Abstract Conditions have been established for the sodium dithionite (Na 2 S 2 O 4) reduction of pyridinium salts 1 lacking electron-withdrawing substituents to their corresponding 1, 4- dihydropyridines (1, 4-DHPs) 2, a reaction which was previously reported to fail. The importance of hydrophobic effects for this reduction to take place could be recognized from the results obtained. The present procedure offers a very convenient route to a number of ...