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Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
K2S2O8-Promoted C3-Bromination of Heteroarenes with Sodium Bromide
Yucai Tang1, Jiale Liu1, Jiaming Huang1
1College of Chemistry and Materials Engineering, Engineering Research Center of Hunan Province for Recycling Technology of Electroplating Wastewater, Hunan University of Arts and Science, Changde415000, China.
Abstract:
A K2S2O8-promoted C3-bromination of heteroarenes using sodium bromide was developed. This method provides efficient access to a broad array of C3-brominated heteroarenes, including quinoxalin-2(1H)-ones, cinnolin-4(1H)-ones, coumarins, and oxazinone derivatives, in moderate to good yields (38 examples). Notably, this approach is applicable to both the late-stage functionalization of complex pharmaceutical agents and gram-scale synthesis. Mechanistic studies indicate that trifluoroacetic acid plays a crucial role in the reaction.
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