[3+2] Cycloaddition Reactions of Cyclopropyl Imines with Enones

A nickel-catalyzed [3+2] cycloaddition of cyclopropyl aldimines and enones has been developed. The process provides direct access to trisubstituted cyclopentanes, and the scope exceeds that of the corresponding reactions involving cyclopropyl ketones. A basis for the improved performance of cyclopropyl aldimines compared with cyclopropyl ketones is provided.