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961.
Nils Wiberg Wolfgang Niedermayer Hans‐Wolfram Lerner Michael Bolte 《无机化学与普通化学杂志》2001,627(5):1043-1047
Disupersilylsilanides M(SiHR*2)2 of Metals of the Zinc Group (M = Zn, Cd, Hg; R* = Si t Bu3): Syntheses, Characterization, and Structures Bis(disupersilyl)silylmetals M(SiHR )2 (R* = Supersilyl = SitBu3) with M = Zn, Cd, Hg are obtained in tetrahydrofuran/benzene/pentane by the reaction of NaSiHR with ZnCl2, CdI2, HgCl2 in the molar ratio 2 : 1. The compounds form colorless, in organic media soluble, not hydrolysis‐ and air‐sensitive crystals, the stabilities of which for thermolysis or photolysis decrease in the row Zn > Hg > Cd compound. According to X‐ray structure analyses, the compounds M(SiHR )2 are monomeric with a – to date not observed – non‐linear framework –M– (angle SiMSi for M(SiHR )2 with M = Zn/Cd/Hg 170.7/174.2/174.4°). 相似文献
962.
963.
964.
Wolfram Uhlig 《先进技术聚合物》1999,10(8):573-522
Novel poly(silylenemethylene)s have been prepared by the ring‐opening polymerization of 1,3‐disilacyclobutanes followed by a protodesilylation reaction with triflic acid. The silicon–aryl bond cleavage could be controlled by using different leaving groups, for instance phenyl‐ and para‐anisyl substituents. The reactions of the triflate derivatives with organomagnesium compounds, LiAlH4, amines or alcohols gave functional substituted poly(silylenemethylene)s. Hydrosilylation reactions or reductive coupling with potassium–graphite led to organosilicon network‐polymers, which may serve as suitable precursors for silicon carbide and Si/C/N‐based materials. The structures of the polymers were identified by nuclear magnetic resonance spectroscopy (29Si, 13C, 1H). Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
965.
Wolfram Koch 《Nachrichten aus der Chemie》1999,47(2):103-103
966.
967.
Wolfram Uhlig 《Journal of polymer science. Part A, Polymer chemistry》1998,36(5):725-735
Novel poly(silylenemethylenes) have been prepared by the ring-opening polymerization of 1,3-disilacyclobutanes followed by a protodesilylation reaction with triflic acid. The silicon–aryl bond cleavage could be controlled by using different leaving groups, for instance phenyl- and para-anisyl substituents. The reactions of the triflate derivatives with organomagnesium compounds, LiAlH4, amines, or alcohols gave functional substituted poly(silylenemethylenes). Hydrosilylation reactions or reductive coupling with potassium–graphite led to organosilicon network–polymers, which may serve as suitable precursors for silicon carbide and Si/C/N-based materials. The structures of the polymers were identified by NMR spectroscopy (29Si, 13C, 1H). © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 725–735, 1998 相似文献
968.
969.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献
970.
Paul Varava Tak Hin Wong Zhaowen Dong Anastasia Yu. Gitlina Andrzej Sienkiewicz Wolfram Feuerstein Rosario Scopelliti Farzaneh Fadaei-Tirani Kay Severin 《Angewandte Chemie (International ed. in English)》2023,62(25):e202303375
The head-to-tail dimerization of N-heterocyclic diazoolefins is described. The products of these formal (3+3) cycloaddition reactions are strongly reducing quinoidal tetrazines. Oxidation of the tetrazines occurs in a stepwise fashion, and we were able to isolate a stable radical cation and diamagnetic dications. The latter are also accessible by oxidative dimerization of diazoolefins. 相似文献