Gas phase thermal reactions of exo-8-cyclopropyl-bicyclo[4.2.0]oct-2-ene (1-exo)

Molecules. 2014 Jan 27;19(2):1527-43. doi: 10.3390/molecules19021527.

Abstract

The title compound 1-exo (with minor amounts of its C8 epimer 1-endo) was prepared by Wolff-Kishner reduction of the cycloadduct of 1,3-cyclohexadiene and cyclopropylketene. The [1,3]-migration product 2-endo was synthesized by efficient selective cyclopropanation of endo-5-vinylbicyclo[2.2.2]oct-2-ene at the exocyclic π-bond. Gas phase thermal reactions of 1-exo afforded C8 epimerization to 1-endo, [1,3]- migrations to 2-exo and 2-endo, direct fragmentation to cyclohexadiene and vinylcyclopropane, and CPC rearrangement in the following relative kinetic order: kep > k13 > kf > kCPC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bridged Bicyclo Compounds / chemistry*
  • Cyclohexenes / chemical synthesis
  • Cyclohexenes / chemistry*
  • Gases / chemical synthesis
  • Gases / chemistry*
  • Kinetics
  • Models, Molecular
  • Phase Transition*

Substances

  • Bridged Bicyclo Compounds
  • Cyclohexenes
  • Gases
  • exo-8-cyclopropyl-bicyclo(4.2.0)oct-2-ene
  • 1,3-cyclohexadiene