A New Stereoselective Synthesis of Cyclopropanes Containing Quaternary Stereocentres <i>via</i> Organocatalytic Michael Addition to Vinyl Selenones

Abstract

Abstract A novel organocatalytic method for the stereoselective synthesis of highly substituted cyclopropanes is reported. The Michael adducts, generated through the addition of α‐substituted cyanoacetates to easily accessible vinyl selenones catalyzed by a bifunctional ureidic catalyst, smoothly cyclize by intramolecular alkylation induced by a de‐ethoxycarbonylation process. The one‐pot sequence generates cyclopropanes bearing adjacent tertiary and quaternary stereocentres as single Z ‐isomers in moderate to high yields and good enantiomeric excesses.