Construction of Multi‐Substituted Strained Carbocycles Enabledby Enantioselective Reduction with Sodium Borohydride

Comprehensive Summary The stereoselective reduction of strained molecules and subsequent synthetic transformations provide an efficient strategy to access multi‐substituted carbocycles. These carbocycles are important structural skeletons in natural products and bioactive molecules. We report here a Luche‐type enantioselective reduction of cyclobutenones and strained‐ring fused cyclic imides. This process utilizes the catalysis of Sc– N , N’ ‐dioxide ligand complex and NaBH 4 as reductant. Moreover, the developed methodology is applicable to the strained olefins, which are not tolerated under metal hydride conditions.