An straightforward entry to new pyrazolo-fused dibenzo[1,4]diazepines

Org Biomol Chem. 2011 Apr 7;9(7):2251-7. doi: 10.1039/c0ob00812e. Epub 2011 Feb 7.

Abstract

A series of novel pyrazolodibenzo[1,4]diazepines has been synthesized with good overall yields. The diarylpyrazole intermediates, with structure similarity to biologically relevant compounds such as currently marketed drugs like rimonabant or celecoxib, were prepared by a tandem sequence amine-exchange/heterocyclization starting from readily available enaminones and arylhydrazines. The key step of this efficient methodology was C(aryl)-N bond construction, accomplished by a palladium-catalyzed intramolecular N-arylation reaction, which was conducted in both homogeneous and polymer-supported versions. Reaction scope of such protocols and recycling of the heterogeneous catalyst were also examined.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Benzodiazepines / chemistry*
  • Catalysis
  • Molecular Structure
  • Nitrogen Compounds
  • Oxidation-Reduction
  • Pyrazoles / chemistry*

Substances

  • Nitrogen Compounds
  • Pyrazoles
  • Benzodiazepines