Copper‐Photocatalyzed Borylation of Organic Halides under Batch and Continuous‐Flow Conditions

Abstract

Abstract The copper‐photocatalyzed borylation of aryl, heteroaryl, vinyl and alkyl halides (I and Br) was reported. The reaction proceeded using a new heteroleptic Cu complex under irradiation with blue LEDs, giving the corresponding boronic‐acid esters in good to excellent yields. The reaction was extended to continuous‐flow conditions to allow an easy scale‐up. The mechanism of the reaction was studied and a mechanism based on a reductive quenching (Cu I /Cu I */Cu 0 ) was suggested.