Palladium-Catalyzed Secondary C(sp3)-H Arylation of 2-Alkylpyridines

A pyridyl group-assisted palladium-catalyzed secondary C(sp(3))-H arylation protocol was developed. A substituent at the 3-position of the pyridyl group is proved to be important for promoting C-H arylation and controlling the regioselectivity. Aryl iodides can be used as coupling partners. The reaction proceeded in good to excellent yields with good functional group tolerance, even on the gram-scale. The preliminary asymmetric reaction was investigated using an L-proline derivative as a chiral ligand.