Carbon-13 nuclear magnetic resonance study of the alpha- and beta- isomers of methadol and acetylmethadol hydrochlorides.

The 13C-NMR spectra reported in these studies give direct evidence for the presence of two contributing conformers for alpha-methadol hydrochloride, alpha-acetylmethadol hydrochloride and beta-acetylmethadol hydrochloride. Indirect evidence is also available for the presence of more than one conformer for beta-methadol hydrochloride. However, in order to be more descriptive about the structures of the conformers, it is necessary to obtain 13C-NMR spectra that have a higher degree of resolution than is available from our present NMR system. Such systems are available, and plans are currently in progress to obtain 13C-NMR spectra or these compounds at high enough magnetic fields and low enough temperatures to give us the necessary data.