Revisiting 1-chloro-1,2-benziodoxol-3-one: efficient ortho-chlorination of aryls under aqueous conditions

The application of 1-chloro-1,2-benziodoxol-3-one as a powerful chlorinating agent as well as oxidant for aniline derivatives is explored. The amide directing group assisted radical mediated ortho-selective chlorination proceeds in the absence of a radical initiator. Various electronically differentiated anilides and sulfonamides are tolerated under aqueous conditions.