Metal-free meta-halogenation of cyclic diaryliodonium salts via aryne intermediates†
Abstract
Transition metal-catalyzed ortho-functionalization of cyclic diaryliodonium salts has been well developed. Herein we present a transition-metal free meta-halogenation of readily available cyclic diaryliodonium salts for the preparation of valuable 2,3′-dihalobiaryls which can be transformed into a wide range of functionalized biaryls. The key step of this green process is the base-mediated generation of a benzyne intermediate which was successfully captured and supported the proposed mechanism.