Stereoselective Synthesis of Fused Vinylcyclopropanes by Intramolecular Tsuji-Trost Cascade Cyclization

Abstract

A stereoselective intramolecular Tsuji-Trost cascade cyclization of (homo)allylic vicinal diacetates with a pendant β-ketoamide or related carbon nucleophile to give γ-lactam-fused vinylcyclopropanes is reported. In addition to two new rings, the products contain three new C-C stereocenters (two of which are quaternary) with a 9:1 dr. Moreover, the reaction proceeds in >94% enantiospecificity with optically enriched starting materials, using an inexpensive carbohydrate as the source of chirality.