Arylboration of Internal Alkynes by Cooperative Palladium/Copper Catalysis

Abstract A versatile method for the arylboration of internal alkynes with aryl chlorides or bromides and bis(pinacolato)diboron has been developed. This method tolerates various functional groups, including acetyl, methoxycarbonyl, cyano, and fluoro substituents, and affords a range of tri-substituted vinylboronates, which are highly useful intermediates for the synthesis of tetra-substituted ethenes, in high yield and regioselectivity.