Palladium-assisted multicomponent cyclization of aromatic aldehydes, arylamines and terminal olefins under molecular oxygen: an assembly of 1,4-dihydropyridines

The palladium-assisted one-pot three-component reactions of aldehydes, amines and olefins proceeded smoothly to give 2,6-unsubstituted 1,4-dihydropyridines (1,4-DHPs) using molecular oxygen as a sole oxidant. It also provides efficient Pd-catalyzed aerobic oxidation access to the anti-Markovnikov oxidative amination products of olefins from primary aromatic amines and alkenes. The method is atom-efficient, using cheap and easily available starting materials and an environmentally benign oxidant.