Synthesis of α-Ketone-isoquinoline Derivatives via Tandem Ruthenium(II)-Catalyzed C-H Activation and Annulation.

A new ruthenium(II)-catalyzed tandem C-H activation/cyclization/hydrolysis cascade process of 2 H-imidazoles and alkynes for facile and regioselective access to α-ketone-isoquinolines has been successfully developed. 2 H-Imidazole as the novel traceless directing group has been well applied in this paper. The protocol features mild reaction conditions and easily accessible starting materials, and α-ketone-isoquinolines could be applied to further construct more complex heterocyclic compounds.