Intermolecular hydrogen bonding oximes

The enthalpy of reaction 38 is ca 13 kJ mol" for the case of cyclohexanone wherein R R = —(CH2)5—. This difference is compatible with intermolecular hydrogen bonding as would be found for the benzoquinone oxime tautomer. In order to understand the energetics of reaction 39, we derived the solid phase enthalpy of formation of nitrosobenzene... 

Oximes show strong intermolecular hydrogen bonding, in nonpolar solvents, which affects the H NMR chemical shifts and coupling constants. The influence of this interaction on the conformational equilibrium and on some selected coupling constants 7cf and Jcp) was evaluated. Thus the H and C NMR spectra in different solvents were obtained. Both 7hf and Jcf are sensitive to the F—C—C=N orientation (Tables 18 and 19). 

The structures of some phosphorylated glyoxal oximes have been examined by NMR and IR spectroscopic methods. These compounds may exist as two types of intramolec-ularly hydrogen-bonded species (38, 39) or as intermolecularly hydrogen bonded molecules (not shown). It was concluded, on the basis of spectroscopic studies, that the -form. 

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