Dehydrogenative cross-coupling reaction by cooperative transition-metal and Brønsted acid catalysis for the synthesis of β-quinolinyl α-amino acid esters.

A novel dehydrogenative cross-coupling (DCC) reaction between methylquinoline derivatives and N-aryl glycine esters was developed by a cooperative catalysis of copper salt and Brønsted acid, affording an efficient synthesis of β-quinolinyl α-amino acid esters. A plausible mechanism using a proton to activate the methylquinoline derivative and copper(II) to activate N-aryl glycine ester has been proposed.