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

Abstract

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 Csp²–H from the N-alkyl-N-phenylacrylamide with the aldehyde Csp²–H bond (–CHO), followed by metal-mediated direct aryl Csp²–H functionalization/cyclization to afford 3-(2-oxo-2-arylethyl)indolin-2-ones in good yields under mild reaction conditions without organic solvents involved.