Condensation of ethyl 2-cyano-3-ethoxypropenoate and 2-cyano-3-ethoxy-N-phenylpropenamide with cyanothioacetamide and N-methylmorpholine gave N-methylmorpholinium 1-amino-2,4-dicyano-4-phenylcarbamoyl(ethoxycarbonyl)-1,3-butadiene-1-thiolates which were converted into pyridine-2-thiol derivatives: N-methylmorpholinium pyridine-2-thiolate, 2-alkylthiopyridines, and thieno[2,3-b]pyridine.
Condensation of ethyl 2-cyano-3-ethoxypropenoate and 2-cyano-3-ethoxy-N-phenylpropenamide with cyanothioacetamide and N-methylmorpholine gave N-methylmorpholinium 1-amino-2,4-dicyano-4-phenylcarbamoyl(ethoxycarbonyl)-1,3-butadiene-1-thiolates which were converted into pyridine-2-thiol derivatives: N-methylmorpholinium pyridine-2-thiolate, 2-alkylthiopyridines, and thieno[2,3-b]pyridine.