Generation of the α-Sulfinyl Carbenoid from α-Chloro Sulfoxides: A New Method for One-Carbon Homologation of Ketones to α-Sulfinyl Ketones

Abstract

Abstract Treatment of 1-chloroalkyl phenyl sulfoxides with a base gave carbenoids rather than free carbenes. The carbenoids were successfully used in a new method for homologation of ketones to α-sulfinyl ketones. Treatment of the carbanion of chloromethyl phenyl sulfoxide with ketones gave the adducts, α-chloro β-hydroxy sulfoxides, in nearly quantitative yields. The adducts were treated with excess lithium diisopropylamide to give one-carbon homologated α-sulfinyl ketones via α-sulfinyl β-oxido carbenoids in moderate to good yields. This type of reaction was found not to occur with the corresponding sulfones.