Efficient synthesis of a new class of sulfonamide-substituted coumarins

A convenient synthesis of new sulfonamide-substituted coumarins is reported. N-Sulfonyl aldimines are synthesized from the reaction of arylaldehydes and p-toluenesulfonamide. Next, the prepared N-sulfonyl aldimines are reacted with 5,7-dihydroxy-4-methylcoumarin using 40 mol % of NaOH to produce sulfonamide-substituted coumarin derivatives in good to excellent yields. (C) 2015 Elsevier Ltd. All rights reserved.