Studies of the synthesis, protonation and decomposition of 2,4,6,8,10,12-hexabenzyl-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.05,9.03,11]dodecane (HBIW)

Abstract
Reaction of glyoxal with benzylamine or with substituted benzylamines leads to the cage structure 3. The X-ray crystal structure of 3c formed from 4-chlorobenzylamine is reported. 1H and 13C NMR spectra of 3a–j have been measured. Changes in spectra in the presence of acid indicate successive reaction to give mono- and di-protonated species, 4 and 5 respectively, in which the added protons bridge two nitrogen atoms. The kinetics of the decomposition of 3a in aqueous acetonitrile are compatible with two competing pathways involving reaction of the protonated form with either water or more acid.