Aryl Radical Enabled, Copper-Catalyzed Sonogashira-Type Cross-Coupling of Alkynes with Alkyl Iodides
Xiaojun Zeng1, Chao Wang2, Wenhao Yan2
1School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, Jiangxi 330031, China.
Abstract:
Despite the success of Sonogashira coupling for the synthesis of arylalkynes and conjugated enynes, the engagement of unactivated alkyl halides in such reactions remains historically challenging. We report herein a strategy that merges Cu-catalyzed alkyne transfer with the aryl radical activation of carbon-halide bonds to enable a general approach for the coupling of alkyl iodides with terminal alkynes. This unprecedented Sonogashira-type cross-coupling reaction tolerates a broad range of functional groups and has been applied to the late-stage cross-coupling of densely functionalized pharmaceutical agents as well as the synthesis of positron emission tomography tracers.
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