Metal-Free Coupling of 2-Vinylphenols and Carboxylic Acids: An Access to 3-Acyloxy-2,3-dihydrobenzofurans

A new coupling reaction between 2-vinylphenols and carboxylic acids was developed to synthesize 3-acyloxy-2,3-dihydrobenzofurans using Bu4NI as a catalyst and t-BuOOH as an oxidant. This simple and practical methodology is notable due to the ability to complete it under metal-free conditions, with easily available precursors, resulting in a product with high atom economy and high functional group tolerance. Upon the basis of experimental observations and literature, a plausible mechanism is proposed.