Synthesis of Dihydropyrano[3,2- c]pyrazoles via Double Bond Migration and Ring-Closing Metathesis

Molecules. 2019 Jan 15;24(2):296. doi: 10.3390/molecules24020296.

Abstract

Three types of pyrazole-fused heterobicycles, i.e., 1,5-, 1,7-, and 2,5-dihydropyrano[3,2-c]pyrazoles, were synthesized from 4-allyloxy-1H-pyrazoles. A sequence of the Claisen rearrangement of 4-allyloxy-1H-pyrazoles, ruthenium-hydride-catalyzed double bond migration, O-allylation, and ring-closing metathesis was employed in this study.

Keywords: dihydropyrano[3,2-c]pyrazole; double bond migration; ring-closing metathesis; ruthenium hydride catalyst; synthesis.

MeSH terms

  • Catalysis
  • Chemistry Techniques, Synthetic*
  • Molecular Structure
  • Pyrazoles / chemical synthesis*
  • Pyrazoles / chemistry
  • Ruthenium / chemistry

Substances

  • Pyrazoles
  • Ruthenium