Synthesis of a Conformationally Rigid Analogue of 2-Aminoadipic Acid ­Containing an 8-Azabicyclo[3.2.1]octane Skeleton

A new, conformationally rigid analogue of 2-amino­adipic acid, 8-[(benzyloxy)carbonyl]-3-methylene-8-azabicyclo[3.2.1]octane-1,5-dicarboxylic acid, is synthesized from dimethyl rac-2,5-dibromohexanedioate. The key steps involve alkylation-cyclization of 1-benzyl 2,5-dimethyl pyrrolidine-1,2,5-tricarboxylate with 3-chloro-2-(chloromethyl)prop-1-ene to yield the 8-azabicyclo[3.2.1]octane skeleton.