Mild Synthesis of Chalcones via Rhodium(III)-Catalyzed C–C Coupling of Arenes and Cyclopropenones

A Rh­(III)-catalyzed aryl C–H bond insertion into cyclopropenones via a C–H activation pathway has been reported. A series of arenes bearing directing groups such as 2-pyridyl, 2-pyrimidyl, N-pyrazyl, and oxime can be applicable, providing chalcones in excellent yields under mild conditions. Several possible Rh­(III) intermediates in this reaction were investigated.