Enantioselective Synthesis of Halogenated Adamantane-Based Amino Acid Derivatives via Rhodium-Catalyzed C–H Bond Amination

A new set of reaction conditions for the rhodium-catalyzed enantioselective C-H bond amination of 1,3-disubstituted adamantanes has been developed. An amino acid derivative bearing a bromide substituent was obtained in up to 90% ee through enantioselective desymmetrization. The protocol was also applicable to substrates bearing chloride, methyl, and butyl substituents, affording the corresponding amino acid derivatives in >80% ee. The bromide-containing product was further converted into chloride and azide derivatives, demonstrating its utility as a chiral building block.