A Regioselective Metal-Free Construction of 3-Aroyl Coumarins by Csp2-H Functionalization.

A successive metal-free TBHP-mediated regioselective C-H functionalization of coumarins toward expedient synthesis of 3-aroyl coumarins is unveiled. The ongoing method conducted through the reaction of either coumarins or coumarin-3-carboxylic acids with aromatic aldehydes. The optimized reaction condition also worked well with benzyl alcohols and styrenes as surrogates for aldehydes, which bear latent carbonyl functionality.