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Updated: Aug 6, 2025

Chemoselective Preparation of 1-Iodoalkynes, 1,2-Diiodoalkenes, and 1,1,2-Triiodoalkenes Based on the Oxidative Iodination of Terminal Alkynes

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Published on: September 12, 2018

Selective multi-electron aggregation at a hypervalent iodine center by sequential disproportionation.

Phong Thai¹, Brandon L Frey¹, Matthew T Figgins¹

¹Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA. powers@chem.tamu.edu.

Chemical Communications (Cambridge, England)

|March 20, 2023

Summary

This summary is machine-generated.

Sequential disproportionation reactions enable selective aggregation of electron-holes at hypervalent iodine centers. This chemistry achieves multielectron oxidation at a one-electron potential, advancing synthetic methodologies.

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Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes

Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes

Published on: September 8, 2013

Area of Science:

Organic Chemistry
Electrochemistry
Hypervalent Iodine Chemistry

Background:

Hypervalent iodine compounds are versatile reagents in organic synthesis.
Controlling the oxidation state and reactivity of hypervalent iodine is crucial for developing new synthetic transformations.

Purpose of the Study:

To demonstrate sequential disproportionation reactions for selective electron-hole aggregation at hypervalent iodine centers.
To achieve multielectron oxidation using a one-electron potential through controlled disproportionation.

Main Methods:

Anodic generation of iodanyl radicals.
Sequential disproportionation reactions involving iodanyl and iodosylbenzene intermediates.
Characterization of reaction products, including iodoxybenzene derivatives.

Main Results:

Selective aggregation of two- or four electron-holes at a hypervalent iodine center was achieved.
Anodic generation of iodanyl radicals led to iodosylbenzene derivatives.
Subsequent disproportionation yielded iodoxybenzene, demonstrating controlled oxidation.

Conclusions:

Sequential disproportionation offers a novel pathway for selective electron-hole aggregation in hypervalent iodine chemistry.
This methodology enables efficient multielectron oxidation at a low potential, expanding synthetic capabilities.