Preparation of 3-Acyl-4-arylcoumarins via Metal-Free Tandem Oxidative Acylation/Cyclization between Alkynoates with Aldehydes

A new and efficient metal-free tandem acylation/cyclization of alkynoates with aldehydes was developed for the synthesis of 3-acyl-4-arylcoumarins. The reaction was achieved by the addition of acyl radical to alkynes and a C-H bond functionalization to form two new C-C bonds simultaneously.