Asymmetric Induction on Copper(I) Chloride catalyzed 1,4‐addition of alkylmagnesium chlorides to α, β‐disubstituted (E)‐enoylsultams and subsequent protonation

Abstract

AbstractSuccessive treatment of conjugated N‐enoylsultams 2 with alkyl Grignard reagents/CuCl and aq. NH4Cl solution generated selectively two stereogenic centers at C(α) and C(β) providing, after flash chromatography and crystallization, acylsultams 5 in high purity. Mild cleavage afforded the recovered sultam auxiliary 1 and enantiomerically pure carboxylic acids 7.