Synthesis and properties of 3-cyano-4-(4-cyanophenyl)-1,4-dihydropyridine-2(3H)-thiones

Article abstract of DOI:10.1007/BF02297678

Piperidinium 3-cyano-4-(4-cyanophenyl)-1,4-dihydropyridine-2(3H)-thiolates were obtained by the condensation of 1,3-dicarbonyl compounds, 4-cyanobenzaldehyde, and cyanothiacetamide in the presence of an equimolar amount of piperidine. The acidification of these thiolates gave the corresponding1,4-dihydropyridine-2(3H)-thiones and pyridine-2(1H9-thione. Alkylation of 1,4-dihydropyridine-2-thiolates or the reaction mixture of the three-carbon condensation using iodacetamide gave 2-carbamoylmethylthio-1,4,5,6-tetrahydro- or 1,4-dihydropyridines, which were characterized by their conversion to 4,7-dihydrothieno[2,3-b]pyridines.