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Updated: Jun 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
Efficient synthesis of E-alpha-haloenones through chemoselective alkyne activation over allene with triazole-Au
Dawei Wang1, Xiaohan Ye, Xiaodong Shi
1C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, USA.
Abstract:
The E-alpha-haloenones were prepared through a triazole-Au complex (TriA-Au) catalyzed propargyl acetate rearrangement and sequential allene halogenation. The reactions proceeded with only 1% catalyst loading, giving the challenging kinetic products in excellent yields and good to excellent stereoselectivity. These results not only provided the first example for the synthesis of challenging kinetic E-haloenones, but also revealed triazole-Au complexes as effective catalysts in promoting chemoselective activation of alkynes over allenes.
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