A catalyst and solvent free synthesis of polysubstituted 2-methylene-1,2-dihydropyridines

Synthesis of polysubstituted 2-methylene-1,2-dihydropyridines were accomplished by one-pot multicomponent reaction of 3-formylchromones, anilines and aliphatic 1,3-diones under catalyst and solvent-free reaction conditions. The reaction proceeds <i>via</i> Schiff base mediated, Michael addition followed by ring opening/ring closure sequential process resulting two new C–N and one C–C bonds formation. Neat reaction conditions and higher yields are the advantages of the protocol.