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Updated: Oct 28, 2026

Chemoselective Preparation of 1-Iodoalkynes, 1,2-Diiodoalkenes, and 1,1,2-Triiodoalkenes Based on the Oxidative Iodination of Terminal Alkynes
Published on: September 12, 2018
Visible-light-mediated four-component stereoselective iodosulfonylation of alkynes with aryl thianthrenium salts
Zhou Zhang1,2, Zi-Jun Hu2, Ji-Quan Zhang1
1State Key Laboratory of Discovery and Utilization of Functional Components in Traditional Chinese Medicine, Guizhou Provincial Key Laboratory of Innovation and Manufacturing for Pharmaceuticals, School of Pharmaceutical Sciences, Guizhou Medical University, Guiyang 561113, P. R. China. zjqgmc@163.com.
Abstract:
A photoredox-catalysed four-component regio- and stereoselective iodosulfonylation of terminal alkynes with aryl thianthrenium salts, DABSO, and KI has been developed. This method enables the efficient, facile, and modular synthesis of difunctional (E)-β-iodovinyl sulfones, a class of privileged building blocks widely used in organic synthesis and medicinal chemistry, under mild reaction conditions. Avoiding harsh oxidants and high temperatures, the reaction proceeds through a visible-light photoredox radical tandem pathway and features exclusive regio- and stereoselectivity, a broad substrate scope, and excellent functional-group compatibility.
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