Stereoselective Preparation of Silyloxy-Alkenylcopper Species from Acylsilanes

Significance

Reactions using the migration of a silyl moiety from carbon to oxygen provide a promising method for the generation of new organo­metallic species. Here the authors report a new route for making functionalized alkenylcopper reagents, based on a Brook-type rearrangement of acylsilane enolates. The reaction of the resultant organocopper species with electrophiles like alkyl, allyl or aryl halides affords various silyl enol ethers, perfect regiochemistry and exclusively Z-configuration of the double bond. These silyl enone ethers are useful reactive intermediates. All reactions proceed in DMF within several minutes at ambient temperature.