Regiocontrol by Halogen Substituent on Arynes: Generation of 3-Haloarynes and Their Synthetic Reactions

Abstract The use of arynes as highly reactive intermediates has attracted substantial attention in organic synthesis. To enhance the utility of arynes, the regiocontrol in the reactions of unsymmetrically substituted arynes is an important task. The introduction of halogen substituent at 3-position of arynes leads to sufficient regiocontrol for various synthetic reactions. This short review highlights the utility of 3-halo­arynes in organic synthesis and discusses the distortion models used to explain regioselectivity, representative reactions of 3-haloarynes generated from polyhaloarenes, and the preparation and reactions of easily activatable aryne precursors. 1 Introduction 2 Distortion Models 3 Reaction of Precursors Activated by an Organometallic Reagent or Base 4 Preparation of Easily Activatable Precursors 5 Reactions of Easily Activatable Precursors 6 Concluding Remarks