Regioselective C–H alkynylation with haloalkynes enabled by nitrogen functionalities via Rh catalysis†

Regioselective introduction of the versatile alkyne functionality would enable rapid construction of molecular complexity; however, sterically hindered silyl-containing alkynylation reagents are typically required, thus, hampering further applications. Herein, we have developed a transformable nitrogen functionality-enabled regioselective C–H alkynylation cascade with aliphatic haloalkynes, furnishing alkynes and heterocycles, which thus facilitated concise synthesis of CB2 receptor agonist and protein kinase inhibitor analogues.