Caffeine: An efficient and reusable catalyst for the multicomponent synthesis of 2-amino-3-cyano-6-methyl-4-aryl-4H-pyrans

An efficient procedure for the synthesis of various 2-amino-3-cyano-6-methyl-4-aryl-4H-pyrans is reported. It has been found that Caffeine catalyse the condensation reaction of aromatic aldehydes, malononitrile and ethyl acetoacetate efficiently under EtOH-H₂O (1:1) at reflux conditions. This approach provides many merits such as high yields of products, clean, simple work-up, waste free, mild reaction conditions and commercially available catalyst.