Conformational analysis of ketoximes by the application of carbon-13 nuclear magnetic resonance spectroscopy

Abstract

The carbon-13 chemical shifts for a number of relatively rigid ketoximes are presented. It is shown that the chemical shift difference, Δδ (syn—anti), for the carbons α to the oxime carbon depends on the dihedral angle between the C=N and C α —H bonds. This stereochemical dependence is then used to determine the preferred conformation of substituted cyclohexanone oximes.