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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.

2

Comparative Studies on Tetrakis(mi0-1,3-benzothiazole-2-thiol-N,S)-dipalladium(II) with and with out Ethanol Solvent Molecule

Xiao X. L., Zhang K. J., Zhao P. S., Jian F. F.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 11

1929-1936

EN

The complex of dinuclear palladium(II), [Pd2(C7H4NS2)4]źC2H5OH, has been synthe - sized and characterized by elemental analysis, IR, UV-Vis spectra, X-ray single crystal diffraction and density functional theory (DFT) calculations. The structure of [Pd2(C7H4NS2)4]źC2H5OH consists of binuclear units of composition [Pd2(C7H4NS2)4] and an ethanol solvent molecule. The coordination geometry around Pd is square-planar, with two Pd atoms linked by four bridging 1,3-benzothiazole-2-thiol ligands via their exocyclic S and heterocyclic N atoms. The PdźźźPd distance is 2.738(2) capital A, ring. Density functional theory (DFT) calculations of the structure, total energy and electronic configu - ration have been carried out for the compound [Pd2(C7H4NS2)4]źC2H5OH and the com - pound [Pd2(C7H4NS2)4]. The calculated results indicate that the presence of sol vent C2H5OH has little influence on the molecule structure of [Pd2(C7H4NS2)4]. The solvent C2H5OH molecule changes the electronic configuration of the [Pd2(C7H4NS2)4].

3

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.

4

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.

5

Synthesis, Characterization and ab initio Calculations on 1-Phenyl-3-p-fluorophenyl-5-p-methoxyphenyl-2-pyrazoline

Zhao P. S., Li Y. F., Guo H. M., Wang X., Jian F. F.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 10

1735-1735

EN

1-Phenyl-3-p-fluorophenyl-5-p-methoxyphenyl-2-pyrazoline has been synthesized and characterized by elemental analysis, IR, UV-Vis and X-ray single crystal diffraction. Ab initio calculations for the title compound have been carried out and the calculated results show that HF/6-311G** method can well reproduce the structural parameters. The theoretical electronic absorption spectra have been predicted by using 6-311G** and 6-311++G** basis sets and compared with the experimental values, indicating that HF-CIS method can well predict electronic absorption spectra for the system studied here. On the basis of vibrational analyses, the thermodynamic properties of the title compound at different temperatures have been calculated, revealing the correlations between C 0 p,m , S 0 m , H 0 m and temperature.

6

Crystal Structure, Infrared Spectra and Density Functional Theory Study on 2,3-Diketo-benzopiperazine Dimer

Zhao P., Jian F. F., Xiao H., Sun P.

Polish Journal of Chemistry

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2004

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Vol. 78 / nr 10

1935-1944

EN

2,3-Diketo-benzopiperazine, which exists as dimeric form in its crystal structure has been synthesized. The calculated results on the dimer at B3LYP/6-31G* level show that the average strength of the double hydrogen bonds is of medium-grade. Natural bond orbital analyses have been performed. The predicted harmonic vibration frequencies support the experimental values. The thermodynamic properties of the dimer at different temperatures have been calculated and the change of Gibbs free energy for the aggregation from the monomer to the dimerDelta GT = -30.86 kJ/mol at 298.15 K, which implies the spontaneous process of the dimer formation.

7

N,N-Bispropyldithiocarbamato Bis(triphenylphosphine) Copper(I) Dichloromethane Solvate: [(n-Pr)2dtc(PPh3)2}Cu_CH2Cl2, (dtc=Dithiocarbamate)

Xu L., Lin J. H., Zhang S. S., Jiao K., Jian F. F.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 5

755-757