PREPARATION AND C-13 NMR SPECTROSCOPIC STUDY OF DISUBSTITUTED ADAMANTANE-1,3-DIMETHYLDIYL DICATIONS

A series of substituted adamantane-1,3-dimethyldiyl dications 5 has been prepared by the ionization of alpha,alpha,alpha',alpha'-tetrasubstituted-1,3-adamantanedimethyl diols 6 in superacidic media. The dications were stable with groups such as phenyl and methyl, however, unstable with cyclopropyl groups. The C-13 NMR spectroscopic study of the obtained dications clearly indicates that the positive charges are more delocalized into the substituents due to the close proximity of the cationic centers through the adamantyl cage. These studies are informative in probing cage compounds with multiply-charged centers.