Ligand-enabled ortho-C-H olefination of phenylacetic amides with unactivated alkenes

Chem Sci. 2017 Dec 8;9(5):1311-1316. doi: 10.1039/c7sc04827k. eCollection 2018 Feb 7.

Abstract

Although chelation-assisted C-H olefination has been intensely investigated, Pd(ii)-catalyzed C-H olefination reactions are largely restricted to acrylates and styrenes. Here we report a quinoline-derived ligand that enables the Pd(ii)-catalyzed olefination of the C(sp2)-H bond with simple aliphatic alkenes using a weakly coordinating monodentate amide auxiliary. Oxygen is used as the terminal oxidant with catalytic copper as the co-oxidant. A variety of functional groups in the aliphatic alkenes are tolerated. Upon hydrogenation, the ortho-alkylated product can be accessed. The utility of this reaction is also demonstrated by the late-stage diversification of drug molecules.