Synthesis of 4H-Pyran Derivatives Under Solvent-Free and Grinding Conditions

Abstract

Based on x-ray diffraction analysis, we have proved that the recently published results for ethyl 6-amino-5-cyano-4-aryl-1,4-dihydropyridine-3-carboxylate synthesis is in fact an environmentally friendly synthesis of 6-amino-5-cyano-4-aryl-4H-pyran derivatives using a multicomponent room-temperature grinding procedure of ethyl acetoacetate, [(2-aryl)methylene]malononitriles, and ammonium acetate.