New methylene homologation method for cyclic ketones

Chemistry. 2012 Sep 17;18(38):11889-93. doi: 10.1002/chem.201201346. Epub 2012 Aug 14.

Abstract

Teaching new tricks to an old dog: By intercepting adducts between ketones and lithium trimethylsilyldiazomethane, a new Tiffeneau-Demjanov type methylene homologation could be realized in a single-step operation. Among proton sources and Lewis acids, silica gel was found to be the most effective reagent for the protonation of intermediates and their subsequent ring expansion (see scheme).

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Catalysis
  • Diazomethane / analogs & derivatives*
  • Diazomethane / chemistry
  • Ketones / chemistry*
  • Lewis Acids / chemistry*
  • Lithium / chemistry*
  • Methane / analogs & derivatives*
  • Methane / chemistry*
  • Molecular Structure
  • Protons
  • Trimethylsilyl Compounds / chemistry*

Substances

  • Ketones
  • Lewis Acids
  • Protons
  • Trimethylsilyl Compounds
  • Diazomethane
  • Lithium
  • Methane
  • trimethylsilyldiazomethane