The Mannich reaction in the synthesis of N,S-containing heterocycles 12. First example of aminomethylation involving 2-thioxonicotinamide derivative: synthesis of 3,5,7,11-tetraazatricyclo[7.3.1.02,7]tridec-2-ene-9-carboxamides

Abstract

Piperidinium 6-amino-5-cyano-3-N-(4-methylphenyl)carbamoyl-4-phenyl-1,4-dihydro-pyridine-2-thiolate upon the action of primary amines and excess formaldehyde undergoes aminomethylation to form 3,5,7,11-tetraazatricyclo[7.3.1.02,7]tridec-2-ene-9-carboxamides in 36–52% yields.