A sequential Pd/norbornene-catalyzed process generates o-biaryl carbaldehydes or ketones via a redox reaction or 6H-dibenzopyrans by C-O ring closure

Org Lett. 2012 Nov 16;14(22):5792-5. doi: 10.1021/ol302889t. Epub 2012 Nov 7.

Abstract

o-Biaryl carbaldeydes and ketones are obtained through the one-pot reaction of o-aryl iodides with o-bromobenzyl alcohols under the catalytic action of Pd and norbornene, in the presence of a base. The same reaction can also give dibenzopyrans by Pd and norbornene catalysis with a different termination, leading to C-O ring closure. In both cases the process first leads to a five-membered palladacycle, which controls C-C coupling, then to a seven-membered oxapalladacycle, which gives aldehydes and ketones or dibenzopyrans.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alcohols / chemistry
  • Aldehydes / chemical synthesis*
  • Aldehydes / chemistry
  • Benzopyrans / chemical synthesis*
  • Benzopyrans / chemistry
  • Catalysis
  • Hydrocarbons, Brominated / chemistry
  • Hydrocarbons, Iodinated / chemistry
  • Ketones / chemical synthesis*
  • Ketones / chemistry
  • Molecular Structure
  • Oxidation-Reduction
  • Palladium / chemistry*

Substances

  • Alcohols
  • Aldehydes
  • Benzopyrans
  • Hydrocarbons, Brominated
  • Hydrocarbons, Iodinated
  • Ketones
  • Palladium