Atom-Economical Synthesis of N-Arylamides Utilizing Isopropenyl Esters with Heterogeneous Acid Catalysts

Existing methods for the catalytic synthesis of N-arylamides are limited by a narrow substrate scope, high catalyst costs, and complicated purification processes of products. To overcome these limitations, this study developed an ecofriendly method for the synthesis of N-arylamides using isopropenyl esters. Isopropenyl esters activated using heterogeneous acid catalysts reacted smoothly even with less reactive arylamines to afford N-arylamides in high yields. This method exhibits a wide substrate scope and is applicable for the synthesis of various N-arylamides (33 examples, 46-99% yield). The developed method enabled the obtainment of high-purity products with a facile workup procedure and showed excellent process mass intensity values due to the reduction of chemical waste.