Multifunctional chromenes have been efficiently synthesized in aqueous medium at room temperature using deep eutectic mixture of choline chloride:urea. In this one-pot synthesis, the benzylidenemalononitrile firstly formed by Knoevenagel condensation of aldehyde and malononitrile eventually underwent Michael addition-cyclization with dimedone and offered the chromenes in good to excellent yield.
Keywords: 5-exo-Cyclisation, 6-endo Cyclization, AIBN, Pyrimidine, Radical reaction, Sulfur heterocycles, Tributyltin hydride.