a rapid and highly effectual protocol for the synthesis of bis-coumarins using triethylaminium-n-sulfonic acid tetrachloroaluminate under solvent-free conditions

In this work, a rapid and highly effectual protocol for the synthesis of bis-coumarins has been developed. the one-pot quasi three-component reaction of aromatic aldehydes (1 eq.) with 4-hydroxycoumarin (2 eq.) in the presence of catalytic amount of protic acidic ionic liquid triethylaminium-n-sulfonic acid tetrachloroaluminate (tsat) under solvent-free conditions afforded the mentioned compounds in high yields and short reaction times.