The hydrogen bond acidity and other descriptors for oximes

The solvation descriptors for cyclohexanone oxime and acetone oxime have been obtained from measurements on water-solvent partitions, and gas-liquid chromatographic retention data. These yield values of 0.33 and 0.37 for the Abraham hydrogen bond acidity, A, in reasonable agreement with a value of 0.37 for cyclohexanone oxime obtained by our recent NMR method. The other descriptors E, S, B, L and V have also been obtained for cyclohexanone oxime and acetone oxime, and have been estimated for a number of other oximes as well. The value for A, the overall or effective hydrogen bond acidity of the oximes is reasonably close to the 1 : 1 hydrogen bond acidity, alpha(H)(2) = 0.39 to 0.46, that can be deduced from previous literature measurements on oximes, and to the 1 : 1 hydrogen bond acidity, alpha(H)(2) = 0.43 for another NOH compound, N,N-dibenzylhydroxylamine, that again can be deduced from literature measurements.