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Updated: Oct 26, 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
Synthesis of alkyl-tethered PAL probes enabled by tandem arene iodination/Ni-catalyzed reductive coupling
Fan Wu1, Yongming Zhang1, Honger Yao2
1Institute of Drug Discovery Technology and Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo, Zhejiang 315211, China. wufan@nbu.edu.cn.
Abstract:
A general strategy for the construction of photoaffinity labeling (PAL) probes through formal aromatic C-H alkylation is reported. This method combines I2/Selectfluor-mediated arene iodination with nickel-catalyzed reductive cross-coupling using a rationally designed bifunctional redox-active ester that serves simultaneously as an alkyl donor and a masked precursor to a PAL probe. This protocol enables the direct conversion of diverse (hetero)arenes, including drug-like molecules, into alkyl-linked, fully functionalized PAL probes without the need for preinstalled polar functional handles. In-gel fluorescence imaging further demonstrates that the resulting PAL probes undergo UV-dependent labeling of cellular proteins, while competition experiments reveal specific target engagement. These results highlight the minimal structural perturbation introduced by this design and underscore its utility in chemoproteomic applications.
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