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Updated: May 13, 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
Electrophilic monoiodination of terminal alkenes
Sergiy V Yemets1, Tatyana E Shubina, Pavel A Krasutsky
1University of Minnesota, Natural Resources Research Institute, 5013 Miller Trunk Highway, Duluth, MN 55811, USA.
Abstract:
An excess of elemental iodine in N,N-dimethylacetamide enables effective 3/iodanylium-de-hydronation of terminal alkenes with 3-iodopropene derivatives and hydrogen iodide formation within minutes at room temperature. The optimal molar ratio of iodine to substrate was decreased to 1 : 1 when hydrogen iodide formed was oxidized on a platinum anode. The electrolytic oxidation recovers iodine as a reagent and diminishes the hydrogen iodide inhibitory action to accomplish the monoiodination. The proposed reaction mechanism is based on kinetic measurements and quantum mechanics calculations.
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