Lewis Acid-Catalyzed Nucleophilic Substitutions of Propargylic and Allylic Silyl Ethers with Enol Silyl Ethers

Abstract

Nucleophilic reactions of various enol silyl ethers with carbocation species generated from propargyl silyl ethers by the action of a Lewis acid have been developed. The present method is highly useful for the introduction of allenic or enyne functionalities into the alpha-position of substituted ketones. [reaction--see text]