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71.
The first isocyanide ligated hexanuclear zirconium halide cluster is reported. The unoxidized [(Zr6Be)Cl12(CNXyl)6] (CNXyl = 2,6-dimethylphenyl isocyanide) was obtained from the solid state precursor K3Zr6Cl15Be by dissolution in CH3CN in the presence of CNXyl. The CNXyl ligands occupy all the axial positions on the cluster. The compound was recrystallized from CH2Cl2 and Et2O. [(Zr6Be)Cl12(CNXyl)6].2CH2Cl2 crystallizes in the space group
(#2) with a = 12.092(5) Å, b=12.728(5) Å, c = 14.102(8) Å, = 104.98(4)°, =107.11°, = 100.94°, V = 1919(2) Å3, Z = l, R = 11.3% and R
W
= 27.0%. For the bound isocyanide ligands, v
CN increases to 2140 cm–1. 相似文献
72.
α-Bromo benzolymethylene triphenylphosphorane 3 has been synthesized by the reaction of benzoylmethylene triphenylphosphorane 1 with N-bromosuccinimide in the yield of 87% and can react with aromatic aldehydes 4 to give α-bromochalcones 5 in good yields. 相似文献
73.
74.
Twenty-one new organogermanium compounds with the formulae Ph3GeCHR1CH2CONHNHC(X)NHR2 (1) (R1=H, Ph; = Ph, p-CH3Ph, O -CH3Ph, p-ClPh, COPh, X = S, O) and (R1 = H, Ph; R2 = Ph, p-CH3Ph, o-CH3Ph, p-ClPh; X=S, O) were synthesized and characterized by elemental analysis, 1H NMR, IR, MS and X-ray diffraction techniques. Compounds l were prepared by the reactions of Ph3GeCHR1CH2CONHNH2 with R2NCX in chloroform in 77-94% yields, and 2 were obtained by refluxing l with sodium hydroxide (8%) with yields of 55-94%. 相似文献
75.
76.
Christian R. Noe M. Knollmüller G. Steinbauer E. Wagner H. Kürner P. Ettmayer H. Völlenkle 《Monatshefte für Chemie / Chemical Monthly》1991,122(4):299-317
Summary Enantiomerically pure 1,2-diols bearing optionallysyn oranti configurated secondary hydroxylic groups are synthesized from acetal-protected cyanohydrins. After resolution of the diastereomers the cyanohydrins are converted into -alkoxy-ketones by Grignard-reaction followed by reduction using common chelating or non-chelating agents. Among others syntheses of enantiomerically pure pheromones,endo-Brevicomin,exo-Brevicomin and Dispalure are given as examples.
Prof. Dr. Hans Berbalk zum 70. Geburtstag gewidmet 相似文献
77.
U. M. Dzhemilev A. G. Ibragimov A. B. Morozov R. R. Muslukhov G. A. Tolstikov 《Russian Chemical Bulletin》1992,41(6):1089-1093
A new stereoselective method is developed for the synthesis of 1-chloro-, 1-alkoxy-, and 1-N,N-dialkylaminoalumino-cyclopentanes from -olefins, metallic magnesium, and aluminum halides (AlCl3, RO-AlCl2, R2N-AlCl2) in the presence of catalytic amounts of Cp2ZrCl2 (Cp=5-C5H5). The products from hydrolysis and deuterolysis of the Al-substituted 3,4-dialkylaluminocyclopentanes (ACP) have the threo configuration.For Communication 8, see [1].Institute of Organic Chemistry, Urals Branch, Russian Academy of Sciences, 450054 Ufa. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 6, pp. 1393–1397, June, 1992. 相似文献
78.
Yu. N. Belokon' 《Russian Chemical Bulletin》1992,41(5):868-884
The complexes of glycine, -alanine, and -alanine with (S)-[N-(N-benzylprolyl)amino] benzophenone formed by Ni(II) and Cu(II) ions and Schiff bases enter into different nucleophilic and electrophilic reactions with the formation of diastereoisomeric complexes which decompose into proteinogenic and nonproteinogenic L-amino acids with a high chemical yield and elevated optical purity (70–90%). Optically pure amino acids can be obtained from diastereoisomerically pure complexes after the complexes are separated by recrystallization of the mixture of diastereoisomeric complexes formed. A new type of interphase catalysts of C-alkylation of achiral Schiff bases was proposed. The catalysts are positively charged Ni(II) and Cu(II) complexes of Schiff bases of chiral diamines. In some cases, these complexes have a higher activity and capacity to execute asymmetric alkylation than traditional chiral interphase catalysts based on cinchonidine.Based on materials in the section report by Yu. N. Belokon' to the 7th European Symposium on Organic Chemistry, ESOC-7.A. N. Nesmeyanov Institute of Organoelemental Compounds, Russian Academy of Sciences, 117813 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 5, pp. 1106–1127, May, 1992. 相似文献
79.
绿色合成氧化剂高铁酸盐 总被引:13,自引:0,他引:13
高铁酸盐是绿色、无污染、高选择性和高活性的强氧化剂,其氧化性能比KMn04、O3和Cl还强,可以氧化醇类、含氮化合物、甚至烃类等有机化合物,高铁酸盐在有机物氧化合成中的应用具有很好的发展前景。本文介绍了有关高铁酸盐的制备方法、性质及有机物氧化合成方面的研究进展。 相似文献
80.
E. Luboch 《Journal of inclusion phenomena and macrocyclic chemistry》1996,26(4):253-268
A series of lipophilic derivatives of benzo-12-crown-4 and naphtho-12-crown-4 has been synthesized. The behavior of the prepared derivatives in membrane ion-selective electrodes has been studied. Selectivity changes dependent on the position and number of substituents have been observed. 相似文献