NHC-Pd(II)-cinnamyl Complex-catalyzed Suzuki−Miyaura Cross-coupling of Arylboronic Acids with Aryl Chlorides under Mild Conditions

Abstract A well-defined N-heterocyclic carbenes-Pd(II)-cin complex 1 was found to be an effective catalyst for the Suzuki−Miyaura coupling of arylboronic acids with aryl chlorides at room temperature, giving the desired biaryls in good to excellent isolated yields. The reaction scope showcases its ease and breadth in terms of functional-group tolerance. Both electron-donating and electron-withdrawing sterically hindered aryl chlorides, as well as sterically hindered arylboronic acids, were effectively coupled. In air, the catalytic reaction was conducted in ethanol with K2CO3 at room temperature, enriching an environmentally friendly, convenient, and alternative method for the synthesis of biaryl compounds.