Boryl Radical Mediated Hydro(gem-diboryl)alkylation of Alkenes with Sterically Hindered NHC Boranes.

NHC boryl radical mediated halogen atom transfer (XAT) is useful in organic synthesis. Yet, most of the reaction ends only with reducing the halogen to hydrogen, that is, the C-X to C-H. This is especially dominant for electron-deficient alkyl halides, where the formed electrophilic radical reacts rapidly with NHC boranes. Herein, by employing a sterically hindered NHC borane as the boryl radical precursor (IPr·BH3), we were able to use the electrophilic-deficient alkyl halide (α-Iodide gem-di(B(pin))methane) in the C-C bond formation reaction. Mono-, disubstituted styrene, aliphatic alkenes, and heteroatom-substituted alkenes were used as reaction partners. Forty hydro(gem-diboryl)methylation products were obtained at room temperature in moderate to good yields. Detailed mechanistic studies revealed that the reaction mainly involved the radical process.

• Publication year

  2024

• Venue

  Organic Letters

• Publication date

  2024-12-09

• Fields of study

  Medicine, Chemistry

• Identifiers
  DOI 10.1021/acs.orglett.4c04018PMID 39651998
• External record

  Open on Semantic Scholar

• Source metadata

  Semantic Scholar, PubMed

• No claims are published for this paper.

• No concepts are published for this paper.

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