20020-13-7Relevant academic research and scientific papers
Structure of N,4-dinitroaniline and its complex with sulfolane at 85 K; on the proton donor-acceptor affinity of the primary nitramine (HNNO2) group
Zaleski,Daszkiewicz,Kyziot
, p. 109 - 115 (2002)
The NNO2 group of the title compound is significantly less twisted with respect to the aromatic ring in comparison to a typical secondary nitramine. The amide nitrogen is trigonally hybridized. The nitramino group is almost planar. The C-C-N-N
Acidity and basicity of primary N-phenylnitramines: Catalytic effect of protons on the nitramine rearrangement
Daszkiewicz, Zdzislaw,Spaleniak, Grzegorz,Kyziol, Janusz B.
, p. 115 - 122 (2007/10/03)
Para-substituted N-phenylnitramines were prepared either by oxidation of diazonium salts or by nitration under alkaline or acidic conditions. Isotopic [15N-NO2] labelling indicated that the bands characteristic of the N-nitro group appear in the 1318-1323 and 1585-1607 cm-1 regions. In the nitrogen NMR spectra, the nitramino group gives two resonances at -193 ± 3 (NH) and -32 ± 3 ppm (NO2). The chemical shifts in proton and carbon NMR spectra are predictable, based on increments and the additivity rule. The spectral data indicate the lack of conjugation between the nitramino group and another substituent bound to the ring. It seems to contradict the well-known fact that substituents strongly (ρ = 4) influence the rate of nitramine rearrangement. The acidities of primary N-phenylnitramines (3.77 A B ≈ 21) are extremely low. Consequently, addition of protons to an intact nitramine molecule, as the preliminary step of the rearrangement, seems to be improbable. Migration of the N-nitro group precedes protonation; the latter process facilitates transformation of intermediates into stable final products. Copyright
