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Updated: Jul 12, 2026
Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes
Published on: September 8, 2013
Halogen-Bonding Complexes of Iodonium Ylides for Halogen Atom Transfer: C-H Alkylation of Heterocycles
Mengwei Zhang1, Chao Pi1, Chen Xing1
1Henan Key Laboratory of Chemical Biology and Organic Chemistry, Key Laboratory of Applied Chemistry of Henan Universities, State Key Laboratory of Coking Coal Resources Green Exploitation, Pingyuan Laboratory and College of Chemistry, Zhengzhou University, Zhengzhou 450052, P. R. China.
Abstract:
Halogen atom transfer (XAT) represents a mild and selective strategy for generating alkyl radicals from alkyl halides, yet it typically relies on photocatalysts or metal complexes as reductants. Accordingly, the development of greener and more efficient strategies for an XAT platform is highly desirable. Herein, a photoactive halogen-bonding (HB) complex has been developed, formed in situ from iodonium ylides and an organic base, to selectively generate aryl radicals as an XAT agent under visible-light or sunlight irradiation. Direct C-H alkylation of heterocycles with a broad range of alkyl iodides was achieved under metal- and photocatalyst-free conditions. Meanwhile, the generated aryl radicals also mediate hydrogen atom transfer (HAT) from simple alkanes as substrates, demonstrating the versatility of this protocol for the generation of diverse alkyl radicals. Remarkably, its practicality and potential application are highlighted by gram-scale synthesis, late-stage modification of drugs, and synthesis of bioactive compounds.
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