Rapid and Efficient Aromatization of Hantzsch 1,4-Dihydropyridines with Potassium Peroxomonosulfate Catalyzed by Manganese(III) Schiff Base Complexes

Rapid and efficient oxidation of Hantzsch 1,4-dihydropyridine with Potassium peroxomonosulfate is reported. The Mn(III)-salophen/monopersulfate catalytic system converts 1,4-dihydropyridines to their corresponding pyridine derivatives at room temperature in a 1:1, CH3CN/H2O mixture. The ability of various Schiff base complexes in the oxidation of 1,4-dihydropyridine was also investigated.