Synthesis of Functionalized α-Pyrone and Butenolide Derivatives by Rhodium-Catalyzed Oxidative Coupling of Substituted Acrylic Acids with Alkynes and Alkenes

The straightforward and efficient synthesis of alpha-pyrone and butenolide derivatives has been achieved by the rhodium-catalyzed oxidative coupling reactions of substituted acrylic acids with alkynes and alkenes, respectively. Some alpha-pyrones obtained exhibit solid-state fluorescence.