Pd-Catalyzed Synthesis of 1,4-Dihydro-pyridines via a Multicomponent Reaction

Significance

A Pd-catalyzed three-component synthesis of 1,4-dihydropyridines is described. Starting from simple or easily available aromatic aldehydes, aryl amines and terminal olefins, the reaction proceeds smoothly under mild conditions and an O₂ atmosphere to afford 2,6-unsubstituted 1,4-dihydropyridines in moderate to good yields. The process constitutes an efficient modified Hantzsch reaction. However, the reaction yields were greatly decreased when the process was conducted in laboratory air or at a lower temperature.