α-Amino Acid Sulfonamides as Versatile Sulfonylation Reagents: Silver-Catalyzed Synthesis of Coumarins and Oxindoles by Radical Cyclization

Kyalo Stephen Kanyiva, Daisuke Hamada, Sohei Makino, Hideaki Takano, Takanori Shibata

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3 Citations (Scopus)

Abstract

We developed a silver-catalyzed strategy for the generation of sulfonyl radicals from sulfonamides derived from α-amino acids. The reaction proceeded via a decarboxylation, N–S bond cleavage and radical cyclization sequence and allows the difunctionalization of alkynes and the synthesis of 3-sulfonylated coumarins. The reaction tolerated a broad scope of substrates and functional groups and could be extended to the synthesis of oxindoles and an isoquinolinedione by the capturing of the sulfonyl radical with an alkene moiety. Moreover, the proposed mechanism was supported experimentally and by DFT calculations.

Original languageEnglish
Pages (from-to)5905-5909
Number of pages5
JournalEuropean Journal of Organic Chemistry
Volume2018
Issue number43
DOIs
Publication statusPublished - 2018 Nov 25

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Keywords

  • Amino acids
  • Coumarins
  • Oxindoles
  • Silver
  • Sulfonamides

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Organic Chemistry

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