Addition Reactions of Heterocyclic Compounds. Part 71. Formation of 1,3a,3b,4,6a,6b-Hexahydrocyclopentacyclobutapyrroles from Dimethyl Acetylenedicarboxylate and 1-Aryl-1,4-dihydropyridines

Article abstract of DOI:10.1039/P19800000081

1-Aryl-1,4-dihydropyridines combine with dimethyl acetylenedicarboxylate to form tetramethyl 1-aryl-1,3a,3b,4,6a,6b-hexahydrocyclopenta<3,4>cyclobuta<1,2-b>pyrrole-3,3a,6,6a-tetracarboxylates, the structures of which were deduced from their ¹H,