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1.
The reaction between triphenylbismuth, hydrogen peroxide, and 3,4,5-trifluorobenzoic or pentafluorobenzoic acid (molar ratio 1 : 1 : 2, respectively) in ether gave triphenylbismuth bis(3,4,5-trifluorobenzoate) (I) and triphenylbismuth bis(pentafluorobenzoate) (II) in 74 and 89% yields, respectively. The structures of compounds I and II were established by X-ray diffraction. The Bi atoms have a distorted trigonal-bipyramidal coordination with acylate groups in the axial positions. The OBiO angles are 170.2(2)° and 171.5(2)° in I and II, respectively. The Bi–C(Ph)eq bond lengths vary in the range of 2.187(6)–2.204(5) Å, the Bi–O(acyl) lengths are 2.256(5) Å in I, and 2.281(5) and 2.318(5) Å in II. In the crystals I and II, the Bi and carbonyl O atoms are involved in intramolecular interactions (Bi···O(=C) 2.926(5)–3.176(5) Å), which increase the equatorial CBiC angles on the side of these contacts to 136.2(3)° and 138.6(2)° in I and II, respectively.  相似文献   
2.
Oxidation of pentaphenylantimony with atmospheric oxygen in toluene on heating gives -oxo-bis(tetraphenylantimony) (yield 63%). Its reaction with tetrafluorophthalic anhydride gives bis(tetraphenylantimony) tetrafluorophthalate (yield 94%). According to single-crystal X-ray diffraction data, the antimony atoms in the molecule of bis(tetraphenylantimony) tetrafluorophthalate have a distorted trigonal bipyramidal coordination with the following geometries: Sb-O bond lengths 2.357(3) and 2.283(3) Å, Sb-C bond lengths 2.108(4)-2.141(4) and 2.100(5)-2.158(4) Å, and CSbO angles 177.42(14)° and 176.18(14)°.  相似文献   
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4.
A comparative analysis has been made of the amounts of lipids and their fatty-acid compositions in the seeds of the lines of agenetic collection of cotton plants of the speciesGossypium hirsutum and their hybrids and the variety Tashkent-1. The results obtained on the fatty-acid compositions of some hybrids make it possible to recommend the use of individual lines of cotton plants as donors for improving the food-value indices of cottonseed oil.Institute of Chemsitry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 173–176, March–April, 1991.  相似文献   
5.
Recent advances in studies of bismuth(III) halide complexes (HBs) are reviewed concisely. New structural types of HBs and some of their physical properties that show the greatest promise for application and attract the greatest attention of researchers are discussed.  相似文献   
6.
A nickel complex-catalyzed hydrodefluorination of acet(pentafluoroanilide) with zinc in ionic liquids resulted in the corresponding 2,3,4,5-tetrafluoro, 3,4,5-trifluoro, and 3,4-difluoro derivatives. The influence of the ionic liquid nature and the reaction conditions on its selectivity were studied, a possibility of the multiple reuse of the ionic liquids as the reaction media was demonstrated.  相似文献   
7.
Journal of Structural Chemistry - Reactions of Bi2O3 solutions in 2M HCl with 3-methylpyridine and 4-iodopyridine result in the formation of binuclear Cat4[Bi2Cl10] complexes...  相似文献   
8.
The reaction of 3-bromobenzanthrone and 4-bromonaphthalic acid derivatives with a reduction system NiCl2-2,2′bipyridyl (or l,10-phenathroline)-Zn gives rise to compounds containing perylene fragment. Under similar conditions was established a possibility to transform substituted l.l′-binaphthyls into the corresponding perylene derivatives. The study was carried out under financial support of the State Research Center “NIOPIK” (grant no.528/93-1679).  相似文献   
9.
By a reaction of [BiX6]3– with salts of various N-alkylated pyridine derivatives in 2M HX (X = Cl, Br), (N-BzPy)4[Bi2X10] complexes (X = Cl (1), Br (2), (4-MePyH)4[Bi2Cl10] (3)) are obtained and structurally characterized.  相似文献   
10.
Adducts of cucurbit[6]uril with Ca2+ and trinuclear cluster chloroaquacomplexes (H9O4)2(H7O3)2[(Ca(H2O)5)2(C36H36N24O12)]Cl8·0.67H2O (1) and [(Ca(H2O)5)2(C36H36N24O12)]× [Mo3O2S2Cl6(H2O)3]2·13H2O (2) are obtained and structurally characterized. The structures of both compounds contain polymeric [Ca(H2O) n ]22 CB[6]∞ cations that form infinite columns; the space between them is filled with Cls- (1) and [Mo3O2S2Cl6(H2O)3]2s- (2). A new (H7O3)2(H5O2)× [Mo3S4Cl6.25Br0.25(H2O)2](C36H36N24O12)·CH2Cl2·6H2O complex (3) is also obtained and structurally characterized.  相似文献   
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