“Amphiphilic” Cleavage ofγ-Stannyl Ketones with ATPH/RLi: Application to Enone Fragmentation by the Conjugate Addition - Cleavage Sequence

Abstract

The use of a combined Lewis acid/base system consisting of aluminum tris(2,6-diphenylphenoxide) (ATPH) and MeLi has allowed the electrophilically activated nucleophilic ("amphiphilic") cleavage of C(alpha)-C(beta) bonds in gamma-stannyl ketones. Through combination with the conjugate addition of alpha-stannyl carbanion to enone, this approach constitutes a novel two-step conjugate addition - cleavage sequence that leads to functionalized ketones (see reaction).