Photochemical Sandmeyer-type Halogenation of Arenediazonium Salts

Chemistry. 2022 Feb 16;28(9):e202103669. doi: 10.1002/chem.202103669. Epub 2022 Jan 15.

Abstract

Trihalide salts were found to efficiently promote photochemical dediazotizing halogenations of diazonium salts. In contrast to classical Sandmeyer reactions, no metal catalysts are required to achieve high yields and outstanding selectivities for halogenation over competing hydridodediazotization. Convenient protocols are disclosed for synthetically meaningful brominations, iodinations, and chlorinations of diversely functionalized derivatives.