An Efficient and Rapid Synthesis of 1,4-Dihydropyrano[2,3-c]Pyran and 1,4-Dihydropyrano[2,3-c]Quinoline Derivatives Using Copper Nanoparticles Grafted on Carbon Microspheres

A rapid and efficient one-pot three-component synthesis of 2-amino-3-cyano-4-aryl-7-methyl-5-oxo-4,5-dihydro-pyrano-[3,2-c]pyran and 2-amino-3-cyano-4-aryl-6-methyl5,6-dihydro-5-oxo-4H-pyrano-[3,2-c]quinoline derivatives catalyzed by copper nanoparticles grafted on carbon microspheres is developed. The use of heterogeneous catalyst, mild reaction conditions, and excellent yield of the corresponding products are the key features of the present protocol.