KOAc-promoted alkynylation of α-C-H bonds of ethers with alkynyl bromides under transition-metal-free conditions

A novel KOAc-promoted alpha-position C-H activation and alkynylation of ethers with alkynyl bromides to 2-alkynyl ethers has been developed under transition-metal-free and simple reaction conditions. In addition, this methodology can also be extended to the vinylation of ethers with vinyl bromides in excellent regio- and stereo-selectivity. A wide range of direct C(sp)-C(sp(3)) and C(sp(2))-C(sp(3)) bonds has been formed through this protocol, which offers a new and alternative route.