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

Abstract

Abstract Successive treatment of conjugated N ‐enoylsultams 2 with alkyl Grignard reagents/CuCl and aq. NH 4 Cl 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 .