Potassium sodium tartrate as a versatile and efficient catalyst for the one-pot synthesis of pyran annulated heterocyclic compounds in aqueous media

Potassium sodium tartrate (KNaC4H4O6 center dot 4H(2)O) was applied as an efficient catalyst for the one-pot, three-component condensation reactions consisting of aromatic aldehydes, malononitrile, and 4-hydroxycoumarin/dimedone/alpha-naphthol/thiobarbituric acid in aqueous ethanol. Use of nontoxic reaction components, short reaction times, environmental, easy work-up, and high yields are some important advantages of this method.