188439-79-4Relevant articles and documents
Synthesis and X-ray structural determination of new aniline derivatives of 2,4,6,8-tetraazabicyclo[3.3.0]octanes; anomeric effect in N-C-N moiety and implications of solvent polarity on 1H-NMR patterns
Kakanejadifard, Ali,Farnia, S. Morteza F.
, p. 2551 - 2556 (1997)
The condensation of aniline with glyoxal and formaldehyde in stoichiometric ratio, leads to 2,4,6,8-tetraphenyl-2,4,6,8-tetraazabicyclo[3.3.0]octane (1f) with formic acid as catalyst. Nine substituted derivatives of 1f have been prepared in high yield by this synthetic method. X-ray analysis revealed the existence of an anomeric effect, n(N) → σ*(C-N) in N-C-N moieties manifested by reduction in N-pyramidality and short C-N bond lengths. Moreover, 1H-NMR studies showed the dependency of methylenic protons splitting pattern on solvent polarity.