Multigram-Scale Access to 2-Oxaadamantan-1-amine and 2-Oxaadamantan-1-ol via Optimized Synthesis of Bicyclo[3.3.1]nonane-3,7-dione

Practical, tens-of-grams-scale access to 2-oxaadamantan-1-amine and 2-oxaadamantan-1-ol – two overlooked heteroadamantane building blocks of interest for medicinal chemistry – has been achieved through optimization and scale-up of existing literature protocols. The key precursor, bicyclo[3.3.1]nonane-3,7-dione, and both target compounds are obtained in good overall yields using straightforward procedures and standard reagents. Notably, 2-oxaadamantan-1-amine is an exceptionally stable N,O-acetal, in stark contrast to the high hydrolytic lability usually seen in this compound class.