A simple and efficient synthesis of 8-methyl-3,8-diazabicyclo[3.2.1]octane (azatropane) and 3-substituted azatropanes therefrom using pyroglutamic acid

8-Methyl-3,8-diazabicyclo[3.2.1]octane (3-azatropane) is synthesized efficiently from pyroglutamic acid making use of amide activation. The key step of the synthesis involves reduction and cyclization of a nitroenamine intermediate. Several 3-substituted analogues of this azatropane were also synthesized via this methodology and evaluated for their affinity at D2 and 5-HT2A receptors.