Synthesis and computational analysis of conformationally restricted [3.2.2]- and [3.2.1]-3-azabicyclic diamines

•Expeditious synthesis of five unknown bicyclic [3.2.n] diamines (n=1 and 2)•In silico analysis flexibility reveals low barrier for boat–chair interconversion.•In silico analysis reveals substituents influence conformation in [3.2.2] scaffold.•Substantial overlap with low energy conformations of 1,3-diaminopropane.