The C2-symmetrical 2,8- and 4,10-diimidazo-methano dibenzo-diazocines have been successfully synthesized and structurally characterized. The single crystal structures of 2,8- and 4,10-diimidazo-methano dibenzo-diazocines are the first structurally characterized heterocyclic ring systems attached to the methano dibenzo-diazocines. Notably, the 2,8- and 4,10-diimidazo-methano dibenzo-diazocines are isolated without any additional groups (on benzene rings) by the condensation of ortho or para imidazo-aniline with paraformaldehyde in trifluoroacetic acid. The diimidazo-methano dibenzo-diazocines have been fully characterized. Furthermore, these newly prepared nitrogen rich heterocyclic compounds have been subjected to selective alkyl or aralkylation reactions. The alkyl or aralkyl substituted products of diimidazo-methano dibenzo-diazocines have been fully characterized. Besides, the single crystal X-ray structures of methyl, isopropyl and 2-picolyl substituted derivatives of 4,10-diimidazo-methano dibenzo-diazocines have been reported for the first time. © 2014 the Partner Organisations.