Copper oxide catalyzed domino process for the synthesis of substituted 2H-pyran-2-ones and polyhydroxy coumarin derivatives

An efficient method for the synthesis of substituted 2H-pyran-2-ones and polyhydroxy coumarin derivatives has been developed via CuO-catalyzed C-C bond formation followed by intramolecular cyclization reaction by reacting electron-deficient alkynes with 1,3-diketones and polyhydroxy benzenes, respectively. The domino reaction proceeded smoothly by using commercially available catalysts under reflux in toluene with very good yield.