Iron-Promoted Oxidative Alkylation/Cyclization of Ynones with 4-Alkyl-1,4-dihydropyridines: Access to 2-Alkylated Indenones

J Org Chem. 2022 Jul 1;87(13):8599-8610. doi: 10.1021/acs.joc.2c00766. Epub 2022 Jun 15.

Abstract

An iron-promoted oxidative tandem alkylation/cyclization of ynones with 4-alkyl-substituted 1,4-dihydropyridines for the efficient synthesis of 2-alkylated indenones is described. The process occurs via oxidative homolysis of a C-C σ-bond in 1,4-dihydropyridines to generate an alkyl radical followed by the addition of C-C triple bonds in ynones and intramolecular cyclization. A wide range of alkyl radicals could be efficiently transferred to generate a series of synthetically useful 2-alkylated indenones with excellent selectivity under mild conditions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkylation
  • Cyclization
  • Dihydropyridines* / chemistry
  • Iron / chemistry
  • Oxidative Stress

Substances

  • Dihydropyridines
  • Iron