Cobalt-Catalyzed Cross-Dehydrogenative Coupling Reaction between Unactivated C(sp)-H and C(sp)-H Bonds.

Catalytic oxidative cross-dehydrogenative coupling between unactivated C(sp)-H and C(sp)-H bonds is achieved by the cobalt-catalyzed o-alkylation reaction of aromatic carboxamides containing (pyridin-2-yl)isopropyl amine (PIP-NH) as a N,N-bidentate directing group. Many different C(sp)-H bonds in alkanes, toluene derivatives and even in the α-position of ethers and thioethers can be used as coupling partners. This method has a broad substrate scope and the tolerance of various functional groups.