13C NMR DETERMINATION OF THE CONFORMATIONAL EQUILIBRIA IN THE ACETATES, BENZOATES AND N-PHENYLCARBAMATES OF 1-METHYLCYCLOHEXANOL AND CYCLOHEXANOL

Article abstract of DOI:10.1016/S0040-4020(01)87406-8

Thermodynamic parameters for the conformational equilibria in the acetates, benzoates and N-phenylcarbamates of 1-methylcyclohexanol and cyclohexanol have been determined using low temperature natural abundance 13C nmr, from which -ΔG⁰ values at room temperature and above are obtained.Good agreement between these values and those determined at the higher temperatures using Eliel's method is found, providing care is exercised in correcting the chemical shifts of the model compounds used to the shifts of pure conformers of the 1,1-disubstituted cyclohexanes.Calculated values for -ΔG⁰ agree reasonably with experimental values with the exception of that for the 1-methylcyclohexyl N-phenylcarbamate.The effect of non polar solvent changes is minimal, but greater for CD3OD.