A Versatile Enantioselective Catalytic Cyclopropanation‐Rearrangement Approach to the Divergent Construction of Chiral Spiroaminals and Fused Bicyclic Acetals

Abstract

AbstractA highly enantioselective synthesis of various chiral heterobicyclic molecules including spiroaminals and fused bicyclic acetals has been developed via a chiral copper catalyzed cyclopropanation‐rearrangement (CP‐RA) approach under mild reaction conditions. Remarkably, the asymmetric CP‐RA for exocyclic vinyl substrates without a pro‐stereogenic carbon at the β‐position has been realized for the first time and a broad substrate scope with excellent results (33 examples; 34–99 % yields; >95/5 dr and 91–99 % ee) has been achieved. An application of a successive enantioselective CP‐RA approach was also described, providing a concise access to complex chiral heteropolycycles.