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

✍ Scribed by Ali Kakanejadifard; S.Morteza F. Farnia

• Publisher: Elsevier Science
• Year: 1997
• Tongue: French
• Weight: 305 KB
• Volume: 53
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(96)01143-x

✦ Synopsis

The condensation of aniline with glyoxal and formaldehyde in stoichiometric ratio, leads to 2,4,6,8-tetraphenyl-2,4,6,8-tetraazabicyclol3.3.0]octane (lf) with formic acid as catalyst. Nine substituted derivatives of If have been prepared in high yield by this synthetic method. X-ray analysis revealed the existence of an anomeric effect, n N ~ o 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.