An Iridium/Aluminum Cooperative Strategy for the β-C(sp3)-H Borylation of Saturated Cyclic Amines

Despite the widespread success in the functionalization of C(sp²)−H bonds, the deliberate functionalization of C(sp³)−H bonds in a highly site- and stereoselective manner remains a longstanding challenge. Herein, we report an iridium/aluminum cooperative catalytic system that enables the β-selective C−H borylation of saturated cyclic amines and lactams. Furthermore, we have accomplished an enantioselective variant using binaphthol-derived chiral aluminum catalysts to forge C−B bonds with high levels of stereocontrol. Computational studies suggest that the formation of a Lewis pair with the substrates is crucial to lower the energy of the transition state for the rate-determining reductive elimination step.