Coupling of alkynes and aryl halides with nickel-catalyzed Sonogashira reactions

Methods for incorporating alkynes into molecular skeletons have been the subject of continued research. Compared to the cross-couplings used to form C–C(sp3) and C–C(sp2) bonds, couplings that form C–C(sp) bonds, particularly those catalyzed by nickel, remain less explored. In this study, we present a single nickel-catalyzed cross-coupling of terminal alkynes with aryl iodides or bromides for constructing C(sp2)–C(sp) bonds. Our method provides high functional group tolerance and broad substrate scope, resulting in good yields. This nickel-catalyzed coupling reaction is a straightforward way to prepare optoelectronic materials and key building blocks for chemical biology. Notably, our method displays decent selectivity when multi-halide-substituted arenes are used as substrates. Finally, a plausible mechanism is postulated based on experimental studies and density functional theory calculations.