Copper-catalyzed oxidative cascade coupling of N-alkyl-N-phenylacrylamides with aryl aldehydes

An oxidative cascade coupling reaction was developed between N-alkyl-N-phenylacrylamides and aryl aldehydes using CuCl2/TBHP (tert-butyl hydroperoxide) as a catalyst and oxidant. The reaction involves oxidative cross coupling of the activated alkene Csp(2)-H from the N-alkyl-N-phenylacrylamide with the aldehyde Csp(2)-H bond (-CHO), followed by metal-mediated direct aryl Csp(2)-H functionalization/cyclization to afford 3-(2-oxo-2-arylethyl)indolin-2-ones in good yields under mild reaction conditions without organic solvents involved.