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Primary Nitramines Related to Nitroglycerine: 1-Nitramino-2,3-dinitroxypropane and 1,2,3-Trinitraminopropane

Altenburg T., Klapötke T. M., Penger A.

Central European Journal of Energetic Materials

2009

Vol. 6, nr 3-4

255-275

The title compounds 1-nitramino-2,3-dinitroxypropane (NG-N1) and 1,2,3-trinitraminopropane (NG-N3) were formed by multi-step reaction from the corresponding amine. Both compounds were fully characterized by means of multinuclear NMR (1 H, 13 C, 14 N) N), vibrational spectroscopy, elemental analysis and mass spectrometry. For prediction of the energetic properties ΔHc values are determined by oxygen bomb calorimetry and validated by quantum theoretical methods. Both compounds are superior in their performance data to nitroglycerine (NG) and pentaerythritol tetranitrate (PETN). In comparison to nitroglycerine the sensitivities towards mechanical stimuli is greatly reduced. X-ray diffraction elucidated the molecular structure of both compounds. NG-N1 crystallizes in the monoclinic space group P21 with a density of 1.799 g/cm(3), NG-N3 in the orthorhombic space group Pnma with a density of 1.783 g/cm(3). The thermal behavior and long term stabilities were checked using differential scanning calorimetry and thermogravimetric measurements. NG-N1, shows for primary nitramines, exceptional stability in the molten phase making this compound suitable for melt-cast application (Tmp: 65 C, Tdec: 170 C).

Predominance of (E)-1,2-Di(pyridin-2-yl)ethene-1,2-diol over 2-Hydroxy-1,2-di(pyridin-2-yl)ethanone in Solution

Gawinecki R., Ośmiałowski B., Kolehmainen E.

Polish Journal of Chemistry

2003

Vol. 77 / nr 11

1411-1417

1H, 13C and 15N NMR spectra, supported by the GIAO/DFT calculated (B3LYP/6- 311G//RHF/3-21G) 13C and 15N (B3LYP/6-31++G**//RHF/3-21G) NMR chemical shifts, show that (E)-1,2-di(pyridin-2-yl)ethene-1,2-diol (OO3) is the only tautomer present in chloroform solution. MP2/6-31G**//RHF/6-31G** and MP2/6-31G** ab initio calculations confirm that this perfectly planar form is really more stable than 2-hydroxy-1,2-di(pyridin-2-yl)ethanone (OK1, OK2 and OK3) and other isomeric dimers of pyridine-2-carboxaldehyde. The strong intramolecular hydrogen bonds are responsible for high stability of (E)-1,2-di(pyridin-2-yl)ethene-1,2-diol (the conjugation in the molecule is of minor importance).