Collect. Czech. Chem. Commun. 1990, 55, 452-459

29Si and 13C nmr spectra of trimethylsiloxy and hydroxy adamantanes reinvestigated at low concentration in deuteriochloroform solutions

Jan Schraml and Jan Čermák

Institute of Chemical Process Fundamentals, Czechoslovak Academy of Sciences, 165 02 Prague 6-Suchdol


29Si and 13C NMR chemical shifts are reported for mono- and bis(trimethylsiloxy)adamantanes as well as for mono- and dihydroxyadamantanes dissolved in deuteriochloroform. The chloroform induced changes in 29Si and 13C chemical shifts can be qualitatively accounted for by hydrogen-bonding considering basicity and solvent accessibility of oxygen atoms in the solute molecules. The steric effects observed on the 29Si shifts are not due to an interaction of the terminal hydrogen atoms of the trimethylsilyl groups but are due to proximity of two oxygen atoms on one cyclohexane ring of the adamantane skeleton.