Nickel-Catalyzed Stereospecific C-H Coupling of Benzamides with Epoxides.

A Ni(OAc)2 -catalyzed C-H coupling of 8-aminoquinoline-derived benzamides with epoxides has been developed. The reaction proceeds with concomitant removal of the 8-aminoquinoline auxiliary to form the corresponding 3,4-dihydroisocoumarins directly. Additionally, the nickel catalysis is stereospecific, and the cis- and trans-epoxides are converted into the corresponding cis- and trans-dihydroisocoumarins with retention of configuration, which is complementary to previously reported palladium catalysis. Moreover, while still preliminary, the Csp3 -H functionalization is also achieved in the presence of modified NiCl2 catalysts.