Diastereo- and Enantioselective Iridium Catalyzed Carbonyl (α-Cyclopropyl)allylation via Transfer Hydrogenation

The first examples of diastereo‐ and enantioselective carbonyl α‐(cyclopropyl)allylation are reported. Under the conditions of iridium catalyzed transfer hydrogenation using the chiral precatalyst (R)‐Ir‐I modified by SEGPHOS, carbonyl α‐(cyclopropyl)allylation may be achieved with equal facility from alcohol or aldehyde oxidation levels. This methodology provides a conduit to hitherto inaccessible inaccessible enantiomerically enriched cyclopropane‐containing architectures. Alcohol solves problems: Chiral iridium catalysts modified by (R)‐SEGPHOS catalyze the transfer hydrogenative coupling of racemic α‐cyclopropyl allyl acetate with diverse primary alcohols with good anti‐diastereo‐ and exceptional enantioselectivity. These processes represent the first diastereo‐ and enantioselective carbonyl (α‐cyclopropyl)allylations.