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1

On the Mechanism of Thermal Decomposition of 1,1-Diamino-2,2-dinitroethene (FOX-7) and its Cyclic Derivatives

Krisyuk Boris E., Zakharov Viktor V., Chukanov Nikita V.

Central European Journal of Energetic Materials

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2020

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Vol. 17, no. 1

20--30

EN

The thermal decomposition of 1,1-diamino-2,2-dinitroethene (I) and its cyclic derivatives 2-(dinitromethylene)-1,3-diazacyclopentane (II), 2-(dinitromethylene)-1,3-diazacyclohexane (III) and 2-(dinitromethylene)-1,3-diazacycloheptane (IV) was investigated by quantum chemistry methods (PBE/cc-pVDZ), as well as DSC and TG. According to both the theoretical and experimental data, the thermal stability of compounds I-IV increases in the sequence IV < I ≈ III < II.

2

Synthesis, Crystal Structure, Characterization and Ab Initio Calculations on a Dicycle Pyrazoline Derivative

Guo H. M., Zhang J., Zhao P. S., Jian F. F.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 2

263-274

EN

A dicycle pyrazoline derivative, 1-acetyl-5-(2-chlorophenyl)-3,4-(a-o-chlorotolylene-cyclohexano) pyrazoline, was synthesized and characterized by elemental analysis, IR, UV-Vis, fluorescence spectra and X-ray single crystal diffraction. Quantum chemical calculations were performed by using B3LYP and HF methods with 6-311G* basis set. Both methods can well simulate the molecular structure. Vibrational frequencies were predicted, assigned and compared with the experimental values, which suggest that both methods can only approximatively predict the vibrational frequencies. Electronic absorption spectra predicted by B3LYP/6-311G asterisk operator method well corresponding with the experimental data and natural bond orbital analyses indicate that the absorption bands are mainly derived from the contribution of n → pi asterisk operator and pi → pi asterisk operator transitions. For the system studied here, HF/6-311G asterisk operator method cannot be used to obtain the electronic absorption spectra. On the basis of vibrational analysis, the thermodynamic properties of the title compound at different temperature have been calculated, revealing the correlations between C0 p,m S 0 m, H0 m and temperature.

3

Molecular Interactions and Structure of H-Bonded Complexes of Bifunctional Nitrogen-Containing Molecules

Bureiko S. F., Kucherov S. Yu., Schreiber V. M.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 5

771-785

EN

The results of experimental studies and quantum chemical calculations of vibrational spectra and struc ture of H-bonded complexes formed by N-containing bases 3,5-dimethylpyrazole, diphenyltriazene and diphenylformamidine with carboxylic acids and HHal are discussed. The IR spectra of solutions in CH2Cl2 and CCl4 and low temperature NMR spectra show the existence of equilibrium between monomers and cyclic selfassociates of the mole ules studied. Under the interaction with weak carboxylic acids the complexes have molecular structure with two H-bonds NH…O=C and OH…N, and the interaction with strong acids results information of cyclic H-bonded ionic pairs with proton transfer to the N atom of the base. The proton transfer in solution was observed also for open complexes with HHal. The quantum chemical DFT calulations in harmonic and an harmonic approximations confirm the formation of cyclic complexes, while the proton transfer along the OH…N bridge was supported for the complexes with strongest ac ids. It was shown that the use of variational multidimensional an harmonic approach is the most preferable for calculations of the high-frequency XH stretch in systems where the corresponding normal mode is less characteristic and involves motions of many atoms.

4

Crystal structure and spectroscopic properties of 4-acetaminopyridine and its protonated form

Koleva B.B., Nikolova R., Tchapkanov A., Kolev T., Mayer-Figge H., Spiteller M., Sheldrick W.S.

Polish Journal of Chemical Technology

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2009

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Vol. 11, nr 3

35-40

EN

4-Acetaminopyridine dihydrate and its protonated form, stabilized as the hydrochloride salt have been synthesized and spectroscopic elucidated in solution and in the solid-state by means of the inear-polarized solid state IR-spectroscopy (IR-LD), UV-spectroscopy, TGA, DSC, and the positive and negative ESI MS. Quantum chemical calculations were used to obtain the electronic structure, vibrational data and the electronic spectra. The spectroscopic and theoretical data are compared with the structure of the first compound obtained by single crystal X-ray diffraction. The effect of Npy protonation on the optical and magnetic properties of a 4-acetaminopyridine is discussed.

5

Synthesis, Characterization, Crystal Structure and Quantum Chemical Studies on N-Dimethyl-N'-phenyl-thiocarbamide

Zhao P. S., Qin Y. Q., Zhang J., Jian F. F.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 11

2153-2165

EN

The title compound of N-dimethyl-Nc-phenyl-thiocarbamide was synthesized and characterized by elemental analysis, IR, NMR, electronic spectra and X-ray single crystal diffraction. Quantum chemical calculations were performed by using B3LYP and HF methods with 6-311G** basis set. Both the methods well simulate the molecular structure. Vibrational frequencies were predicted, assigned and compared with the experimental values, which suggest that both methods can only predict the vibrational frequencies approximatively. The nuclear magnetic shieldings were predicted by using GIAO method and compared with experiment. The results show that, for the title compound, B3LYP/6-311G** method better predicts the 13C NMR spectra than HF/6-311G**, whereas HF/6-311G** better predicts the 1H NMR spectra than B3LYP/6-311G**. Electronic absorption spectra predicted by B3LYP/6-311G** method are closer to the experimental data and natural bond orbital analyses indicate that the absorption bands are mainly from the contribution of n → pi* and pi → pi* transitions. For the system studied here, HF/6-311G** method can not be used to obtain the electronic absorption spectra. On the basis of vibrational analyses, the thermodynamic properties of the title compound at different temperatures have been calculated, revealing the correlations between Cp,m 0 , Sm 0 , Hm 0 and temperatures.

6

Regioselective Reaction of 2-Hydroxyliminoimidazolidine-O-sulfonate with Benzyl Bromides

Sączewski J., Gdaniec M.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 11

2107-2113

EN

Triethylaminium 2-hydroxylaminoimidazolidine-O-sulfonate was alkylated at the exocyclic N2 nitrogen atom of the 2-iminoimidazolidine moiety to give 2-benzyl-2- hydro-xylamino-4,5-dihydroimidazolium-O-sulfonates. The structure of products was confirmed by X-ray crystallographic analysis. The obtained compounds upon treatment with carbon disulfide were further converted into bis(2-benzyl amino- 4,5-dihydroimidazol-1-yl)methanethiones.

7

Crystal Structure and Quantum Chemical Calculations on o-Hydroxyacetophenone Phenylhydrazone

Jian F. F., Li Y. F., Yang X. Y., Zhao P. S., Xiao H. L.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 8

1597-1597

EN

o-Hydroxyacetophenone phenylhydrazone has been synthesized and characterized by elemental analysis, IR and electronic spectroscopy. The X-ray crystal structure study shows that the compound contains two crystallographically independent molecules in the asymmetric unit and crystallizes in the monoclinic system, space group P21/c, with Mr =226.27 (C14H14N2O), a = 13.433(3), b = 10.738(2), c = 18.351(7) Capital A, beta = 114.44(2)°, V = 2409.8(12) Capital A 3, Z = 8, Dc = 1.247 Mg/m3, F (000) = 960, mi (Mo K) = 0.080 mm–1, R = 0.0638, wR = 0.1535. Ab initio calculations of the structure, atomic charge distributions, natural bond orbital analysis and thermodynamic functions of the title compound were performed at HF/6-311G** and B3LYP/6-311G** levels of theory. Electronic absorption spectra were calculated by the time-dependent density functional theory (TD-DFT). Vibrational frequencies were predicted, as signed and compared with the experimental values. The calculation of the second order optical nonlinearity was carried out and the molecular hyperpolarizability of 3.332×10–30 esu was predicted.

8

Computational Study of Deprotonation of Cyclopropa-Fused Quinones

Eckert-Maksić M., Glasovac Z.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 5-6

1109-1121

EN

The acidities of cyclopropa-fused quinones 1H–3H were calculated by employing MP2 and B3LYP methods utilizing the 6-31+G(d) basis set. Analysis of the results shows that all three isomers are considerably more acidic than the previously studied cyclopropabenzene. It is also shown that acidity of1His significantly higher than acidity of 2H and 3H. The acidity ordering of the studied species is rationalized by a triadic formula, which is capable of delineating the initial, intermediate and the final state effects in the deprotonation process. It is found that the ordering of the calculated proton affinities is mainly determined by an interplay of two terms: Koopmans’ionization energy and the relaxation energy.

9

Reakcje [2+4] cykloaddycji cyklopentadienu i furanu z wybranymi β-nitrostyrenami w świetle obliczeń PM3 i PM3/COSMO

Bujak M., Barański A.

Czasopismo Techniczne. Chemia

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2004

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R. 101, z. 1-Ch

13-29

PL

Niniejsza praca dotyczy kwantowochemicznych studiów nad reakcją [2+4] cykloaddycji wybranych β-nitrostyrenów z cyklopentadienem i furanem. Obliczenia prowadzono za pomocą metody PM3 i PM3/COSMO dla fazy gazowej oraz symulowanej obecności medium dielektrycznego.

EN

The PM3 and PM3/COSMO calculations for [2+4] cycloaddition reactions of some β-nitrostyrenes to cyclopentadiene and furane were carried out. Calculations were performed for the gas phase and for dielectric continuum with ε = 2,4 and 37,8.

10

Quantum-Chemical Calculations of First-Order Hyperpolarizability of Epoxy Oligomers with Chromophore in the main Chain

Balakina M., Ilyazov M. F., Zuev M. B.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 9

1199-1209

EN

Results of quantum-chemical calculations of first hyperpolarizabilities for a number of epoxy oligomers with nonlinear optical (NLO) chromophores incorporated into the main chain as a side group are presented. These oligomers simulate the internode chains of cross-linked NLO materials, which are the most promising candidates for application in optoelectronics. The attempt is made to establish a relationship between the hyperpolarizability and the conformation of the bearing chain in the vicinity of the chromophore. The structure and conformation of the oligomer chain are shown to affect significantly the longitudinal hyperpolarizability of the chromophore. Some recommendations are given to obtain hyperpolarizability values optimal for the studied molecular systems.

11

New Photosensitive Methacrylate Monomers with 4-Aminoazobenzene Type Chromophore Group

Janik R., Kucharski S., Kubaińska A., Łyko B.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 2

241-252

EN

Photosensitive methacrylate monomers, derivatives of azobenzene, were synthesized. The route of syntheses was based on coupling of diazonium salts of sulfathiazole, sulfomethoxazole, sulfadiazine, 4-aminobenzoic acid and 4-nitroaniline with N-alkyl-N- [2-(methacryloyloxy)ethyl]aniline. The trans cis isomerization of the monomers in DMSO solution was investigated by UV-VIS spectroscopy recording their spectra during illumination and thermal recovery periods. It was found that except for nitro derivatives the yield of trans-cis isomerization was ca. 50% and that the reverse reaction was a result of thermal relaxation. The spectroscopic studies were accompanied by quantum chemical calculations.

12

Dipole Moment, Molar Kerr Constant, Crystal and Molecular Structure of 3-Chloro-N-methyl-N-nitroaniline

Prezhdo V., Bykova A. S., Głowiak T., Prezhdo O. V., Daszkiewicz Z., Kyzioł J. B.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 5

707-718

EN

Dipole moment, molar Kerr constant, crystal and molecular structure of m- ClC6H4N(CH3)NO2 (or C7H7ClN2O2) are studied. Comparison the data obtained by dipole moment and molar Kerr constant measurement, X-ray crystallographic investigation and quantum-chemical calculation show that the molecule contains a planar NNO2 nitroamino group which is twisted around the N-Cphenyl bond by ca 61.4_ from the plane of the aromatic ring. The structural data are compared with the data for p- ClC6H4N(CH3)NO2 and the influence of the substituent on the structural parameters of the molecule is established.

13

Selective synthesis of 1,3-di- and 1,3,5-trisubstituted tetrazolium salts by tert-butylation of tetrazole, 1- and 5-monosubstituted tetrazoles, isomerization of 1,3-disubstituted salts to 1,4-salts

Gaponik P.N., Voitekhovich S.V., Maruda I.I., Kulak A.A., Ivashkevich O.A.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 10

2247-2253

EN

Tetrazole and its 1- and 5-monosubstituted derivatives are found to react with tert-butyl alcohol in 72% perchloric acid media, yielding selectively 1,3-di- and 1,3,5-trisubstituted tetrazolium salts. 1,3-Disubstituted salts are slowly converted under the same conditions into the corresponding 1,4-disubstituted salts. This transformation may be used for selective synthesis of the latter.