An efficient Mannich-type one-pot synthesis of 3,5,7,11-tetraazatricyclo [7.3.1.02,7]tridec-2-ene derivatives starting from functionalized 1,4-dihydropyridines

3,5,7,11-Tetraazatricyclo[7.3.1.0(2,7)]tridec-2-ene derivatives were prepared in one-pot manner from N-methylmorpholinium 6-amino-3,5-dicyano-4-spiro(1'-cycloalkane)-1,4-dihydropyridine-2-thiolates, primary amines, and formaldehyde in 70-88% yields. The structure of 5,11-dibenzyl-13-spiro(1'-cyclopentane)-8-thioxo-3,5,7,11-tetraazatricyclo[7.3.1.0(2,7)]tridec-2-ene-1,9-dicarbonitrile was determined by X-ray diffraction analysis.