The non-isothermal degradation kinetics of N,N'-di(diethoxythiophosphoryl)-1,4-phenylenediamine in N2 was studied by TG-DTG techniques.The kinetic parameters,including the activation energy and pre-exponential fact...The non-isothermal degradation kinetics of N,N'-di(diethoxythiophosphoryl)-1,4-phenylenediamine in N2 was studied by TG-DTG techniques.The kinetic parameters,including the activation energy and pre-exponential factor of the degradation process for the title compound were calculated by means of the Kissinger and Flynn-Wall-Ozawa(FWO)method and the thermal degradation mechanism of the title compound was also studied with the Satava-Sestak methods.The results indicate that the activation energy and pre-exponential factor are 152.61 kJ/mol and 9.06×101 4s -1with the Kissinger method and 154.08 kJ/mol with the Flynn-Wall-Ozawa method,respectively.It has been shown that the degradation of the title compound follows a kinetic model of one-dimensional diffusion or parabolic law,the kinetic function is G(α)=α2and the reaction order is n=2.展开更多
A fast, high efficiency and environmentally friendly procedure for the synthesis of 2-aryl benzim-idazole derivatives has been reported. Reaction between 1,2-phenylenediamine derivatives and arylidene malononitrile un...A fast, high efficiency and environmentally friendly procedure for the synthesis of 2-aryl benzim-idazole derivatives has been reported. Reaction between 1,2-phenylenediamine derivatives and arylidene malononitrile under aqueous media and also solvent-free conditions generates 2-aryl benzimidazole derivatives with a high yield.展开更多
A reversed-phase high-performance liquid chromatographic method for the separation and quantitation of 1,4-phenylenediamine, 4-aminophenol, 3-aminophenol, 1,3-benzendiol and 2,6-phenylenediamine in hair dyes was devel...A reversed-phase high-performance liquid chromatographic method for the separation and quantitation of 1,4-phenylenediamine, 4-aminophenol, 3-aminophenol, 1,3-benzendiol and 2,6-phenylenediamine in hair dyes was developed. The separation was carried out on a mu-Bondapak C-18 column with methanol-water containing 0.1% triethylamine and 0.02 mol/L NH4Ac (pH=5.20) (10:90. vol./vol.) as the mobile phase. Two real samples were analyzed.展开更多
The synthesis of 5,15-bis[4-(methoxycarbonyl)phenyl]-10,20-diphenylporphyrin (2) and its reduction to 5,15- bis[4-(hydroxymethyl)phenyl]-10,20-diphenylporphyrin (3), and so its oxidation to provide 5,15-bis(4...The synthesis of 5,15-bis[4-(methoxycarbonyl)phenyl]-10,20-diphenylporphyrin (2) and its reduction to 5,15- bis[4-(hydroxymethyl)phenyl]-10,20-diphenylporphyrin (3), and so its oxidation to provide 5,15-bis(4-formylphenyl)-10,20- diphenylporphyrin (4) are reported. The copolymer possessing β-cyclodextrin (fl-CD), n-conjugated porphyrin and polyazomethine systems was synthesized by the polycondensation of porphyrin-dialdehyde monomer (4) and ,β- cyclodextrin/1,4-phenylenediamine complex (5). The monomers and the copolymer were characterized by UV-Vis, ^1H-NMR and IR spectra. Furthermore, ^1H-NMR and FT-IR spectra confirmed locating the aromatic ring of 1,4-phenylenediamine molecule in the center of β-cyclodextrin cavity.展开更多
Magnetically recoverable Fe3O4 nanoparticles have been synthesized as a catalyst for the cyclocondensation of 1,2-phenylenediamines with orthoesters under solvent-free conditions.Catalyst loadings can be as low as 1 m...Magnetically recoverable Fe3O4 nanoparticles have been synthesized as a catalyst for the cyclocondensation of 1,2-phenylenediamines with orthoesters under solvent-free conditions.Catalyst loadings can be as low as 1 mol% to give high yields of the corresponding benzimidazole derivative at 80 °C.This green method offers significant advantages in terms of its simplicity,low catalyst loadings,high product yields,and non-toxic nature.The Fe3O4 nanoparticles were characterized by X-ray diffraction,transmission electron microscopy,and Fourier transform infrared spectroscopy.展开更多
Silica gel-loaded (E)-N-(1-thien-2'-ylethylidene)-1,2-phenylenediamine (TEPDA) phase was synthesized based on physical adsorption approaches. The stability of a chemically modified TEPDA especially in concentra...Silica gel-loaded (E)-N-(1-thien-2'-ylethylidene)-1,2-phenylenediamine (TEPDA) phase was synthesized based on physical adsorption approaches. The stability of a chemically modified TEPDA especially in concentrated hydrochloric acid that was then used as a recycling and preconcentration reagent allowed the further uses of silica gel-loaded immobilized TEPDA phase. The application of this silica gel-loaded phase to sorption of a series of metal ions was performed by using different controlling factors such as the pH of the metal ion solution and the equilibration shaking time by the static technique. This difference was interpreted on the basis of selectivity incorporated in these sulfur containing silica gel-loaded TEPDA phases. Hg(Ⅱ) was found to exhibit the highest affinity towards extraction by these silica gel-loaded TEPDA phases. The pronounced selectivity was also confirmed by the determined distribution coefficients (Kd) of all the metal ions, showing the highest value reported for mercury(Ⅱ) extraction by the silica gel immobilized TEPDA phase. The potential applications of the silica gel immobilized TEPDA phase to selective extraction of mercury(Ⅱ) from aqueous solution were successfully accomplished and preconcentration of low concentration of Hg(Ⅱ) (30 pg·mL^-1) from natural tap water with a preconcentration factor of 200 for Hg(Ⅱ) off-line analysis was conducted by cold vapor atomic absorption analysis.展开更多
One-pot condensation of 2-aminothiophenol or 1,2-phenylenediamine with different aldehydes has been catalyzed by hexamethylenetetramine-bromine(HMTA-Bromine) as new,available and effective catalyst.2-Arylbenzo thiaz...One-pot condensation of 2-aminothiophenol or 1,2-phenylenediamine with different aldehydes has been catalyzed by hexamethylenetetramine-bromine(HMTA-Bromine) as new,available and effective catalyst.2-Arylbenzo thiazoles and 2-aryl benzimidazoles have been achieved in excellent yield and good purity.展开更多
基金the China Petroleum&Chemical Science and Technology Foundation(No.205026)the Tianjin Science andTechnology Plan Foundation,China(No.06TXTJJC14400).
文摘The non-isothermal degradation kinetics of N,N'-di(diethoxythiophosphoryl)-1,4-phenylenediamine in N2 was studied by TG-DTG techniques.The kinetic parameters,including the activation energy and pre-exponential factor of the degradation process for the title compound were calculated by means of the Kissinger and Flynn-Wall-Ozawa(FWO)method and the thermal degradation mechanism of the title compound was also studied with the Satava-Sestak methods.The results indicate that the activation energy and pre-exponential factor are 152.61 kJ/mol and 9.06×101 4s -1with the Kissinger method and 154.08 kJ/mol with the Flynn-Wall-Ozawa method,respectively.It has been shown that the degradation of the title compound follows a kinetic model of one-dimensional diffusion or parabolic law,the kinetic function is G(α)=α2and the reaction order is n=2.
文摘A fast, high efficiency and environmentally friendly procedure for the synthesis of 2-aryl benzim-idazole derivatives has been reported. Reaction between 1,2-phenylenediamine derivatives and arylidene malononitrile under aqueous media and also solvent-free conditions generates 2-aryl benzimidazole derivatives with a high yield.
文摘A reversed-phase high-performance liquid chromatographic method for the separation and quantitation of 1,4-phenylenediamine, 4-aminophenol, 3-aminophenol, 1,3-benzendiol and 2,6-phenylenediamine in hair dyes was developed. The separation was carried out on a mu-Bondapak C-18 column with methanol-water containing 0.1% triethylamine and 0.02 mol/L NH4Ac (pH=5.20) (10:90. vol./vol.) as the mobile phase. Two real samples were analyzed.
基金University of Kashan for supporting this work by Grant No. 159183/1
文摘The synthesis of 5,15-bis[4-(methoxycarbonyl)phenyl]-10,20-diphenylporphyrin (2) and its reduction to 5,15- bis[4-(hydroxymethyl)phenyl]-10,20-diphenylporphyrin (3), and so its oxidation to provide 5,15-bis(4-formylphenyl)-10,20- diphenylporphyrin (4) are reported. The copolymer possessing β-cyclodextrin (fl-CD), n-conjugated porphyrin and polyazomethine systems was synthesized by the polycondensation of porphyrin-dialdehyde monomer (4) and ,β- cyclodextrin/1,4-phenylenediamine complex (5). The monomers and the copolymer were characterized by UV-Vis, ^1H-NMR and IR spectra. Furthermore, ^1H-NMR and FT-IR spectra confirmed locating the aromatic ring of 1,4-phenylenediamine molecule in the center of β-cyclodextrin cavity.
基金support of this work by the Yasouj University,Iran
文摘Magnetically recoverable Fe3O4 nanoparticles have been synthesized as a catalyst for the cyclocondensation of 1,2-phenylenediamines with orthoesters under solvent-free conditions.Catalyst loadings can be as low as 1 mol% to give high yields of the corresponding benzimidazole derivative at 80 °C.This green method offers significant advantages in terms of its simplicity,low catalyst loadings,high product yields,and non-toxic nature.The Fe3O4 nanoparticles were characterized by X-ray diffraction,transmission electron microscopy,and Fourier transform infrared spectroscopy.
基金Project supported by the National Natural Science Foundation of China (No. 20271025), the Natural Science Foundation of Shandong Province (No. L2003B01) and the State Key Laboratory of Crystal Materials, Shandong University.
文摘Silica gel-loaded (E)-N-(1-thien-2'-ylethylidene)-1,2-phenylenediamine (TEPDA) phase was synthesized based on physical adsorption approaches. The stability of a chemically modified TEPDA especially in concentrated hydrochloric acid that was then used as a recycling and preconcentration reagent allowed the further uses of silica gel-loaded immobilized TEPDA phase. The application of this silica gel-loaded phase to sorption of a series of metal ions was performed by using different controlling factors such as the pH of the metal ion solution and the equilibration shaking time by the static technique. This difference was interpreted on the basis of selectivity incorporated in these sulfur containing silica gel-loaded TEPDA phases. Hg(Ⅱ) was found to exhibit the highest affinity towards extraction by these silica gel-loaded TEPDA phases. The pronounced selectivity was also confirmed by the determined distribution coefficients (Kd) of all the metal ions, showing the highest value reported for mercury(Ⅱ) extraction by the silica gel immobilized TEPDA phase. The potential applications of the silica gel immobilized TEPDA phase to selective extraction of mercury(Ⅱ) from aqueous solution were successfully accomplished and preconcentration of low concentration of Hg(Ⅱ) (30 pg·mL^-1) from natural tap water with a preconcentration factor of 200 for Hg(Ⅱ) off-line analysis was conducted by cold vapor atomic absorption analysis.
文摘One-pot condensation of 2-aminothiophenol or 1,2-phenylenediamine with different aldehydes has been catalyzed by hexamethylenetetramine-bromine(HMTA-Bromine) as new,available and effective catalyst.2-Arylbenzo thiazoles and 2-aryl benzimidazoles have been achieved in excellent yield and good purity.