A Simplified Preparation of Vinyl Sulfides, Selenides and Tellurides by a Wittig-Type Reaction
作者:Claudio C. Silveira、Mauro L. Begnini、Paula Boeck、Antonio L. Braga
DOI:10.1055/s-1997-1173
日期:1997.2
The preparation of several vinyl sulfides, selenides and tellurides by Wittig-type reaction in a one-pot procedure is described. The chalcogenyl triphenylphosphoranes 3 are formed "in situ" by the reaction of chloromethyl phenyl chalcogenide, potassium tert-butoxide and triphenylphosphine. Reaction of 3 with carbonyl compounds afford the vinyl chalcogenides 6-9 with preferential Z-configuration.
Desulfonylation of α-Methylthio-α,β-unsaturated Sulfones. A New Route to One Carbon Homologation of Aromatic Aldehydes
作者:Xian Huang、Han-Zhong Zhang
DOI:10.1055/s-1989-27143
日期:——
α-Methylthio-α,β-unsaturated sulfones 3 prepared from aromatic aldehydes 1 and sulfone 2 react with sodium hydrogen telluride in ethanol to undergo reductive desulfonylation to give vinyl sulfides 4 with certain extent of stereospecificity. A new route to one carbon homologation of aromatic aldehydes 1 to 5 is achieved by hydrolysis of 4 with titanium tetrachloride.