Some nitro-substituted triazole-furazan derivatives are considered as potential candidates for high energy density compounds through quantum chemical treatment. Their geometric and electronic structures,band gap,therm...Some nitro-substituted triazole-furazan derivatives are considered as potential candidates for high energy density compounds through quantum chemical treatment. Their geometric and electronic structures,band gap,thermodynamic properties and detonation properties were studied using the density functional theory at the B3 LYP /6- 311 + G**level. The calculated energy of explosion,density,and detonation properties of model compounds were comparable to 1,3,5-trinitro-1,3,5-triazinane( RDX) and 1,3,5,7-tetranitro-1,3,5,7-tetrazocane( HMX). The heats of formation and bond dissociation energy were also analysed to understand the nature of thermal stabilities and the trigger bond in the pyrolysis process.展开更多
UHF-SCF-AM1 MO calculations were performed for two kinds of pyrolysis reactions of seven nitro derivatives of methylbenzene(homolysis reactions by the rupture of bond C-NO_2 into radicals and isomerization reactions ...UHF-SCF-AM1 MO calculations were performed for two kinds of pyrolysis reactions of seven nitro derivatives of methylbenzene(homolysis reactions by the rupture of bond C-NO_2 into radicals and isomerization reactions in the way of methyl H transferring to the ortho nitro O atom). The molecular geometries of the reactants, the transition states and the products of the fourteen reactions were fully optimized. The activation energies for these two kinds of reactions have been obtained. The results indicate that this category of compounds is more easily pyrolyzed by being initiated via isomerization reactions. A parallel relationship exists between the activation energy of the isomerization reactions and the impact sensitivity of the seven titled compounds.展开更多
The title compound C18H16N4O3 (Mr = 336.35) has been synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. The Schiff base compound is a derivative of 4-aminoantipyrine. As expect...The title compound C18H16N4O3 (Mr = 336.35) has been synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. The Schiff base compound is a derivative of 4-aminoantipyrine. As expected, the molecular structure adopts a trans configuration about the central C=N double bond. It crystallizes in orthorhombic, space group P2dc with a = 7.632(1), b = 7.816(1), c = 28.082(5) A,β = 96.18(1)°, V= 1665.48(51) A^3, Z= 4, Dc = 1.341 g/cm^3, F(000) = 704,μ = 0.094 mm^-1, the final R = 0.0448 and wR = 0.1058. Of the total 3748 collections, 3105 were unique. In the molecule there exist two different planes of pyrazoline and C(11)-C(16) phenyl ring, which are approximately coplanar (r.m.s. de deviation from the combined mean plane is 0.03 A) with the dihedral angle between them of 9.8%.展开更多
Poly ethylene glycols (PEG-200, 400, 600, 4000 and 6000) supported reactions were conducted with certain α, β-unsaturated acids in presence of metal nitrates under solvent free (solid state) and mineral acid free co...Poly ethylene glycols (PEG-200, 400, 600, 4000 and 6000) supported reactions were conducted with certain α, β-unsaturated acids in presence of metal nitrates under solvent free (solid state) and mineral acid free conditions. The reactants were ground in a mortar with a pestle for about 30 minutes. The aromatic acids underwent nitro decarboxylation and afforded β-nitro styrene derivatives in very good yield while α, β-unsaturated aliphatic carboxylic acids gave corresponding nitro derivatives. Addition of PEG accelerated rate of the reaction enormously. Reaction times substantially decreased from several hours to few minutes followed by highly significant increase in the product yield. Among the several PEGs PEG-300 has been found to be much more effective than other PEGs.展开更多
The DFT-B3LPY method, with basis set 6-31G*, is employed to calculate the structures and properties for aromatic explosives containing -NO 2 groups, nitro derivatives of benzene and nitro derivatives of aminobenzene. ...The DFT-B3LPY method, with basis set 6-31G*, is employed to calculate the structures and properties for aromatic explosives containing -NO 2 groups, nitro derivatives of benzene and nitro derivatives of aminobenzene. It is found that there is a parallel relationship between experimental impact sensitivity and bond order of the weakest C-NO 2 bond in a molecule in each series. Previously, based on semiempirical MO calculations, "the principle of the smallest bond order (PSBO) " has been proposed by us to identify the relative magnitudes of impact sensitivity of a series of explosive compounds with similar molecular structures. Here, PSBO is verified powerfully from the ab initio calculations for title compounds.展开更多
文摘Some nitro-substituted triazole-furazan derivatives are considered as potential candidates for high energy density compounds through quantum chemical treatment. Their geometric and electronic structures,band gap,thermodynamic properties and detonation properties were studied using the density functional theory at the B3 LYP /6- 311 + G**level. The calculated energy of explosion,density,and detonation properties of model compounds were comparable to 1,3,5-trinitro-1,3,5-triazinane( RDX) and 1,3,5,7-tetranitro-1,3,5,7-tetrazocane( HMX). The heats of formation and bond dissociation energy were also analysed to understand the nature of thermal stabilities and the trigger bond in the pyrolysis process.
文摘UHF-SCF-AM1 MO calculations were performed for two kinds of pyrolysis reactions of seven nitro derivatives of methylbenzene(homolysis reactions by the rupture of bond C-NO_2 into radicals and isomerization reactions in the way of methyl H transferring to the ortho nitro O atom). The molecular geometries of the reactants, the transition states and the products of the fourteen reactions were fully optimized. The activation energies for these two kinds of reactions have been obtained. The results indicate that this category of compounds is more easily pyrolyzed by being initiated via isomerization reactions. A parallel relationship exists between the activation energy of the isomerization reactions and the impact sensitivity of the seven titled compounds.
文摘The title compound C18H16N4O3 (Mr = 336.35) has been synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. The Schiff base compound is a derivative of 4-aminoantipyrine. As expected, the molecular structure adopts a trans configuration about the central C=N double bond. It crystallizes in orthorhombic, space group P2dc with a = 7.632(1), b = 7.816(1), c = 28.082(5) A,β = 96.18(1)°, V= 1665.48(51) A^3, Z= 4, Dc = 1.341 g/cm^3, F(000) = 704,μ = 0.094 mm^-1, the final R = 0.0448 and wR = 0.1058. Of the total 3748 collections, 3105 were unique. In the molecule there exist two different planes of pyrazoline and C(11)-C(16) phenyl ring, which are approximately coplanar (r.m.s. de deviation from the combined mean plane is 0.03 A) with the dihedral angle between them of 9.8%.
文摘Poly ethylene glycols (PEG-200, 400, 600, 4000 and 6000) supported reactions were conducted with certain α, β-unsaturated acids in presence of metal nitrates under solvent free (solid state) and mineral acid free conditions. The reactants were ground in a mortar with a pestle for about 30 minutes. The aromatic acids underwent nitro decarboxylation and afforded β-nitro styrene derivatives in very good yield while α, β-unsaturated aliphatic carboxylic acids gave corresponding nitro derivatives. Addition of PEG accelerated rate of the reaction enormously. Reaction times substantially decreased from several hours to few minutes followed by highly significant increase in the product yield. Among the several PEGs PEG-300 has been found to be much more effective than other PEGs.
文摘The DFT-B3LPY method, with basis set 6-31G*, is employed to calculate the structures and properties for aromatic explosives containing -NO 2 groups, nitro derivatives of benzene and nitro derivatives of aminobenzene. It is found that there is a parallel relationship between experimental impact sensitivity and bond order of the weakest C-NO 2 bond in a molecule in each series. Previously, based on semiempirical MO calculations, "the principle of the smallest bond order (PSBO) " has been proposed by us to identify the relative magnitudes of impact sensitivity of a series of explosive compounds with similar molecular structures. Here, PSBO is verified powerfully from the ab initio calculations for title compounds.