On the other hand, the addition reactions of 1-chlorovinyl p-tolyl sulfoxides derived from aldehydes with lithium acetylides directly gave conjugated enynes bearing a p-tolyl sulfinyl group at the 1-position through the 1,2-carbon–hydrogen insertion (1,2-CH insertion) reaction of the generated lithium carbenoid intermediates. These procedures provide a good way for the synthesis of multi-substituted
AbstractA variety of 2‐monosubstituted and 2,2‐disubstituted 1‐chlorovinyl p‐tolyl sulfoxides was synthesized through a one‐pot procedure by the Horner‐Wadsworth‐Emmons reaction of carbonyl compounds with [chloro(diethoxyphosphoryl)(p‐tolylsulfinyl)methyl]lithium, which was generated from diethyl chlorophosphate, chloromethyl p‐tolyl sulfoxide, and lithium diisopropylamide in advance. The in situ‐prepared sulfoxides were directly converted into alkynes via the sulfoxide/magnesium exchange reaction with i‐PrMgCl and the subsequent Fritsch‐Buttenberg‐Wiechell rearrangement of the resulting magnesium alkylidene carbenoids.