Synthesis of optically active fluoroadamantane derivative having different substituents on its tert-carbons and its use as a non-racemizable source for new optically active adamantane derivatives

Enantiomerically pure methyl 3-fluoro-5-methyladamantane-1-carboxylate was obtained by the separation of its racemate, which was prepared from methyladamantane-1-carboxylate in three steps in 86% overall yield. From the resulting pure enantiomers, a new optically active adamantane compound was prepared by the substitution of a fluorine atom with a phenyl group. Both enantiomers of 3-amino-5-methyladamantane-1-carbooxylic acid were also prepared.