Highly stereoselective synthesis of para-substituted (E)-N-styrylcarbazoles via sequential silylative coupling–Hiyama coupling reaction
摘要:
A series of new para-substituted (E)-(N)-styrylcarbazoles, i.e., eight (E)-9-[2-(aryl)ethenyl]-9H-carbazoles (5-12) and 1,4-bis[(E)-2-(9H-carbazol-9-yl)vinyl]benzene (13), have been synthesized in high yield and stereoselectively by a sequential silylative coupling-Hiyama coupling reaction, i.e., coupling of commercially available 9-vinylcarbazole with vinyltriethoxysilane or divinyltetrame-thyldisiloxane in the presence of [RuHCl(CO)(PCy3)(2)] (1), followed by Pd (11) catalyzed cross-coupling with para- substituted iodobenzenes. The tandem procedure has facilitated the synthesis of 13. X-ray structures of the intermediate silylvinylcarbazole (4), as well as products 12 and 13 have been obtained. (c) 2006 Elsevier Ltd. All rights reserved.
Lewis Base Catalyzed Selective Chlorination of Monosilanes
作者:Alexander G. Sturm、Julia I. Schweizer、Lioba Meyer、Tobias Santowski、Norbert Auner、Max C. Holthausen
DOI:10.1002/chem.201803921
日期:2018.12.3
A preparatively facile, highly selective synthesis of bifunctional monosilanes R2SiHCl, RSiHCl2 and RSiH2Cl is reported. By chlorination of R2SiH2 and RSiH3 with concentrated HCl/ether solutions, the stepwise introduction of Si−Cl bonds is readily controlled by temperature and reaction time for a broad range of substrates. In a combined experimental and computational study, we establish a new mode
Reactions of diboron tetrahalides with some unsaturated organometallic compounds
作者:T.D. Coyle、J.J. Ritter
DOI:10.1016/s0022-328x(00)93848-8
日期:1968.5
Tetrachloro- and tetrafluorodiborane(4) add to the double bond in a number of vinyl derivatives of boron, carbon, silicon, germanium, and tin to form 1,2-bis(dihaloboryl)ethyl derivatives. Most of the compounds are stable in vacuo at temperatures in excess of 150°. Tetrachlorodiborane(4) undergoes addition considerably more readily than does tetrafluorodiborane(4). Relative rates of addition have been determined
Microwave spectrum of vinyl silane; structure, dipole moment and internal rotation of the silyl group
作者:Yoshiko Shiki、Akinori Hasegawa、Michiro Hayashi
DOI:10.1016/0022-2860(82)80005-7
日期:1982.2
Abstract Microwave spectra of vinyl silane and its twelve isotopically substituted species have been measured. The r s structure of the molecule has been determined from the observed moments of inertia. Dipole moments for the normal and SiD 3 CHCH 2 species are determined from Stark-effect measurements and the direction of the dipole moment in the molecule is discussed. From the A — E splittings of
An electron spin resonance study of 1-sila-allyl and 1,1-dimethyl-1-sila-allyl radicals
作者:Richard A. Jackson、Antonlos K. Zarkadis
DOI:10.1016/0040-4039(88)85199-2
日期:1988.1
Electronspinresonance spectra of 1-sila-allyl and 1,1-dimethyl-1-sila-allyl radicals have been obtained by y-irradiation of the parent organosilicon hydride in an adamantane matrix. The radicals show evidence of significant delocalization.
Infrared and Raman spectra, conformational stability, barriers to internal rotation, normal-coordinate calculations and vibrational assignments for vinyl silyl bromide
作者:Gamil A. Guirgis、Yasser E. Nashed、James R. Durig
DOI:10.1016/s1386-1425(99)00204-8
日期:2000.5
The infrared (3200-30 cm(-1) spectra of gaseous and solid, the Raman spectra (3200-30 cm(-1)) of the liquid and solid vinyl silyl bromide, CH2CHSiH2Br, have been recorded. Additionally, quantitative depolarization values have been obtained. Both the gauche and cis conformers have been identified in the fluid phases but only the gauche conformer remains in the solid. Variable temperature studies from