A Rapid and Highly Effectual Protocol for the Synthesis of Biscoumarins using TriethylaminiumNsulfonic Acid Tetrachloroaluminate under SolventFree Conditions

In this work, a rapid and highly effectual protocol for the synthesis of       biscoumarins has been developed. The onepot quasi threecomponent reaction of aromatic aldehydes (1 eq.) with 4hydroxycoumarin (2 eq.) in the presence of catalytic amount of protic acidic ionic liquid triethylaminiumNsulfonic acid tetrachloroaluminate (TSAT) under solventfree conditions afforded the mentioned compounds in high yields and short reaction times.