HOdpp = 2,6-diphenylphenol; THF = tetrahydrofuran) with ytterbium powder and mercury metal yields [Yb(Odpp)2(THF)3] (1) which on crystallization from DME gives [Yb(Odpp)2(DME)2] (2) (DME = 1,2-dimethoxyethane). Crystallization of the reactant [Yb(Odpp)3(THF)2] from DME yields [Yb(Odpp)3(DME)]. (DME)0,5 (3) and of [Nd(Odpp)3(THF)2] from DME/THF the analogous [Nd(Odpp)3(DME)]. (THF) (4). The X-ray crystal structure of 1 reveals distorted trigonal bipyramidal five-coordinate ytterbium with axial Odpp ligands [O-Yb-O 164.6(3)˚], and unsymmetrically distributed equatorial THF ligands [O-Yb-O 137.5(3), 138.8(3), 83.7(4)°] owing to two close H(Ph)...Yb approaches (3.1-3.2 Å). In 2, there is trigonal prismatic six-coordination with an Odpp ligand on each triangular face and DME ligands bridging the triangular faces. Both 3 and 4 have distorted square planar five-coordination for the lanthanoid metals with an apical Odpp ligand and cisoid Odpp ligands and a chelating DME in the square plane.
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  • 257
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 887-890 
    ISSN: 0009-2940
    Keywords: Asymmetric catalysis ; Epoxidation ; Oxidation ; Vanadium ; Sulfur ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The syntheses and X-ray crystal structures of two chiral bis[2-(oxazolinyl)phenolato]-oxovanadium(IV) complexes are reported. Their catalytic activity in oxidative transformations and C-C bond-forming reactions has been investigated.
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  • 258
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 903-906 
    ISSN: 0009-2940
    Keywords: Hexaphenyltantalate ; Hexatolytantalate ; Trigonal prismatic coordination ; Transition metals ; Structure elucidation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: By reacting TaCl5 with LiC6H5 and LiC6H4-4-CH3 salts, the anions Ta(C6H5)6 and Ta(C6H4-4-CH3)6 were obtained in small yields. They were structurally characterized by low-temperature single-crystal structure determination and found to have quite similar structures, which can be described as slightly distorted trigonal prismatic.
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  • 259
    ISSN: 0009-2940
    Keywords: Alkynes ; Allenes ; Furans ; Palladium ; Catalysis ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: By making the choice of either PDCl2(MeCN)2 or PTH rac-4 as catalyst, the allenyl ketones 1 could be preferentially cycloisomerized/dimerized to either 2,4-disubstituted furans 3 or preferentially cycloisomerized to the monosubstituted furans 2. Since the PTH catalyst tolerates functional groups like terminal alkynes, α-halogen ketones, and alkyl halides that inhibit the silver catalysis, the latter method is an important extension of Marshall's Ag1-catalyzed isomerization of 1 to 2. Some of these latter reactions also showed exciting chemoselectivities, e.g. with allenyl ketones, such as 1c and 1d, which also also possess a 1,6-enyne substructure, no enynecyclization was observed. This is also the first reported example of catalysis by a PTH.
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  • 260
    ISSN: 0009-2940
    Keywords: Rhodium ; Cations ; Tridentate ligand ; Alkene complexes ; P Ligands ; N ligands ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The cationic rhodium(1) complexes [Rh(PNP)(C2H4)]X; X = BF4 (1a), PF6 (1b), CF3SO3 (1c ) were prepared by addition of the tridentate ligand 2,6-bis(diphenylphosphanylmethyl)pyridine (PNP) to a solution of [Rh(C2H4)2(solv)2]X (solv = acetone or THF) under ethylene. The complexes were characterized by IR and 1H-, 13C-, and 31P-NMR spectroscopy. The coordination of two ethylene molecules at the [Rh(PNP)]+ fragment could be detected by dynamic proton resonance of a solution of 1a under free ethylene. The styrene complex [Rh(PNP)(styrene)]BF4 (4) was obtained by substitution of the ethylene from 1a with an excess of styrene. The π coordination of C2H4 and styrene in 1a and 4 respectively was confirmed by X-ray crystal structure analysis. The olefin complexes react with an excess of the secondary amine to give the corresponding amine complexes [Rh(PNP)(HNR2)]X; HNR2 = piperidine (5), HNMe2 (6 ), HNEt2 (7). Conversly, the amine could be released from the amine complexes with an excess of ethylene at low temperature by the formation of the ethylene complex 1.
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  • 261
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 955-958 
    ISSN: 0009-2940
    Keywords: Phosphane sulfides ; Gold(I) complexes ; Sulfide coordination ; Phosphorus ; Sulfur ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Treatment of the ditertiary phosphane sulfides (CH2)n[PPh2S]2, 1a-1d, n = 1-4, with equivalent amounts of (dimethylsulfide)gold(I) chloride (Me2S)AuC1 affords the dinuclear complexes 2a-2d with an AuCl unit attached to each sulfur atom. The chlorides can be converted into the bromides 3a-3c by metathesis using KBr, or by reacting 1d with (tetrahydrothiophene)gold bromide. With [(Ph3P)Au]+ O3SCF3 as the aurating agent for the diphosphane disulfides, the corresponding dicationic products are obtained: {(CH2)n[SPPh2AuPPh3]2}2+ · 2 O3SCF3 (4b-4d, n = 2-4). An excess of the reagents does not lead to polygold clustering at the sulfur atoms, and P-S cleavage occurs instead to give sulfonium salts {S[Au(PPh3)]3}+ X-. The reaction of Ph3PS with equimolar quantities of [ (Ph3P)Au]O3SCF3 leads to the cationic 1:1 complex 5, and with an excess of the agent the P-S bond is ruptured. The structures of compounds 4b and 4d were determined by single-crystal X-ray diffraction. The dications have crystallographic centers ot inversion, the coordination at the gold atoms is linear [4b: 179.03(3)° 4d: 175.29(2)°] and the angles at the sulfur atoms are acute [4b: 97.76(4)° 4d: 96.37(3)°], but there are no short Au-Au contacts.
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  • 262
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 969-973 
    ISSN: 0009-2940
    Keywords: Catecholamide ; Protochelin ; Ligand-promoted dissolution ; Iron ; Siderophores ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Protochelin, the tris(catecholamide) siderophore recently identified in the culture medium of A. vinelandii, can be synthesised by coupling of suitably protected azotochelin and aminochelin derivatives in preparative yields, Based on the ligand protonation constants of pK1 = 6.67, pK2 = 8.09 and pK3 = 9.68, the proton-independent stability constant for ferric protochelin could be estimated to be 1044.6. The solubilisation of FeIII hydroxide by protochelin has been investigated spectrophotometrically in aqueous solution at pH = 7. Since the production of protochelin by A. vinelandii depends on high molybdate levels in the growth medium, the studies have been carried out in the presence as well as in the absence of an equimolar amount of molybdate. Although the protochelin promoted dissolution of FeIII hydroxide is delayed significantly in presence of molybdate, the effect is far less pronounced than the one observed for azotochelin, the bis(catecholamide) siderophore of A. vinelandii.
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  • 263
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1261-1267 
    ISSN: 0009-2940
    Keywords: Single-component metallocene catalyst ; Olefin insertion ; Organometallic ions pairs ; (Alkene)metallocene complex ; Metallocene betaines ; C-C coupling ; Zirconium ; Homogeneous catalysis ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Treatment of the (butadiene)ML2 complexes 1 [ML2 = Cp2Zr (a), Cp2Hf (b), and (.-C5H4CH3)2Zr (c)] with B(C6F5)3 gives the 1:1 addition products (CH2CHCHCH2-B(C6F5_3)ML2 (3a-c). At -40°C the betaine complex 3a inserts one equivalent of methylenecyclopropane to give the regioisomeric insertion products 5a and 6a in a 60:40 ratio. These products exhibit the cyclopropylidene moiety in the α- and β-positions, respectively, relative to zirconium. The corresponding hafnocene complexes 5b and 6b are obtained in a 70:30 ratio starting from 3b. The reaction of 3(a-c) with allene gives a single insertion product (7a-c) in each case where the exo-methylene group is in the α-position to the metal center ([2,1]-insertion). The complexes 5-7 are chiral. They all exhibit a pronounced ·-interaction of the internal -C4H=C5H- double bond of the s̰-ligand chain with the metal center in addition to a metallocene/-C6H2-[B] ion pair interaction. The relative contributions of the cationic metallocene end of the dipolar complexes 5-7 are quite dependent on the steric and electronic properties of the respective metallocene units involved. This is revealed by a comparison to typical 13C-NMR parameters of the complexes 5-7 with a pair of suitable model complexes, namely the ethylene insertion product 4 into the betaine system 3a and its THF adduct 4.THF.
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  • 264
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1279-1294 
    ISSN: 0009-2940
    Keywords: Tripodal ligands ; Aminolytic cleavage of oxetanes ; Tripod molybdenum compounds ; Mixed donor set ligands ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The preparation of neopentane-based tripod ligands CH3C(CH2X)(CH2Y)(CH2Z( 3 (X = NR2, NHR; Y = PR2; Z = PR2, SR, S-) in a convergent manner is described. The procedure is based on the aminolytic cleavage of functionalized oxetanes CH3C(CH2OCH2)CH2R 1 by primary or secondary amines, leading to functionalized amino alcohols CH3C(CH2NHR)(CH2OH)(CH2R) or CH3C(CH2NR2)-(CH2OH)(CH2R) 2. The appropriate activation of the R (e.g. OR) and OH groups present in 2 allows for substitution vs. SR or PR2 donor functions. Depending on the nature of the groups present in each reaction step, various protection and groups present in each reaction step, various protection and deprotection steps have to be taken in the course of this type of preparation of the tripod ligands 3. By reaction with (CH3CN)3Mo(CO)3, ligands 3 form Mo(CO)4 derivatives 4 or Mo(CO)3 derivatives 5, depending on the reaction conditions. In compounds 4, the ligands are coordinated in a bidentate mode with the soft donor atoms (P, S) coordinated and the hard donor function playing the role of the dangling arm. In the trihapto bonding mode present in 5, all three donor functions, two soft (P, S) and one hard (NHR′, NR′2), are coordinated. The two types of coordination compounds may be interconverted: 4e (X = NMe2′ Y = PPh2, Z = SiPr) with a non-coordinating CH2NMe2 group is transformed into 5c upon photolytic decarbonylation. Under 1 bar CO at 20°C, 5c reverts to 4e. X-ray structure analysis of a series of compounds of types 4 and 5 reveals characteristics of the relevant conformational patterns. All compounds have been fully characterized by the standard analytical techniques (NMR, MS), as well as elemental analysis.
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  • 265
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1333-1338 
    ISSN: 0009-2940
    Keywords: Gold ; Gold(I) complexes ; Phosphinite complexes ; Phosphite complexes ; Configuration determination ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of compounds (R3P) AuMe with diphenylphosphinous acid Ph2P(O)H affords methane and neutral complexes of the type (R3P(O)Ph2 (1a: R = Me; 1b: R = Ph, lc: R = o-Tol). 1a, b are obtained in high yield, but the yield of lc is lower owing to a side-reaction which leads to a different product: Ph2P(OH)-Au-P(O)Ph2 (2). The crystal structure of 1a was determined by a single-crystal X-ray diffraction study. The compounds is a monomer with a linear P-Au-P′ axis and the phosphane and phosphinite ligands in a staggered conformation. In solution (CHCl3, CH2Cl 2/) compounds 1a-c undergo a ligand redistribution, establishing equilibria that involve ionic isomers of the type [R3P)2Au]+ [Au-(P(O)Ph2)2]-, which are readily identified through their NMR data. The analogous reaction of (R3P)b AuMe with dimethylphosphite (MeO)2P(O)H gives methane and the corresponding dimethylphosphites of the type (R3P)AuP(O)(OMe)2 (3a: R = Me; 3b: R = Ph; 3c: R= o-Tol). The crystal structure of 3b has also been determined. It features a linear structure with an eclipsed conformation of the ligands. In polar solvents (CHCl3, methanol) there is again an eqilibrium between neutral and ionic isomers, the latter comprising bis(phosphane)gold cations [(R3P)2Au]+ and {Au[P(O)-(OMe)2]2)- anions, as confirmed by NMR spectroscopy and mass spectrometry.
    Additional Material: 5 Ill.
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  • 266
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1353-1359 
    ISSN: 0009-2940
    Keywords: 113Cd NMR ; Multidentate ligand ; Multinuclear metal complex ; Piperazine ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Eleven novel piperazine containing open-chain ligands L1-L11 were designed to offer symmetrical and asymmetrical complexation sites for metal ions and were synthesized by repetitive synthetic method. The divergent use of aromatic bishalomethyl and mono-N-alkylated piperazine compounds as spaces led toa series of long (up to M. W. = 836) oligomeric multidentate N-ligands. Due to the lack of solid state methods for structure analysis, an NMR technique using 113 Cd nucleus as a probe in solution state was utilised. 113 Cd chemical shifts were observed to be dependend on the coordination site and similar coordination sites in different ligands gave characteristically similar 113 Cd chemical shifts. As a result 113 Cd-NMR spectroscopy proved to be an excellent tool to distinguish between the structures of the different complexation sites on a nearly quantitative level.
    Additional Material: 3 Ill.
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  • 267
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1365-1374 
    ISSN: 0009-2940
    Keywords: N ligands ; Chelates ; Coordination modes ; Ligand effects ; Structure-activity relationships ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Monoanionic bi- and tridentate ligand systems emulating the structural features of the well-known poly(pyrazolyl)borates are created by bridging heteroaromatic rings with formally negatively charged p-block elements. Their properties and versatility are exemplified by their complexes with main group metals. Due to their N(σ)-donating and π-interacting ability, as well as the flexibility of the substituent bonding, these ligand systems have the potential to adapt both geometrically and electronically to the coordination requirements of the complexed metal. Within these complexes, the heteroaromatic substituents operate as charge spacers between the formally anionic center and the metal cation without encapsulating either site. This provides possible applications in the creation of reactive soft/hard bimetallic reagents, the realization of multinuclear arrays, and the design of preorganized CVD precursors, particularly en route to III/V-semiconducting thin films.
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  • 268
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1411-1416 
    ISSN: 0009-2940
    Keywords: Phosphane-boranes ; Boranes ; Phosphanes ; Umpolung, attempted ; Bond polarity ; Configuration determination ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reactions of (Me2S)BH2Br and (Me2S)BHBr2 with equimolar quantities of 1,2-bis(diphenylphosphanyl)ethene (1) or -benzene (2) lead to cyclic, cationic bis(phosphane)boranes [4[(1)BH2]+ Br-; 6: [(2)BH2]+ Br; 7: [(2)BHBr]+ Br-]. The Br counterions can be exchanged in metathesis reactions (e.g. with AgBF4 to afford 4a). The tritertiary phosphane bis[2-(diphenylphosphanyl)phenyl]phenyl-phosphane (3), reacts with (Me2S)BHBr2 to give bicyclic dicationic tris(phosphane)borane 8, [(3)BH]2+ Br-, which can be converted into the bis(hexafluorophosphate) 8a using NH4PF6. All compounds have been characterized by analytical and NMR-spectroscopic data. The crystal and molecular structures of 5 - 7 have been determined by single-crystal X-ray diffraction. The five-membered rings C2P2B have an envelope conformation and show no sign of electron delocalization. Attempts to deprotonate the B—H functions in 5 - 8 have not been successful. Clearly, the two (5 - 7) or three phosphonium centers (8) adjacent to the boron atom are not sufficient to induce an “umpolung” of the B—H group
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  • 269
    ISSN: 0009-2940
    Keywords: Metal - metal bonds ; Insertion reactions ; Group-13 monochlorides ; Main-group elements ; Nickel ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The dinuclear compound [{(η5 - Cp)Ni(PEt3)}2] (1) containing an unbridged Ni-Ni bond reacts with the heavier group 13 monochlorides [{CH(SiMe3)2)2}AlIIICl], InCl, and TlCl by scission of the metal-metal bond. In the case of InCl and TlCl the chloro-bridged dimmers [{(η5-Cp)Ni(PEt3)2ECl2Ecl}2] (E = In 2, Tl 5) were formed. The Tl compound 5 is unstable and decomposes via disproportionation a and formation of the halogen-free Tl [III] compound [{(η5-Cp)Ni(PEt3)}3Tl] (6). 2 can be dehalogenated with activated magnesium to yield the halogen-free In [III] compund [{(η5-Cp}Ni(PEt3)}3In] (4). The Ga analogue of 4 and 6 [{(η5-Cp)Ni(PEt3)}3Ga] (7) is accessible by a conproportionation of 1 with Ga metal in refluxing THF. In contrast to InCl and TlCl the aluminium (III) monochloride [{CH(SiMe3)2}2AlCl] reacts with 1 by a ligand redistribution reaction and formation of the salt [{(η5-Cp)Ni(PEt3)2]+-[{CH(SiMe3)2]2AlCl]2-. (8). Elemental Hg or Mg amalgam show the same activity as elemental Ga towards 1 and insert into the Ni—Ni bond by forming the linear Hg-bridged complex [(n3-Cp)Ni(PEt3)]2Hg] (9). The molecular structures of 2, 4, 8, and 9 were determined by X-ray crystallography. The In atom in 4 has a distorted trigonal-planar configuration with the central In atom being surrounded by three [(n5-Cp)Ni(PEt3)] fragments. 4 represents the first Ni-In cluster containing exclusively unsupported In - Ni bonds, as well as the first carbonyl-free Ni - In cluster. On the basis of spectroscopic data the same structure is assigned to the Ga and Tl analogues of 4. The Ni—Hg—Ni arrangement in 9 is exactly linear, as determined by X-ray crystallography.
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  • 270
    ISSN: 0009-2940
    Keywords: Schiff bases ; Polyene dialdehydes ; α-Amino acids ; Pantamethylcyclopentadienyl complexes ; P ligands ; Iridium ; Palladium ; Platinum ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Schiff bases 1—11 were synthesized from α-amino acids or o-aminophenol and crocetindialdehyde, 2,7-dimethyloctatrienedial, terephthalaldehyde, or β,β′ -p-phenylendiacroleine. The reactions of these Schiff bases with chloro-bridged complexes [(R3P)(Cl)M(η-Cl)]2 (M = Pd, Pt) and [(C5Me5)(Cl)Ir(°Cl)]2 gave the dinuclear complexes 12-31.
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  • 271
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1495-1498 
    ISSN: 0009-2940
    Keywords: Deltacyclenes ; Deltacyclanes ; P-H addition reactions ; Chiral phosphanes ; Enantioselective catalysis ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The suitability of enantiomerically pure deltacyclenes as building blocks in the synthesis of expanded phosphanes was examined. Different substituted deltacyclenes were irradiated with diphenylphosphane and three bisphosphanyl derivatives. With these P—H addition reactions, new chiral deltacyclane-derived phosphorus ligands were synthesized. They were tested in the Rh-catalyzed asymmetric hydrogenation of (Z)-(ã)-N-acetamidocinnamic acid and in the Pd-catalyzed asymmetric allylation of 1,5-dimethylbarbituric acid.
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  • 272
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1519-1527 
    ISSN: 0009-2940
    Keywords: Phosphorus ; Heterocycles ; Phosphorus ylides ; Phosphoranediyl ; Phosphonio substituents ; P-Cl bond dissociation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The 1,3-dichloro- and 1,3-dibromo-substituted title compounds 5b, c result from the condensation of triphenylphosphonium-bis(trimethylsily1)methylide 1 with PC13 and PBr3. The chloro derivative 5b undergoes a variety of single and double substitution reactions, of which some have merely been tested and others have been made preparative use of. The substitution of one chloride by an ylidyl, amino, phosphino, or metal carbonyl group is accompanied by the spontaneous dissociation of the other P-CI bond to yield the, 1,3-diphosphetenium chlorides 14/15, 19, 31 and 36, respectively. In other cases (9, 27, 32) dissociation can be achieved by means of a Lewis acid. Protonation of 5b occurs at the carbon ring members; methylation and formation of transition metal complexes occurs at a phosphorus ring member. PCl3 degrades the four-membered ring of5b or enlarges the ring to yield 3,5-diphosphoranediyl-l,2,4-triphospholane derivatives 39, 40, 42.
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1539-1546 
    ISSN: 0009-2940
    Keywords: Chiral tin hydrides ; Chiral hydrogen donors ; Tin ; Ligand effects ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of the chiral tin bromides 1-4 and hydrides 5-8, containing the potentially bidentate, optically active 2-[ (1 S/R)- 1 -dimethylaminoethyl]phenyl and 2 -[( 1 S) - 1 -dimethylamino-2,2-dimethylpropyl]phenyl ligands, is reported. The tin hydrides 5-8, with the tin atom as the stereogenic centre, were isolated as diastereomeric mixtures with diastereomeric ratios of dr = 50:50 up to dr = 80:20. The absolute configuration of ( - ) - (1 S)- 1 - (2-bromophenyl) -2,2-dimethylpropylamine [(S)-10] was determined by single-crystal X-ray structure analysis.
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  • 274
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    Berichte der deutschen chemischen Gesellschaft 130 (1997) 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 275
    ISSN: 0009-2940
    Keywords: Chromium ; Chromium(0) complexes ; Cyclooctatetraene complexes ; Photochemistry ; Cycloadditions ; Photochemical [6+2] cycloadditions ; Dienes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Tricarbonyl(η6-1,3,5,7-cyclooctatetraene)chromium (1) yields upon UV irradiation in ether at 233 K with 2,3-dimethyl-1,3-butadiene (2) or 2-methyl-1,3-butadiene (3) by [6+2] cycloadditions the correspondingly substituted tricarbonyl(η6-bicyclo[4.2.2]deca-2,4,7-triene)chromium complexes 4, 5a and 5b. With ammonium cerium(IV) nitrate the organic ligand of complex 4, 9-isopropenyl-9-methyl-bicyclo[4.2.2]-deca-2,4,7-triene (6) is liberated. The complexes 4, 5a and 5b were characterised by IR and NMR spectroscopy, the ligand 6 by NMR spectroscopy.
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1801-1805 
    ISSN: 0009-2940
    Keywords: Phosphene ; cyclophosphane isomerism ; Phosphorus Ylides ; NMR spectroscopy ; Structure elucidation ; Transanular interaction ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of two specific ylidyl dichlorophosphanes, Ph3P=CR-PCl2, with P(SiMe3)3 yields the ylidyl trimethylsilyl diphosphenes Ph3P=CR.P=P-SiMe3 as primary products which form two different types of dimers: the cyclotetraphosphane 9 (R = SiMe3), and the tetraphosphene 10 (R = 2,6-Cl, 2,/C6H3). The latter compound is readily converted to the bis(ylidyl)biocyclotetraphosphane 11. The molecular structures of 9 and 11 allow a strong transanular interaction between teh ylide-substituted phosphorus atoms, which results in very large two-bond coupling constants (2Jpp = 184 and 332 Hz respectively). The central P bond in 11 is relatively long (220.7 pm); quantum chemical calculations show the lengthening to be a consequence of the perpendicular orientation of the ylidic donor p-orbital.
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    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1813-1814 
    ISSN: 0009-2940
    Keywords: Amines ; Gold(I) ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction between (tht)AuCl (tht = tetrahydrothiophene) and neat pyrrolidine (L) leads to the compound L4Au3Cl3. An X-ray structure determination reveals the presence of molecules LAuCl and ions L2Au+ and Cl-, in the ratio 2:1:1. The packing is characterised by Au.Au contacts and N-H-Cl-hydrogen bonds.
    Additional Material: 2 Ill.
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  • 278
    ISSN: 0009-2940
    Keywords: Macrocycles ; Benzomolybdacrown ethers ; Host-guest chemistry ; Stability constants ; NMR titration ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of the diphosphanes 2a-i with (OC)4Mo(nbd) under high dilution conditions affords the mononuclear benzomolybdacrown ethers cis-(OC)4Mo{1,2-, 1,3-, 1,4-[PH2PCH2(CH2OCH2)πCH2]2C6H4-P, P′] (3a-i) (n = 1, 2). On the basis of the 31P nucleus the inclusion behavior of the molydacycles 3a-i toward the alkali metal salts LiBF4 and NaBPh4 was investigated with the aid of a NMR titration technique by using the program EQNMR. Only 3dshows an interaction with the alkali metal cation Na+ forming a 1:1 and 2:1 complex (3d/cation) while no interaction with Li+ could be detected. The molecular structures of 3a and 3d were elucidated by X-ray structural analyses. Complexes 3a and 3d crystallize in the monoclinic space groups P21/c and P21/n with Z = 8 and 4, respectively.
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  • 279
    ISSN: 0044-2313
    Keywords: Magnesium Compounds ; Phosphoraneiminato Complexes ; Crystal Structures ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Phosphaneimine and Phosphoraneiminato Complexes of Magnesium. The Crystal Structures of [MgBr1,25I0,75(Me3SiNPMe3)(OEt2)], [MgI2(Me3SiNPMe3)2], [Mg2I2(Me3SiNPMe2CH2)(Me3SiNPMe2CH2CH(Me)O)(OEt2)], and [MgBr(NPMe3)]4 · C7H8By reactions of the silylated phosphaneimine Me3SiNPMe3 with the Grignard reagents EtMgBr and MeMgI, respectively, the carbanionic phosphoraneiminato derivatives [XMg(CH2PMe2NSiMe3)]n (X = Br, I) can be isolated as main products. The by-products of these reactions, [MgBr1.25I0.75(Me3SiNPMe3)(OEt2)], [MgI2(Me3SiNPMe3)2] and [Mg2I2(CH2PMe2NSiMe3)(O(Me)CHCH2PMe2NSiMe3)(OEt2)] were identified by crystal structure determinations. The phosphoraneiminato complex [MgBr(NPMe3)]4 · C7H8 with hetero cubane structure is formed by a metathesis reaction of [ZnBr(NPMe3)]4 with RMgBr (R = Ph. Mes).
    Notes: Als Hauptprodukte der Umsetzungen des silylierten Phosphanimins Me3SiNPMe3 mit den Grignard-Reagentien EtMgBr und MeMgl wurden die carbanionischen Phosphaniminato-Derivate [XMg(CH2Pme2NSiMe3)]n (X = Br, I) isoliert. Als Nebenprodukte wurden [MgBr1,25I0,75(Me3SiNPMe3)(OEt2)], [Mgl2(Me3SiNPMe3)2] und [Mg2I2(CH2PMe2NSiMe3)(O(Me)CHCH2PMe2NSiMe3(OEt2)] durch röntgenographische Strukturanalysen identifiziert. Den Phosphaniminato-Komplex [MgBr(NPMe3)]4 · C7H8 mit Heterocuban-Struktur erhielten wir durch Metathese-Reaktion aus [ZnBr(NPMe3)]4 und RMgBr (R = Ph, Mes).
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  • 280
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    Zeitschrift für anorganische Chemie 623 (1997), S. 1074-1080 
    ISSN: 0044-2313
    Keywords: Pentachloromonocarbonylosmate(III) ; Crystalline Hydrate ; Crystal Structure ; Vibrational Spectra ; Normal Coordinate Analysis ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis, Crystal Structure, Vibrational Spectra, and Normal Coordinate Analysis of K2[OsCl5(CO)] · H2OThe X-ray structure determination of K2[OsCl5(CO)] · H2O (monoclinic, space group P21/c a = 13.600(2), b = 7.122(1), c = 22.186(11) Å, β = 98.66(3)°, Z = 8) revealed two crystallographic independent bat very similar complex anions [OsCl5(CO)]2- with rough C4v point symmetry. Due to the stronger trans influence of the carbonyl group the bond lengths in the Cl—Os—CO axis Os—Cl = 2.449(2), 2.430(2) Å are langer as compared with the octahedron basis Os—Cl = 2.340-2.370 Å. The water of crystallization is coordinated to potassium (K—OH2 = 2.625-2.815 Å). Using the molecular parameters the IR and Raman spectra are assigned by normal coordinate analysis. The valence force constants are fd(CO) = 15.30, fd(OsC) = 3.88, fd(OsCl) = 1.81, fd(OsCl) = 1.36, fd(OH) = 7.65, 7.82, 7.79 mdyn/Å. The strengthening of the Os—C bond by stronger back donation of the OsIII(d5) complex in comparison with the isostructural OsIV (d4) compound is discussed.
    Notes: Die Röntgenstrukturanalyse von K2[OsCl5(CO)] · H2O (monoklin, Raumgruppe P21/c a = 13,600(2), b = 7,122(1), c = 22,186(11) Å, β = 98,66(3)°, Z = 8) hat gezeigt, daß zwei kristallographisch unabhängige aber sehr ähnliche Komplexanionen [OsCl5(CO)]2- mit annähernd C4v-Punktsymmetrie vorliegen. Durch den größeren trans-Einfluß der Carbonylgruppe sind die Bindungsabstände in der Cl—Os—CO Achse Os—Cl = 2,449(2), 2,430(2) Å länger als in der Oktaederbasis: Os—Cl = 2,340-2,370 Å. Das Kristallwasser ist an Kalium koordiniert (K—OH2 = 2,625-2,815 Å). Mit den röntgenographisch bestimmten Molekülparametern lassen sich die IR- und Raman-Spektren durch Normalkoordinatenanalyse zuordnen. Die Valenzkraftkonstanten betragen fd(CO) = 15,30, fd(OsC) = 3,88, fd(OsCl) = 1,81, fd(OsCl) = 1,36, fd(OH) = 7,65, 7,82, 7,79 mdyn/Å. Die Festigung der Os—C-Bindung durch stärkere Rückbindung in dem OsIII(d5)-Komplex im Vergleich zur isostrukturellen OsIV(d4)-Verbindung wird diskutiert.
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  • 281
    ISSN: 0044-2313
    Keywords: (Borylorganyl)phosphanes ; (Borylorganyl)phosphoniumsalt ; X-ray structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthese und Reaktionen von {o-{[Bis(dimethylamino)boryl]methyl}phenyl}diphenyl-phosphanDas neue α,ω-[Boryl(organyl)]phosphan o-Ph2PC6H4CH2 (NMe2)2 (10) wurde synthetisiert und spektroskopisch charakterisiert. Die Reaktivität dieser Verbindung, vor allem gegenüber Substitutionsreaktionen am Boratom war der Gegenstand unserer Untersuchungen. Verbindung 10 reagiert mit MeOH, BCl3 bzw. HCl zu den Verbindungen o-Ph2PC6H4CH2B(OMe)2 (10 a), o-Ph2PC6H4CH2BCl2 (10 c), o-Ph2PC6H4CH2BCl2 (HNMe2) (10 d) und o-Ph2P(HCl)C6H4CH2 BCl2(HNMe2) (10 e). Die Umsetzung von 10 a mit LiAlH4 führt zu o-Ph2PC6H4CH2BH2 (10 b). Verbindung 10 e wurde zusätzlich durch eine Röntgenstrukturanalyse charakterisiert.
    Notes: The new α,ω-[boryl(organyl)]phosphane o-Ph2PC6H4CH2B (NMe2)2 (10) was obtained in good yields from the reaction of CIB(NMe2)2 with o-Ph2PC6H4CH2Li(tmeda). Five derivatives of 10 were obtained by substituting the boron-bound amino groups by reactions with MeOH, BCl3, HCl, and LiAlH4, respectively, in particular, o-Ph2(HCl)PC6H4CH2BCl2 (HNMe2) (10 e) which shows a unique P—H—Cl—H—N unit. Compound 10 and its derivatives were characterized by multinuclear NMR methods, mass spectra, and elemental analyses. In addition, the structure of 10 e · 1.5 C6H6 was determined by single crystal X-ray diffraction.
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    Zeitschrift für anorganische Chemie 623 (1997), S. 1108-1112 
    ISSN: 0044-2313
    Keywords: Sodium tetra amido manganate(II) ; sodium manganese (II) amide ; X-ray structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Na2Mn(NH2)4: A New Type of Layered StructureThe structure of Na2Mn(NH2)4 was solved by X-ray single crystal data including H-positions: P21/c, Z = 4, a = 6.331(1) Å, b = 14.542(3) Å, c = 7.212(1) Å, β = 116.29(1)°, Z(F20 ≥ 3σ = (F20)) = 1343, Z(parameters) = 96, R/RW = 0.023/0.029.The compound crystallizes in a new type of structure. Within layered blocks the amide ions are arranged with the motif of a hexagonal closest packing of spheres. Within these blocks alternating layers contain sodium in all octahedral sites and manganese in an ordered way in a quarter of tetrahedral sites.
    Notes: Die Struktur von Na2Mn(NH2)4 wurde röntgenograhisch über Einkristalldaten einschließlich der H-Lagen bestimmt: P21/c, Z = 4, a = 6,331(1) Å, b = 14,542(3) Å, c = 7,212(1) Å, β = 116,29(1)°, Z(F0) mit (F0)2 ≥ 3σ(F0)2 = 1343, Z(Parameter) = 96, R/RW = 0,023/0,029.Die Verbindung kristallisiert in einem neuen Strukturtyp. Die Amidionen bilden innerhalb von Schichtenpaketen das Motiv einer hexagonal dichtesten Kugelpackung. In ihr sind in einzelnen Ebenen abwechselnd entweder alle Oktaederlücken durch Natrium oder geordnet 1/4 der Tetraederlücken durch Mangan besetzt.
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  • 283
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    Zeitschrift für anorganische Chemie 623 (1997), S. 1201-1202 
    ISSN: 0044-2313
    Keywords: Cobalt(II) complex ; 1,2-dimethyl-5-nitro-imidazole ligand ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and Crystal Structure of Bis(1,2-dimetyl-5-nitro-imidazole)dichlorocobalt(II)Bis(1,2-dimethyl-5-nitro-imidazol)dichlorocobalt(II) was obtained by reaction of CoCl2 · 6 H2O with 1,2-dimethyl-5-nitro-imidazole in methanol. The compound forms blue crystals which were characterized by IR and UV-vis spectroscopy and by an X-ray crystal structure determination. Co(C5H7N3O2)2Cl2: tetragonal, space group I42d, Z = 8, a = 1142.1(1) pm, c = 2577.3(2) pm. R = 0.036 for 670 independent reflexions. The Co atom is tetrahedrally surrounded by two chlorine and two N atoms at distances of 222.8(2) and 203.5(4) pm.
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  • 284
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    Zeitschrift für anorganische Chemie 623 (1997), S. 1203-1204 
    ISSN: 0044-2313
    Keywords: Ytterbium Complex ; Amido Compound ; Crystal Structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: [Yb3OBr4{N(SiMe3)2}3(THF)3], an Amido Complex of Ytterbium with a Clusterlike StructureThe title compound has been prepared from YbBr3 and NaN(SiMe3)2 in THF suspension, forming yellow single crystals from hexane solutions which were characterized by a crystal structure determination. Space group P1, Z = 2, lattice dimensions at -100°C: a = 1085.4(1), b = 1410.2(1), c = 1912.0(1) pm; α = 78.62(1)°, β = 80.61(1)°, γ = 73.45(1)°, R = 0.025.In the molecular structure of [Yb3OBr4{N(SiMe3)2}3(THF)3] the three ytterbium atoms together with the μ3-oxygen atom and a μ3-bromine atom form a distorted trigonal bipyramid. In addition, three μ2-Br atoms coordinate the Yb atoms in the equatorial plane, whereas the THF molecules and the N(SiMe3)2- ligands are terminally coordinated, thus forming a distorted octahedrally surrounding of the Yb atoms.
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  • 285
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    Zeitschrift für anorganische Chemie 623 (1997), S. 1205-1207 
    ISSN: 0044-2313
    Keywords: Amine Alcohol Ligands ; Binuclear Complexes ; Gadolinium Complexes ; Magnetic Properties ; Schiff Base Ligands ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and Structure of a Binuclear Gadolinium(III) Complex: Magnetic Exchange Interactions in Alkoxy Bridged Lanthanide ComplexesThe Schiff Base ligand N-salicylidene-2-(bis-(2-hydroxyethyl)amino)ethylamine (H3sabhea) reacts with Gd(NO3)3 · 6 H2O in methanol solution to yield the alkoxy bridged binuclear gadolinium(III) complex [{Gd(Hsabhea)(NO3)}2] · 2MeOH (1). 1 crystallizes in the monoclinic space group P21/c with a = 1014.8(2), b = 2059.2(4), c = 867.5(2) pm, β = 106.72(2)°, and Z = 2. The two gadolinium atoms are bridged by two alkoxide oxygen atoms with angles of 107.60(11)° at the oxygen bridgeheads and a Gd—Gd separation of 376.43(7) pm. A variable-temperature magnetic susceptibility study (2 to 280 K) of 1 revealed an antiferromagnetic coupling between the Gd(III) ions with J = -0.198 cm-1 (g = 1.975).
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  • 286
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    Zeitschrift für anorganische Chemie 623 (1997), S. 1163-1167 
    ISSN: 0044-2313
    Keywords: Titanium-Aluminium Alkoxide ; Aluminium Titanate (Tialite) ; Ceramics Precursor ; X-Ray Structure Determination ; 1H/13C-NMR (2 D) ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Structural Characterization of a Novel Titanium-Aluminium AlkoxideThe novel Ti-Al-Alkoxide TiAl2(OiPr)10, was synthesized from aluminium turnings and titanium tetraisopropoxide in 2-propanol and isolated by subsequent fractionating distillation. Colourless prismatic crystals precipitated after 24 h at 20°C from the main fraction. They proved very moisture sensitive. The compound crystallizes in the monoclinc space group C2/c (no. 15) with a = 2303.1(4), b = 1097.2(3), c = 1685.0(3) pm, β = 104.32(1)° and Z = 4. The molecular structure exhibits a bent Al-Ti-Al′ unit, in which Al shows tetrahedral, but Ti octahedral1 coordination. The polyhedra are connected via cis-edges of the octahedron. The structure of the compound in solution was determined by NMR spectroscopy (1H, 13C, COSY) and proved to be identical to the structure in the solid state.
    Notes: Das neue Ti-Al-Alkoxid TiAl2(OiPr)10 wurde durch Umsetzung von Al-Spänen mit Titantetraisopropoxid in Isopropanol und anschließender fraktionierender Destillation dargestellt. Die nach 24 h bei 20°C aus der Hauptfraktion gebildeten farblosen, prismatischen Kristalle sind sehr hydrolyseempfindlich. Die Kristallstruktur konnte bei -83°C bestimmt werden: monokline Raumgruppe C2/c (Nr. 15) mit a = 2303,1(4), b = 1097,2(3), c = 1685,0(3) pm, β = 104,32(1)° und Z = 4. Die Molekülstruktur besteht aus einer gewinkelten Al-Ti-Al′-Einheit, in der Al tetraedrisch und Ti oktaedrisch koordiniert sind. Die verknüpfenden Kanten am Ti-Oktaeder sind cis angeordnet. Die Struktur der Verbindung in Lösung wurde NMR-spektroskopisch (1H, 13C, COSY) ermittelt und stimmt mit der Struktur im Einkristall überein.
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    Zeitschrift für anorganische Chemie 623 (1997), S. 1168-1174 
    ISSN: 0044-2313
    Keywords: Sulfoximide ; Sulfoximidium Salts ; Structure ; Hydrogenbonding ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Sulfoximide and Sulfoximidium Salts - Structures and Hydrogen BondingIn the solid state dimethylsulfoximide (1) (orthorhombic; space group Pbca; a = 577.8, b = 931.2 and c = 1645.6 pm) makes intermolecular N—H ≡ N hydrogen bonds. The hydrogen halide salts (CH3)2S(O)NH2+Hal- ((2), Hal-=Cl-; (4), Hal-=Br-) reacts with metal halides to yield (CH3)2S(O)NH2+MHalyn- with the complex anions ((5), MHalyn-=SbCl4-; (6), MHalyn-=SbCl52-; (7), MHalyn-=SbCl6-; (8), MHalyn-=SbBr52-; (9), MHalyn-=AlCl4-). 2 crystallizes from ethanol (96%) as [(CH3)2S(O)NH2+Cl-]2 · H2O (3). The structures of 3 (monoclinic; space group P21/c; a = 917.0, b = 1344.7, c = 1080.8 pm and β = 103.8°; Z = 10), 4 (orthorhombic; space group Pbcn; a = 1028.9, b = 1132.6, c = 1074.1 pm; Z = 8) and 6 (monoclinic; space group C2/c; a = 2041.1, b = 1101.4, c = 3365.6 pm and β = 153.8°; Z = 8) are determined by X-ray analysis. In 6 Sb is coordinated in a distorted octahedra by 6 Cl in three short (mean 245,5 pm; SbCl3) and three long distances (291 to 299 pm; Cl-). Two of the chloride ions connect the Sb atoms to infinite Sb … Cl … Sb chains. Except for 7 and 9 there are bridges between the NH2 groups and the halide ions. The NH valence vibrations are discussed in view of hydrogen bonding.
    Notes: Im festen Dimethylsulfoximid (1) (orthorhombisch; Raumgruppe Pbca; a = 577,8, b = 931,2 und c = 1645,6 pm) sind zwischen den Imidgruppen N—H … N-Brückenbindungen ausgebildet. Die mit HHal darstellbaren Salze (CH3)2S(O)NH2+Hal- ((2), Hal-=Cl-; (4), Hal-=Br-) reagieren mit MHalx zu (CH3)2S(O)NH2+MHalyn- ((5), MHalyn-=SbCl4-; (6), MHalyn-=SbCl52-; (7), MHalyn-=SbCl6-; (8), MHalyn-=SbBr52-; (9), MHalyn-=AlCl4-). 2 kristallisiert aus 96% Ethanol als [(CH3)2S(O)NH2+Cl-]2 · H2O (3). Die Strukturen von 3 (monoklin; Raumgruppe P21/c; a = 917,0, b = 1344,7, c = 1080,8 pm und β = 103,8°; Z = 10), 4 (orthorhombisch; Raumgruppe Pbcn; a = 1028,9, b = 1132,6, c = 1074,1 pm; Z = 8) und 6 (monoklin; Raumgruppe C2/c; a = 2041,1, b = 1101,4, c = 3365.6 pm und β = 153,8°; Z = 8) wurden bestimmt. In 6 ist Sb verzerrt oktaedrisch von 6 Cl in drei kurzen (im Mittel 245,5 pm; SbCl3) und drei langen Abständen (291 bis 299 pm; Cl-) umgeben. Zwei der lang gebundenen Cl-Ionen verknüpfen die Sb-Atome zu unendlichen Sb … Cl … Sb-Ketten. Die NH2-Gruppen der Kationen bilden außer in 7 und in 9 H—Brückenbindungen zu den Halogenidionen. Die NH-Valenzschwingungen werden im Hinblick auf die Wasserstoffbrückenbindungen diskutiert.
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    Zeitschrift für anorganische Chemie 623 (1997), S. 1183-1189 
    ISSN: 0044-2313
    Keywords: Tris(perfluoroalkyl) arsenic and antimony ; tris(pentafluoroethyl) arsenic and antimony(V) halides ; synthesis ; NMR ; mass spectra ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparations and Properties of Tris(perfluoroalkyl) Arsenic and Antimony(III, V) CompoundsAs(Rf)3 and Sb(Rf)3 (Rf=C2F5, C4F9, C6F13) are prepared in good yields by the polar reactions of AsCl3 and SbCl3 with bis(perfluoroalkyl) cadmium compounds as colourless liquids or solids. The oxidation of As(C2F5)3 and Sb(C2F5)3 with XeF2 gives the difluorides M(C2F5)3F2 (M=As, Sb). As(C2F5)3Cl2 is prepared by chlorination of As(C2F5)3 in the presence of AlCl3, while Sb(C2F5)3Cl2 is formed in the reaction of Sb(C2F5)3F2 with (CH3)3SiCl. During the reaction of M(C2F5)3F2 with (CH3)3SiBr 19F-NMR spectroscopic evidence is found for M(C2F5)3 Br2. The thermal decompositions of M(C2F5)3F2 mainly yield C4F10 and M(C2F5)F2, while the thermal decompositions of M(C2F5)3Cl2 yield M(C2F5)2Cl and C2F5Cl. The properties and spectroscopic data of the new compounds are described.
    Notes: As(Rf)3 und Sb(Rf)3 (Rf=C2F5, C4F9, C6F13) werden durch Umsetzungen von AsCl3 und SbCl3 mit Bis(perfluoralkyl)cadmium-Verbindungen unter polaren Bedingungen in guten Ausbeuten als farblose Flüssigkeiten bzw. Festkörper dargestellt. Durch Oxidation von As(C2F5)3 und Sb(C2F5)3 mit XeF2 entstehen die Difluoride M(C2F5)3F2 (M=As, Sb). Die Darstellung von As(C2F5)3Cl2 gelingt durch Chlorierung von As(C2F5)3 in Gegenwart von AlCl3; die Darstellung von Sb(C2F5)3Cl2 durch Reaktion von Sb(C2F5)3F2 mit (CH3)3SiCl. Die Dibromide M(C2F5)3Br2 sind nur 19F-NMR-spektroskopisch bei der Reaktion von M(C2F5)3F2 mit (CH3)3SiBr nachweisbar. Bei der thermischen Zersetzung von M(C2F5)3F2 entstehen hauptsächlich C4F10 und M(C2F5)F2, während die thermische Zersetzung von M(C2F5)3Cl2 unter Bildung von M(C2F5)2Cl und C2F5Cl verläuft. Eigenschaften und spektroskopische Daten der neuen Verbindungen werden beschrieben.
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    Zeitschrift für anorganische Chemie 623 (1997) 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 290
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    Zeitschrift für anorganische Chemie 623 (1997), S. 1190-1200 
    ISSN: 0044-2313
    Keywords: Phase investigation ; chemical transport reactions ; zinc molybdate ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the System Zn/Mo/O. II. Chemical Transport of Ternary Zinc MolybdatesThe Chemical Transport is a method for preparation of phasepure multinary compounds with defined composition. We report about the possibilities to transport ternary compounds of the Zn/Mo/O system using Cl2, HCl, Br2, HBr, and I2 as an agent. The influence of the solid-gas equilibria on the compositions of solids, the transport direction, and the rate is showed.
    Notes: Der Chemische Transport ermöglicht eine gezielte phasenreine Darstellung von mehrkomponentigen Verbindungen mit definierter Zusammensetzung. Für das System Zn/Mo/O wird über die Möglichkeiten des Chemischen Transports der ternären Phasen mit den Transportmitteln Cl2, HCl, Br2, HBr und I2 berichtet. Dabei wird der Einfluß der Bodenkörper-Gasphase-Gleichgewichte auf die Bodenkörperzusammensetzungen, die Transportrichtung und Transportraten gezeigt.
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  • 291
    ISSN: 0044-2313
    Keywords: Bis(dimesy1amido-O)tetraaquametal(II) complexes ; bis(dimesy1amido-O)tetrapyridinemetal(II) complexes ; synthesis ; X-ray structure; isotypic series ; Jahn-Teller distortion ; O—H…O, O—H…N and C—H…O hydrogen bonds ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Polysulfonylamines. LXXXIV. Isotypic Structures in the Dimesylamide Complex Series [M(H2O)4{(CH3SO2)2N}2] (M=Mg, Ca, Ni, Cu, Zn, Cd) and [M(py)4{(CH3SO2)2N}2] (M=Ni, Cu, Zn, Cd)The crystal structures of the trans-octahedral complexes [M(H2O)4{(CH3SO2)2N}2] (M=Ca, Cd), in which the dimesylamide anion acts as a monodentate O-ligand and a tetrafunctional hydrogen bond acceptor, were determined by low-temperature X-ray diffraction. Both belong to an isotypic series (triclinic, space group P1, Z = 1) that had previously been characterized for M=Mg, Ni, Cu and Zn (Z. Anorg. Allg. Chem. 1996, 622, 1065). In this structure there exists an extended network of strong hydrogen bonds which is probably the underlying reason why the structure type surprisingly persists across the whole series. To support this explanation by indirect evidence from comparison with suitable structures devoid of strong hydrogen bonding, the analogous trans-octahedral complexes [M(py)4{(CH3SO2)2N}2] (M=Mn, Co, Ni, Cu, Zn, Cd) were prepared by treating M[(CH3SO2)2N]2 with pyridine, and the crystal structures of the Ni, Cu, Zn and Cd compounds were studied by low-temperature X-ray crystallography. As anticipated, the four pyridine complexes do not form an isotypic series but instead two isotypic pairs consisting of the Ni and Zn compounds (monoclinic, space group P21/n, Z =2) and of the Cu and Cd complexes (triclinic, space group P1, Z = 1). All molecules of the aqua and the pyridine complexes display crystallographic centrosymmetry. In the hydrates, the mean M—OH2 and the M—O(anion) distances are 232.6 and 232.7 pm for M = Ca, 225.5 and 230.3 pm für M = Cd. The mean M—N and the M—O(anion) bond lengths of the pyridine species amount to 211.8 and 213.1 pm for M = Ni, 217.0 and 218.5 pm for M = Zn, 232.8 and 234.4 pm for M = Cd; the corresponding values for the severely Jahn-Teller distorted Cu complex are 203.6 and 254.5 pm. In the crystals of the pyridine complexes, each methyl group is connected through a weak C—H…O bond to a sulfonyl oxygen atom of an adjacent molecule.
    Notes: Die Kristallstrukturen der trans-oktaedrischen Komplexe [M(H2O)4{(CH3SO2)2N}2] (M=Ca, Cd), in denen das Dimesylamid-Anion als einzähniger O-Ligand und tetrafunktioneller Wasserstoffbrücken-Akzeptor wirkt, wurden durch Tieftemperatur-Röntgenbeugung ermittelt. Beide gehören zu einer isotypen Reihe (triklin, Raumgruppe P1, Z = 1), die zuvor für M=Mg, Ni, Cu und Zn charakterisiert worden war (Z. Anorg. Allg. Chem. 1996, 622, 1065). Hauptursache für die überraschende Persistenz der Isotypie in der gesamten Reihe ist vermutlich das in der Struktur auftretende hochorganisierte Netzwerk aus starken intermolekularen Wasserstoffbrücken. Um diese Annahme durch indirekte Evidenz an vergleichbaren Strukturen ohne starke H-Brücken zu überprüfen, wurden die analogen trans-oktaedrischen Komplexe [M(py)4{(CH3SO2)2N}2] (M=Mn, Co, Ni, Cu, Zn, Cd) aus M[(CH3SO2)2N]2 und Pyridin dargestellt und die Vertreter mit M=Ni, Cu, Zn und Cd durch Tieftemperatur-Röntgenbeugung untersucht. Der Erwartung entsprechend bilden die vier Pyridin-Komplexe keine isotype Reihe, aber zwei isotype Paare, die aus der Ni- und der Zn- Verbindung (monoklin, Raumgruppe P21/n, Z = 2) bzw, dem Cu- und dem Cd-Komplex (triklin, Raumgruppe P1, Z = 1) bestehen. Sämtliche Moleküle besitzen kristallographische Inversionssymmetrie. Die Mittelwerte der M—OH2- und die M—O(Anion)-Abstände in den Wasser-Komplexen betragen 232,6 und 232,7 pm für M=Ca, 225,5 und 230,3 pm für M=Cd. In den Pyridin-Komplexen sind die mittleren M—N- und die M—O(Anion)-Bindungslängen 211,8 und 213,1 pm für M=Ni, 217,0 und 218,5 pm für M=Zn, 232,8 und 234,4 pm für M=Cd sowie 203,6 und 254,5 pm für den eine erhebliche Jahn-Teller-Verzerrung aufweisenden Cu-Komplex. In den Kristallen der Pyridin-Komplexe ist jede Methylgruppe über eine schwache C—H … O-Wechselwirkung mit einem Sulfonyl-Sauerstoffatom eines Nachbarmoleküls verknüpft.
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    Zeitschrift für anorganische Chemie 623 (1997), S. 1475-1482 
    ISSN: 0044-2313
    Keywords: Lithiumhydridosiloxysilylamides ; reaction behaviour ; N-silylation ; Si—O bond splitting ; cyclodisilazanes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Lithium Hydridosiloxysilylamides - Reactions in n-Octane and Tetrahydrofuran in Presence of ChlorotrimethylsilaneThe hydrido-siloxy-silylamino-silanes (Me3SiO)HSiMe(NHSiMe3) 1, (Me3SiO)HSi(NHSiMe3)2 2 and (Me3SiO)2HSi(NHSiMe3) 3 were prepared by coammonolysis of the chlorosiloxysilanes (Me3SiO)HSiMeCl and (Me3SiO)3-nHSiCln (n = 1, 2) with chlorotrimethylsilane. The reaction behaviour of lithiated compounds 1, 2 and 3 has been investigated in n-octane and tetrahydrofuran (THF) in presence of chlorotrimethylsilane.
    Notes: Durch Koammonolyse der Chlorsiloxysilane (Me3SiO)HSiMeCl und (Me3SiO)3-nHSiCln (n = 1, 2) mit Chlortrimethylsilan wurden die Hydrido-siloxy-silylamino-silane (Me3SiO)HSiMe(NHSiMe3) 1, (Me3SiO)HSi(NHSiMe3)2 2 und (Me3SiO)2HSi(NHSiMe3) 3 dargestellt und das Reaktionsverhalten der lithiierten Verbindungen 1, 2 und 3 in n-Octan und Tetrahydrofuran (THF) in Gegenwart von Chlortrimethylsilan untersucht.Sowohl das Monoamid (Me3SiO)HSiMe(NLiSiMe3) als auch das Diamid (Me3SiO)HSi(NLiSiMe3)2 reagieren unter N-Silylierung zu N-Substitutionsprodukten und unter Si—O-Bindungsspaltung und LiOSiMe3-Eliminierung zu Cyclodisilazanen, wobei THF die N-Silylierung, n-Octan die Bildung von Cyclodisilazanen begünstigt. Das Monoamid ergibt in n-Octan (Me3SiO)HSiMe[N(SiMe3)2] 4, [Me(H)Si-NSiMe3]2 5 (Hauptprodukt) und 6, in THF 4 als Hauptprodukt und 5. Aus dem Diamid werden in THF (Me3SiO)HSi[N(SiMe3)2](NHSiMe3) 7, bevorzugt (Me3SiO)HSi[N(SiMe3)2]2 8, [(Me3SiNH)HSi—NSiMe3]2 9 und 10 gebildet, in n-Octan 7, bevorzugt 9 und 10.Hauptprodukt der Reaktion des Amids (Me3SiO)2HSi(NLiSiMe3) in THF und n-Octan ist das N-Silylierungsprodukt (Me3SiO)2HSiN(SiMe3)2 11.Eine Reaktion unter Beteiligung der Si—H-Gruppe wird nur im Falle von (Me3SiO)HSiMe(NLiSiMe3) beobachtet, Produkt dieser Reaktion ist 6.The monoamide (Me3SiO)HSiMe(NLiSiMe3) and the diamide (Me3SiO)HSi(NLiSiMe3)2 react under N-silylation to N-substitution products and under Si—O-bond splitting and LiOSiMe3-elimination to cyclodisilazanes in n-octane as well as in THF. The favour reaction is in THF the N-silylation, in n-octane the formation of cyclodisilazanes. The monoamide gives in n-octane (Me3SiO)HSiMe[N(SiMe3)2] 4, [Me(H)Si-NSiMe3]2 5 (main product) and 6, in THF as main product 4 and 5. The diamide reacts in THF to give (Me3SiO)HSi[N(SiMe3)2](NHSiMe3) 7, mainly (Me3SiO)HSi[N(SiMe3)2]2 8, [(Me3SiNH)HSi—NSiMe3]2 9 and 10, in n-octane 7, mainly 9 and 10.The N-silylation product (Me3SiO)2HSiN(SiMe3)2 11 is the main product of the reaction of (Me3SiO)2HSi(NLiSiMe3) in THF and in n-octane.A reaction with participation of the Si-H group is only observed in the case of (Me3SiO)HSiMe(NLiSiMe3). 6 is the product of this reaction.
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  • 293
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1489-1491 
    ISSN: 0044-2313
    Keywords: 2,9-{N,N′-(2-aminopyridine)}octahydro-closo-decaborate(2-) ; Crystal Structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Crystal Structure of [P(C6H5)4][2,9-{N,N′-(2-NH—(C5H4N))}B10H8][N(C4H9)4]2[B10H10] reacts with 2-aminopyridine forming a product mixture from which [2,9-{N,N′-(2-NH—(C5H4N))}B10H8]- can be isolated by ion exchange chromatography on diethylaminoethyl(DEAE) cellulose. The crystal structure of [P(C6H5)4][2,9-{N,N′-(2-NH—(C5H4N))}B10H8] (triclinic, space group P1, a = 10.1103(9), b = 11.5665(9), c = 14.877(2) Å, α = 102.600(8), β = 107.567(8) und γ = 96.487(7)°, Z = 2) reveals the bonding of 2-NH2-(C5H4N) via both N atoms to vicinal B atoms of the two square planes of the B10 cluster (B2—N1 = 1,541(7) und B9—N2 = 1.505(7) Å) forming a five-membered ring.
    Notes: [N(C4H9)4]2[B10H10] reagiert mit 2-Aminopyridin unter Bildung eines Produktgemisches, aus dem durch Ionenaustauschchromatographie an Diethylaminoethyl(DEAE)-Cellulose [2,9-{N,N′-(2-NH—(C5H4N))}B10H8]- isoliert werden kann. Die Röntgenstrukturanalyse an [P(C6H5)4][2,9-{N,N′-(2-NH—(C5H4N))}B10H8] (triklin, Raumgruppe P1, a = 10,1103(9), b = 11,5665(9), c = 14,877(2) Å, α = 102,600(8), β = 107,567(8) und γ = 96,487(7)°, Z = 2) beweist, daß 2-NH2-(C5H4N) über beide N-Atome an benachbarte B-Atome der beiden quadratischen Ebenen des B10-Clusters (B2—N1 = 1,541(7) und B9—N2 = 1,505(7) Å) unter Ausbildung eines Fünfringes gebunden ist.
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  • 294
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    Zeitschrift für anorganische Chemie 623 (1997), S. 1493-1495 
    ISSN: 0044-2313
    Keywords: Synthesis ; Crystal structure ; Crown ether ; Lanthanides ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: [La2I2(OH)2(dibenzo-18-crown-6)2]I(I3), a Cationic Dimeric in-cavity Complex with Iodide and Triiodide as AnionsSingle crystals of [La2I2(OH)2(dibenzo-18-crown-6)2]I(I3) are obtained from the reaction of LaI3 and dibenzo-18-crown-6 in acetonitrile. The crystal structure monoclinic, C2/m, Z = 4, T = 293 [100] K, a = 2179(3) [2162.3(3)], b = 1070.3(3) [1069.6(1)], c = 1118.2(3) [1110.6(1)] pm, β = 93.1(1) [92.83(1)]°, R1 = 0.0601 [0.0411], wR2 = 0.1449 [0.1014] contains hydroxide-bridged cationic dimers and iodide as well as triiodide as anions.
    Additional Material: 2 Ill.
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  • 295
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1499-1500 
    ISSN: 0044-2313
    Keywords: Methylindium Compound ; Heterocubane ; Synthesis ; X-ray Structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The X-Ray Structure Determination of tert-Butylimido Methylindane, [CH3In—NC(CH3)3]4The reaction of MeInCl2 with LiN(H)tBu in a 1 : 2 molar ratio forms [MeIn—NtBu]4 in high yield, lithium chloride, and the free amine H2NtBu. The crystal structure of the imidomethylindane with a cubic In4N4 skeleton has been determined.
    Additional Material: 1 Ill.
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  • 296
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1503-1505 
    ISSN: 0044-2313
    Keywords: Ditetraammine lithium tetraphenyldistannide ; synthesis ; single-crystals ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Tetraammine Lithium Cations Stabilizing Phenylsubstituted Zintl-Anions: The Compound [Li(NH3)4]2[Sn2Ph4]Ruby-red, brittle single crystals of [Li(NH3)4]2[Sn2Ph4] were synthesized by the reaction of diphenyltin dichloride and metallic lithium in liquid ammonia at -35°C. The structure was determined from X-ray singlecrystal diffractometer data: Space group, P1, Z = 1, a = 9.462(2) Å, b = 9.727(2) Å, c = 11.232(2) Å, α = 66.22(3)°, β = 85.78(3)°, γ = 61.83(3)°, R1 (F02 ≥ 4σF02) = 5.13%, wR2 (F02 ≥ 4σF02) = 10.5%, N(F02 ≥ 4σF02) = 779, N(Var.) = 163.The compound contains to Sb2Ph4 isosteric centres [Sn2Ph4]2- as anions which are connected to rods by lithium cations in distorted tetrahedral coordination by ammonia. These rods are arranged parallel to one another in the b,c-plane, but stacked along [100].
    Additional Material: 2 Ill.
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  • 297
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    Zeitschrift für anorganische Chemie 623 (1997), S. 1525-1528 
    ISSN: 0044-2313
    Keywords: Ternary sodium chlorides ; Holmium ; Erbium ; Phase diagrams ; Thermodynamic properties ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Ternary Chlorides in the Systems NaCl/HoCl3 and NaCl/ErCl3Phase diagrams of the systems NaCl/HoCl3 and NaCl/ErCl3 were determined by means of DTA and high-temperature XRD. There exist compounds Na3LnCl6, NaLnCl4 (Ln = Ho, Er) and NaHo2Cl7. NaHoCl4 undergoes a phase transition at 374°C from the NaGdCl4- to the NaErCl4- type of structure. The thermodynamic functions for the formation of the compounds from NaCl and LnCl3 were determined by solution calorimetry and e.m.f. measurements in galvanic cells for solid electrolytes. The compounds NaLnCl4 are the most stable ones.
    Notes: Die Zustandsdiagramme der Systeme NaCl/HoCl3 und NaCl/ErCl3 wurden mittels DTA und Hochtemperatur-Guinieraufnahmen untersucht. Es existieren Verbindungen Na3LnCl6 und NaLnCl4 (Ln = Ho, Er) sowie NaHo2Cl7. NaHoCl4 wandelt sich bei 374° vom NaGdCl4- in den NaErCl4-Typ um. Mittels Lösungskalorimetrie und EMK-Messungen in galvanischen Feststoffzellen wurden die thermodynamischen Funktionen der ternären Chloride bezüglich der Bildung aus NaCl und LnCl3 bestimmt. Die Verbindungen NaLnCl4 weisen die größte Stabilität auf.
    Additional Material: 2 Ill.
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  • 298
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    Zeitschrift für anorganische Chemie 623 (1997), S. 1535-1541 
    ISSN: 0044-2313
    Keywords: Bismuth platinum iodide ; subhalide ; crystal structure ; pseudo-symmetry ; stacking faults ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Bi13Pt3I7: A Subiodide with a Pseudo-Symmetric Layer StructureThe reaction of PtI2 with Bi and BiI at 630 K yields black, lustrous, air insensitive crystals of the subiodide Bi13Pt3I7. The layered crystal structure (triclinic, C1, a = 1581.0(2) pm, b = 912.6(1) pm, c = 2149.6(6) pm, α = 90.03(2)°, β = 96.96(2)°, γ = 90.11(1)°, V = 3078.6 · 106 pm3) contains edge-sharing [PtBi8/2] cubes, which form nets of Kagomé type. Iodine atoms fill the hexagonal-prismatic voids therein. These ∞2[(PtBi8/2)3I] layers are alternately separated by layers of iodine atoms or ∞1[BiI4-] zigzag-chains. The marked pseudo-symmetry of the structure favours stacking faults, which cause streaks of diffuse scattering in the diffraction pattern.
    Notes: Aus der Reaktion von PtI2 mit Bi und BiI bei 630 K erhält man schwarze, metallisch glänzende und luftbeständige Kristalle des Subiodids Bi13Pt3I7. In der schichtartig aufgebauten Kristallstruktur (triklin, C1, a = 1581,0(2) pm, b = 912,6(1) pm, c = 2149,6(6) pm, α = 90,03(2)°, β = 96,96(2)°, γ = 90,11(1)°, V = 3078,6 · 106 pm3) liegen Kagomé-Netze aus kantenverknüpften [PtBi8/2]-Würfeln vor, deren hexagonal-prismatische Lücken mit Iodatomen gefüllt sind. Diese ∞2[(PtBi8/2)3I]-Schichten sind abwechselnd durch eine Lage von Iodatomen oder eine Schicht aus parallel angeordneten ∞1[BiI4-]-Zickzackketten getrennt. Die in der Struktur stark ausgeprägte Pseudosymmetrie begünstigt Stapelfehler, welche sich auch in diffusen Streifen im Beugungsbild äußern.
    Additional Material: 6 Ill.
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  • 299
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1287-1289 
    ISSN: 0044-2313
    Keywords: Calcium hexahydroxodizincate dihydrate ; synthesis ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Crystal Structure of CaZn2(OH)6 · 2 H2OThe electrochemical oxidation of zinc in a zinc/iron-pair leads in an aqueous NH3 solution of calciumhydroxide at room temperature to colourless crystals of CaZn2(OH)6 · 2 H2O. The X-ray structure determination was now successful including all hydrogen positions.P21/c, Z = 2, a = 6.372(1) Å, b = 10.940(2) Å, c = 5.749(2) Å, β = 101.94(2)° N(F2o ≥ 3σF2o) = 809, N(Var.) = 69, R/RW = 0.011/0.012The compound CaZn2(OH)6 · 2H2O contains Zn2+ in tetrahedral coordination by OH- and Ca2+ in octahedral coordination by four OH- and two H2O. The tetrahedra around Zn2+ form corner sharing chains, three-dimensionally linked by isolated polyhedra around Ca2+. Weak hydrogen bridge bonds result between H2O as donor and OH-.
    Notes: Die elektrochemische Oxidation von Zink in einem Zink/Eisen-Paar führt in einer wäßrigen NH3-Lösung von Calciumhydroxid bei Raumtemperatur zu farblosen Kristallen von CaZn2(OH)6 · 2 H2O. An ihnen wurde röntgenographisch die Struktur jetzt einschließlich aller H-Lagen bestimmt.P21/c, Z = 2, a = 6,372(1) Å, b = 10,940(2) Å, c = 5,749(2) Å, β = 101,94(2)° Z(F2o ≥ 3σF2o) = 809, Z(Var.) = 69, R/RW = 0,011/0,012In CaZn2(OH)6 · 2 H2O ist Zn2+ tetraedrisch von OH- und Ca2+ oktaedrisch von vier OH- und zwei H2O umgeben. Die Tetraeder um Zn2+ bilden Ketten über gemeinsame Ecken, die durch voneinander isolierten Oktaedern um Ca2+ dreidimensional verknüpft werden. Es liegen schwache H-Brückenbindungen von H2O als Donator zu OH- vor.
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  • 300
    ISSN: 0044-2313
    Keywords: Pseudoelement compounds ; cyanamidonitrate ; copper(I) ; silver(I) ; platinum(II) ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Pseudoelement Compounds. XI. [1] Investigations on the Coordination Behaviour of Cyanamidonitrate [NO2NCN]-With the ionic, potentially ambidentate ligand cyanamidonitrate complexes of the types [MX(PPh3)3], [MX(PPh3)2]2 (M=CuI, AgI) and trans-[Pt(H)X(PPh3)2] (X-=[NO2NCN]-) are introduced. The new compounds are characterized by 1H NMR, 31P NMR, and IR spectroscopy. The crystal structures of [Cu(NO2NCN)(PPh3)2]2 and [Ag(NO2NCN)(PPh3)2]2 are reported. In the complexes [MX(PPh3)3] and trans-[Pt(H)X(PPh3)2] cyanamidonitrate is unidentately coordinated through the nitrile group end-on. In the dimeric complexes [MX(PPh3)2]2 the anion acts bidentately as a bridging ligand. Surprisingly, both coordinative bonds are formed through nitrogen atoms of the NCN group.
    Notes: Es werden mit dem ionischen, potentiell ambidenten Liganden Cyanamidonitrat Komplexe der Typen [MX(PPh3)3], [MX(PPh3)2]2 (M=CuI, AgI) sowie trans-[Pt(H)X(PPh3)2] (X-=[NO2NCN]-) vorgestellt. Die Verbindungen wurden 1H-NMR-, 31P-NMR- und IR-spektroskopisch charakterisiert. Für [Cu(NO2NCN)(PPh3)2]2 und [Ag(NO2NCN)(PPh3)2]2 liegen Kristallstrukturanalysen vor.Cyanamidonitrat wird in den Komplexen [MX(PPh3)3] und trans-[Pt(H)X(PPh3)2] einzähnig über das endständige N-Atom der Nitrilgruppe koordiniert. In den dimeren Komplexen [MX(PPh3)2]2 liegt das Anion als zweizähniger Brükkenligand vor. Überraschend werden beide koordinativen Bindungen über die Stickstoffatome der NCN-Gruppe ausgebildet.
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