Conformational and structural analysis of exocyclic olefins and ketimines by multinuclear magnetic resonance

Magn Reson Chem. 2008 Oct;46(10):907-12. doi: 10.1002/mrc.2259.

Abstract

The (1)H, (13)C, and (15)N NMR spectra of 5 exocyclic alkenes and 15 different ketimines obtained from cyclohexanone and derivatives using benzyl bromide and primary amines-are analyzed. Relative stereochemical and preferential conformations are determined by analyzing both the homonuclear coupling and the chemical shifts of the protons and carbon atoms in the aliphatic rings, which are directly related to the geometry of the double bond and the steric and electronic effects of the exocyclic group. In addition, the racemic mixture of the N-(4-methylcyclohexylidene)pyridine-3-amine derivative is resolved.

MeSH terms

  • Cyclohexanones / chemistry
  • Cycloparaffins / analysis*
  • Imines / analysis*
  • Models, Molecular
  • Molecular Structure
  • Nuclear Magnetic Resonance, Biomolecular / methods*
  • Reference Standards
  • Sensitivity and Specificity
  • Stereoisomerism

Substances

  • Cyclohexanones
  • Cycloparaffins
  • Imines
  • cyclohexanone