Copper(II)-Catalyzed Silylation of Activated Alkynes in Water: Diastereodivergent Access to E- or Z-β-Silyl-α,β-Unsaturated Carbonyl and Carboxyl Compounds

摘要

Copper(II)-catalyzed silylation of substituted alky-nylcarbonyl compounds was investigated. Through the activation of Me2PhSiBpin in water at room temperature and open atmosphere, vinylsilanes conjugated to carbonyl groups are synthesized in high yield. A surprising diastereodivergent access to olefin geometry was discovered using a silyl conjugate addition strategy: aldehydes and ketones were Z selective while esters and amides were exclusively transformed into the E products.