Michael reaction in synthesis of 6-amino-4-(4-butoxyphenyl)-3,5-dicyanopyridine-2(1H)-thione

Article abstract of DOI:10.1007/BF02315182

The reaction of 4-butoxybenzalcyanoacetic ester with cyanothioacetamide yielded 6-amino-4-(4-butoxyphenyl)-3,5-dicyanopyridine-2(1H)-thione, also synthesized by recyclization of 2,6-diamino-4-(4-butoxyphenyl)-3,5-dicyano-4H-thiopyran and condensation of 4-butyoxybenzaldehyde with a two-fold excess of cyanothioacetamide. Substituted 2-alkylthiopyridines and thieno[2,3-b]pyridines were obtained with the indicated pyridinethione. 1998 Plenum Publishing Corporation.