Rhodium-Catalyzed Oxidative Coupling of Benzoic Acids with Terminal Alkynes: An Efficient Access to 3-Ylidenephthalides

Herein we disclose the first example of transition-metal-catalyzed oxidative coupling/annulation of simple benzoic acids with terminal alkynes via C–H activation. A range of aromatic carboxylic acids and terminal alkynes have been found to be viable substrates in this reaction, providing a simple and efficient method for the synthesis of diverse 3-ylidenephthalides with complete Z selectivity.