An Iridium/Aluminum Cooperative Strategy for the beta-C(sp(3))-H Borylation of Saturated Cyclic Amines

Despite the widespread success in the functionalization of C(sp(2))-H bonds, the deliberate functionalization of C(sp(3))-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 beta-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.

Automated summary

Herein, an iridium/aluminum cooperative catalytic system has been reported for the beta-selective C-H borylation of saturated cyclic amines and lactams. An enantioselective variant has also been achieved using chiral aluminum catalysts, resulting in high stereocontrol in the formation of C-B bonds. Computational studies suggest that the formation of a Lewis pair with the substrates is crucial for lowering the energy of the rate-determining reductive elimination step.