Bridgehead intermediates in organic synthesis. A reproducible synthesis of adamantane-containing compounds

Compounds containing the adamantane subunit have long been of interest to chemists due to the rigid structure and well-defined substitution chemistry of adamantane.l The discovery of the potent antiviral activity of amantadine (1-aminoadamantane) and rimantadine (a-methyl-l-adamantylmethylamine) has stimulated interest in the synthesis of adamantane-containing compounds.2 The significant neuroprotective properties of the NMDA antagonist memantine3 (l-amino-3,5-dimethyladamantane) have also prompted interest in adamantane synthesis