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Updated: Dec 25, 2025

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

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

Hypervalent Iodine(III)-Catalysed Enantioselective α-Acetoxylation of Ketones

Tobias Hokamp¹, Thomas Wirth¹

¹School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, UK.

Chemistry (Weinheim an Der Bergstrasse, Germany)

|April 2, 2020

Abstract:

An enantioselective catalytic synthesis of α-acetoxylated ketones through I(I)/I(III) catalysis using a resorcinol/lactamide-based chiral iodoarene is reported. Catalyst turnover by in situ generation of the active iodine(III) derivative is achieved by oxidation with mCPBA in the presence of acetic acid. The prior transformation of ketones to easily accessible acetyl enol ethers is beneficial and yields up to 97 % with enantioselectivities up to 88 % ee are obtained using only low catalyst loadings of only 5 mol % under mild reaction conditions.

Keywords:

catalysis hypervalent iodine ketones stereochemistry α-acetoxylation

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