Eco-friendly synthesis of diverse and valuable 2-pyridones by catalyst- and solvent-free thermal multicomponent domino reaction

An efficient and highly eco-friendly synthesis of diverse and functionalized 2-pyridone derivatives in good yield via the thermal multicomponent reaction of 4-oxo-4H-chromene-3-carbaldehydes with 1,3-diketoesters and anilines or primary aliphatic amines under catalyst-and solvent-free conditions is described. This reaction proceeds via domino Knoevenagel condensation/Michael addition/ring opening/ring closure reactions.