An Efficient, Simple and Green Zn(Phen)2Cl2 Complex Catalyzed Synthesis of 4‐H‐Benzo[b]pyrans in Water at Ambient Temperature

An efficient method for the synthesis of 4-H-benzo[b]pyrans has been developed by the use of Zn(Phen)2Cl2(2 mol%) as an ecofriendly catalyst. The mixture of an appropriate aldehyde, malononitrile and dimedone in the presence of the Zn(Phen)2Cl2 as an inorganic catalyst in water at room temperature resulted excellent yields of the corresponding products in 5 min. Very short experimental time of the reaction, excellent yields, use of water as a green solvent, simple work-up and uses no extra catalyst and purification are the advantages of this method.