An improved synthesis of 2,2−-((4-substituted phenyl) methylene) difurans by Ultrasound irradiation

A new series of 2,2−((4-substituted phenyl) methylene) difuran was synthesized by one-pot cyclocondensation of aldehyde with excess furan at room temperature using trifluoro acetic acid as a catalyst under ultrasound irradiation in the absence of solvent. The products were compared with the classical condensation reactions. This method consistently enjoys the advantages of mild reaction conditions, excellent yields, easy work up and short time