Login In
1996 Volume 7 Issue 7
1996, 7(7): 597-599
Abstract:
Synthesis of three new tetrathiafulvalene (TTF) derivatives-tetrakis (p-halobenzylthio)-tetrathiafulvalene and their precursors 4, 5-bis (p-halobenzylthio)-1, 3-dithiole-2-thione is reported. The electronic absorption spectra of these TTF derivatives show that the energy differences between their π-orbitals are smaller than that between BEDT-TTF. The surface pressure-area isotherm for tetrakis (p-chlorobenzylthio) tetrathiafulvalene (TCBT-TTF) indicates that the new TTF derivatives may have good film-forming properties and may be used to prepare Langmuir-Blodgett films.
Synthesis of three new tetrathiafulvalene (TTF) derivatives-tetrakis (p-halobenzylthio)-tetrathiafulvalene and their precursors 4, 5-bis (p-halobenzylthio)-1, 3-dithiole-2-thione is reported. The electronic absorption spectra of these TTF derivatives show that the energy differences between their π-orbitals are smaller than that between BEDT-TTF. The surface pressure-area isotherm for tetrakis (p-chlorobenzylthio) tetrathiafulvalene (TCBT-TTF) indicates that the new TTF derivatives may have good film-forming properties and may be used to prepare Langmuir-Blodgett films.
1996, 7(7): 600-602
Abstract:
A series of new diaryl 2-nitro-1, 4-phenylenedioxydiacetates were synthesized by the reaction of 2-nitro-1, 4-phenylenedioxydiacetyl chloride with various substituted phenols under the condition of liquid-liquid phase transfer catalysis using polyethylene glycol-400 as the catalyst.
A series of new diaryl 2-nitro-1, 4-phenylenedioxydiacetates were synthesized by the reaction of 2-nitro-1, 4-phenylenedioxydiacetyl chloride with various substituted phenols under the condition of liquid-liquid phase transfer catalysis using polyethylene glycol-400 as the catalyst.
1996, 7(7): 603-604
Abstract:
Protodesilylation of (2H)-pyridazinon-5-yl silylmethyl sulfides 1 proceeds smoothly with cleavage of sp3 hybridized carbon-silicon bond in the presence of catalytic amount of sodium hydroxide at room temperature. The presence of aryl R on silicon atom and (2H)-pyridazinon-5-yl group on sulfur atom plays a critical role in the occurrence of this reaction.
Protodesilylation of (2H)-pyridazinon-5-yl silylmethyl sulfides 1 proceeds smoothly with cleavage of sp3 hybridized carbon-silicon bond in the presence of catalytic amount of sodium hydroxide at room temperature. The presence of aryl R on silicon atom and (2H)-pyridazinon-5-yl group on sulfur atom plays a critical role in the occurrence of this reaction.
1996, 7(7): 605-608
Abstract:
A series of copoly (ester imide)s is synthesized by thermal polycondensation of N, N'-hexane-1, 6-diylbis (trimellitimide), p-hydroxybenzoic acid and diphenols with different structures. Their thermotropic liquid crystal properties are studied by DSC measurements and polarizing microscopy. It is found that the steric effect of nonlinear bisphenol modifiers is the most important factor in controlling the liquid crystallinity of the resulting copoly (ester imide)s.
A series of copoly (ester imide)s is synthesized by thermal polycondensation of N, N'-hexane-1, 6-diylbis (trimellitimide), p-hydroxybenzoic acid and diphenols with different structures. Their thermotropic liquid crystal properties are studied by DSC measurements and polarizing microscopy. It is found that the steric effect of nonlinear bisphenol modifiers is the most important factor in controlling the liquid crystallinity of the resulting copoly (ester imide)s.
1996, 7(7): 609-610
Abstract:
A series of succinimido-organophosphate analogues was synthesized with maleic anhydride as starting material via maleimide and its analogues as intermediates and characterized by IR, 1HNMR and elementary analysis.
A series of succinimido-organophosphate analogues was synthesized with maleic anhydride as starting material via maleimide and its analogues as intermediates and characterized by IR, 1HNMR and elementary analysis.
1996, 7(7): 611-614
Abstract:
A enzymatic synthesis of sugar ester from isopropylidenesugar and ω-3 polyunsaturated fatty acid was studied. Esterification with Lipase N-435 gave the best result.
A enzymatic synthesis of sugar ester from isopropylidenesugar and ω-3 polyunsaturated fatty acid was studied. Esterification with Lipase N-435 gave the best result.
1996, 7(7): 615-616
Abstract:
In Tris-HCl buffer, an intermolecular phosphoryl group transfer from N-(O, O-diisopropyl) phosphoryl asparagine (DIPPAsn) to trypsin was confirmed. The result suggested an novel way to phosphoiylate the protein without kinase participation.
In Tris-HCl buffer, an intermolecular phosphoryl group transfer from N-(O, O-diisopropyl) phosphoryl asparagine (DIPPAsn) to trypsin was confirmed. The result suggested an novel way to phosphoiylate the protein without kinase participation.
1996, 7(7): 617-618
Abstract:
A new styryl-lactone compound, named as leiocarpin A (1), was isolated from Goniothalamus leiocarpus. Its structure and relative configuration were determined by means of spectrum particularly 2D NMR including 1H-1H COSY, 1H-13C HETCOR, COLOC and NOESY techniques.
A new styryl-lactone compound, named as leiocarpin A (1), was isolated from Goniothalamus leiocarpus. Its structure and relative configuration were determined by means of spectrum particularly 2D NMR including 1H-1H COSY, 1H-13C HETCOR, COLOC and NOESY techniques.
1996, 7(7): 619-620
Abstract:
A new neo-clerodane type diterpenoid, named soulidiol, has been isolated from Aster souliei and its structure was elucidated on basis of spectral and chemical methods to be 18, 19-dihydroxy-5α, 10β-neo-cleroda-3, 13 (14)-dien-16, 15-olide.
A new neo-clerodane type diterpenoid, named soulidiol, has been isolated from Aster souliei and its structure was elucidated on basis of spectral and chemical methods to be 18, 19-dihydroxy-5α, 10β-neo-cleroda-3, 13 (14)-dien-16, 15-olide.
1996, 7(7): 621-622
Abstract:
A new rearranged abietane diterpenoid, incanone was isolated from the whole plant of Caryopteris incana (Thunb. ) Miq. On the basis of HRMS, EIMS, 1HNMR, 13CNMR, DEPT, 1H-1H COSY, HMQC, HMBC and NOESY, incanone was determined as 11, 12, 14, 16-tetrahydroxyl-17 (15-16) abeo-abieta-8, 11, 13-triene-7-one.
A new rearranged abietane diterpenoid, incanone was isolated from the whole plant of Caryopteris incana (Thunb. ) Miq. On the basis of HRMS, EIMS, 1HNMR, 13CNMR, DEPT, 1H-1H COSY, HMQC, HMBC and NOESY, incanone was determined as 11, 12, 14, 16-tetrahydroxyl-17 (15-16) abeo-abieta-8, 11, 13-triene-7-one.
1996, 7(7): 623-626
Abstract:
Cyclic voltammetry method was used to determine the cyclic voltammogram of artemisinin derivatives and reduction potentials (RPs) of these compounds were obtained. Combining the determination results of Zhang and co-workers, QSAR analysis was performed between the activity and reduction potentials (RPs), which illustrated the antimalarial mechanism of artemisinin analogs. The experimental result verified and tested our previous theoretical calculation results.
Cyclic voltammetry method was used to determine the cyclic voltammogram of artemisinin derivatives and reduction potentials (RPs) of these compounds were obtained. Combining the determination results of Zhang and co-workers, QSAR analysis was performed between the activity and reduction potentials (RPs), which illustrated the antimalarial mechanism of artemisinin analogs. The experimental result verified and tested our previous theoretical calculation results.
1996, 7(7): 627-630
Abstract:
A method to analyze the relationship between the helical structure and optical activity was proposed by the study of the conformations and X-ray structures of some cyclic esters possessing a C2-symmetry element which were prepared by esterification of L-(+)-2, 3-O-isopropylidene threitol with dicarboxylic dichlorides.
A method to analyze the relationship between the helical structure and optical activity was proposed by the study of the conformations and X-ray structures of some cyclic esters possessing a C2-symmetry element which were prepared by esterification of L-(+)-2, 3-O-isopropylidene threitol with dicarboxylic dichlorides.
1996, 7(7): 631-634
Abstract:
The reactions of vinyl fluoride, chloride, bromide and iodide with CN- and OH- were studied. The trend of reactivity of vinyl halide with these two nucleophile is:fluoroethene- tends to be a multi-step process while the reactions of the other three vinyl halides with CN-. OH- are all single-step processes. The nucleophilicity of CN- is stronger than that of OH-.
The reactions of vinyl fluoride, chloride, bromide and iodide with CN- and OH- were studied. The trend of reactivity of vinyl halide with these two nucleophile is:fluoroethene
1996, 7(7): 635-637
Abstract:
The coaggregating tendencies of dodecane, octadecane, dodecanol, octadecanol, dodecanoic acid, octadecanoic acid, methyl dodecanoate, methyl octadecanoate have been investigated by the fluorescence method, in 40:60 V/V (φ=0.40) DX-H2O system at 25℃. using naphthylene lauryl ether (Np-12) as fluorescence probe. These long chain molecules with different terminal groups have different coaggregating tendencies. The order is alkane >methyl ester of fatty acid >fatty alcohol >fatty acid. The unusual properties of carboxyl as terminal-group have been discussed.
The coaggregating tendencies of dodecane, octadecane, dodecanol, octadecanol, dodecanoic acid, octadecanoic acid, methyl dodecanoate, methyl octadecanoate have been investigated by the fluorescence method, in 40:60 V/V (φ=0.40) DX-H2O system at 25℃. using naphthylene lauryl ether (Np-12) as fluorescence probe. These long chain molecules with different terminal groups have different coaggregating tendencies. The order is alkane >methyl ester of fatty acid >fatty alcohol >fatty acid. The unusual properties of carboxyl as terminal-group have been discussed.
1996, 7(7): 638-640
Abstract:
The thermodynamic and kinetic information concerning reaction of FO with H2O are calculated using the general statistical theory and the transition state theory. The influence of temperature on this system is discussed. The view that FO is inactive to H2O in the atmosphere is confirmed. We also provide a standard program to study elemental reactions.
The thermodynamic and kinetic information concerning reaction of FO with H2O are calculated using the general statistical theory and the transition state theory. The influence of temperature on this system is discussed. The view that FO is inactive to H2O in the atmosphere is confirmed. We also provide a standard program to study elemental reactions.
1996, 7(7): 641-642
Abstract:
Trans-2-styrylbenzoxazole (Ⅰ) was included by host compound 1, 1, 6, 6-tetraphenylhexa-2, 4-diyn-1, 6-diol (Ⅱ) and the inclusion ratio was 1:1. Syn-head-to-tail dimer (Ⅳ) of Ⅰ was obtained by irradiating the inclusion complex (Ⅲ) with 400W High Pressure Mercury Lamp (HPML). The possible mechanism of the reaction was also discussed.
Trans-2-styrylbenzoxazole (Ⅰ) was included by host compound 1, 1, 6, 6-tetraphenylhexa-2, 4-diyn-1, 6-diol (Ⅱ) and the inclusion ratio was 1:1. Syn-head-to-tail dimer (Ⅳ) of Ⅰ was obtained by irradiating the inclusion complex (Ⅲ) with 400W High Pressure Mercury Lamp (HPML). The possible mechanism of the reaction was also discussed.
1996, 7(7): 643-646
Abstract:
The mechanism of the electrochemical reduction of the nickel (Ⅱ) complex with dimethylglyoxime and ammonia is studied by means of INDO, energy localization and electrostatic potential methods.
The mechanism of the electrochemical reduction of the nickel (Ⅱ) complex with dimethylglyoxime and ammonia is studied by means of INDO, energy localization and electrostatic potential methods.
1996, 7(7): 647-650
Abstract:
We have developed a new theoretical model based on the MPB4 theory to calculate the differential capacitance of the interface of 0.05mol/L MgSO4 in water and 0.1mol/L TBATPB in nitrobenzene. Our results coincide with the experimental values very well. It indicates that our model may describe well the structure of ITIES not only in the presence of 1:1 electrolyte but also in the presence of 2:2 electrolyte.
We have developed a new theoretical model based on the MPB4 theory to calculate the differential capacitance of the interface of 0.05mol/L MgSO4 in water and 0.1mol/L TBATPB in nitrobenzene. Our results coincide with the experimental values very well. It indicates that our model may describe well the structure of ITIES not only in the presence of 1:1 electrolyte but also in the presence of 2:2 electrolyte.
1996, 7(7): 651-652
Abstract:
Artificial neural network (ANN) models have been employed to the calculations of densities and excess molar volumes of water+methanol+ethylene glycol ternary system at different temperatures. The results were satisfactory comparing with the experimental values. The method was convenient in operation, rapid in calculation and easy in extending to multicomponent systems.
Artificial neural network (ANN) models have been employed to the calculations of densities and excess molar volumes of water+methanol+ethylene glycol ternary system at different temperatures. The results were satisfactory comparing with the experimental values. The method was convenient in operation, rapid in calculation and easy in extending to multicomponent systems.
1996, 7(7): 653-656
Abstract:
A new amorphous comblike polymer (CBP) based on methylvinyl ether/maleic anhydride alternating copolymer backbone and on oligooxyethylene side chain was synthesized. The dynamic mechanical properties of CBP-Li salt complexes showed that there were two glass transitions. There are two peaks in the plot of the ionic conductivity vs. Li salt concentration. The plot of Log σ against 1/(T-To) shows an unusual dual VTF behavior when using side chain glass transition temperature (Tβ) as To.
A new amorphous comblike polymer (CBP) based on methylvinyl ether/maleic anhydride alternating copolymer backbone and on oligooxyethylene side chain was synthesized. The dynamic mechanical properties of CBP-Li salt complexes showed that there were two glass transitions. There are two peaks in the plot of the ionic conductivity vs. Li salt concentration. The plot of Log σ against 1/(T-To) shows an unusual dual VTF behavior when using side chain glass transition temperature (Tβ) as To.
1996, 7(7): 657-660
Abstract:
The uptake kinetics of platinum (Ⅱ) complexes of 1, 2-diaminocyclohexane (dach) isomers (1R, 2R-dach, 1R, 2S-dach, 1S, 2S-dach) with various leaving groups, chloride (Cl), oxalate (OX), squaric acid (SA), and demethylcantharic acid (DA) was studied in the plasma isotonic buffer. The experimental results show that across-membrane transport of all the platinum complexes studied follows a firstorder kinetic process and a passive diffusion mechanism. The uptake rate constants of these platinum (Ⅱ) complexes decrease in the following sequence with the k value (h-1) :Cl >SA >OX >DA. It is noteworthy that the k values of the platinum (Ⅱ) complexes with same leaving group reduce as:1R, 2R-dach >1R, 2S-dach >1S, 2S-dach. Based on these results, it is firstly suggested that the erythrocyte membrane recognizes the chirality of these platinum complexes.
The uptake kinetics of platinum (Ⅱ) complexes of 1, 2-diaminocyclohexane (dach) isomers (1R, 2R-dach, 1R, 2S-dach, 1S, 2S-dach) with various leaving groups, chloride (Cl), oxalate (OX), squaric acid (SA), and demethylcantharic acid (DA) was studied in the plasma isotonic buffer. The experimental results show that across-membrane transport of all the platinum complexes studied follows a firstorder kinetic process and a passive diffusion mechanism. The uptake rate constants of these platinum (Ⅱ) complexes decrease in the following sequence with the k value (h-1) :Cl >SA >OX >DA. It is noteworthy that the k values of the platinum (Ⅱ) complexes with same leaving group reduce as:1R, 2R-dach >1R, 2S-dach >1S, 2S-dach. Based on these results, it is firstly suggested that the erythrocyte membrane recognizes the chirality of these platinum complexes.
1996, 7(7): 661-662
Abstract:
The adsorption and decomposition of cyclohexanone and phenol on Pt (Ⅲ) have been investigated by HREELS and TDS. The configuration of both adsorbates and the decomposition mechanisms are also discussed.
The adsorption and decomposition of cyclohexanone and phenol on Pt (Ⅲ) have been investigated by HREELS and TDS. The configuration of both adsorbates and the decomposition mechanisms are also discussed.
1996, 7(7): 663-664
Abstract:
Hydrogenation of nitroaromatics has been carried out under mild conditions using poly-N-vinyl-2-pyrrolidone supported Pd-Pt bimetallic catalysts (PdCl2 and H2PtCl6 as catalyst precursors). The catalytic activities of the bimetallic catalysts are significantly higher than those of the monometallic Pd or Pt catalyst especially in the case of the hydrogenation of substituted nitroaromatics due to a remarkable synergic effect. The ratio of Pd to Pt in the catalyst influences the activity of the catalyst.
Hydrogenation of nitroaromatics has been carried out under mild conditions using poly-N-vinyl-2-pyrrolidone supported Pd-Pt bimetallic catalysts (PdCl2 and H2PtCl6 as catalyst precursors). The catalytic activities of the bimetallic catalysts are significantly higher than those of the monometallic Pd or Pt catalyst especially in the case of the hydrogenation of substituted nitroaromatics due to a remarkable synergic effect. The ratio of Pd to Pt in the catalyst influences the activity of the catalyst.
1996, 7(7): 665-668
Abstract:
In order to investigate the relation between molecular structure and liquid crystal properties, structural studies were carried out on three-dimensional mesogen tetrasubstituted tribenzosilatrane using PM3 semiempirical calculations. The results show that the corresponding terminal cyano group compound (alkyl R2 replaced by CN) has much bigger dipole moment and much better similar to sphere than alkyl compounds. Cyano compound is probably a better candidate for sphere-like mesogen.
In order to investigate the relation between molecular structure and liquid crystal properties, structural studies were carried out on three-dimensional mesogen tetrasubstituted tribenzosilatrane using PM3 semiempirical calculations. The results show that the corresponding terminal cyano group compound (alkyl R2 replaced by CN) has much bigger dipole moment and much better similar to sphere than alkyl compounds. Cyano compound is probably a better candidate for sphere-like mesogen.
1996, 7(7): 669-670
Abstract:
The crystal structure of poly (ether ketone ketone)(PEKK) is predicted by using Cerius2 software according to the wide angle X-ray diffraction (WAXD) experiment result. The predicted structure has a planar zigzag chain conformation between ether oxygen and ketone carbons in an orthorhombic lattice. Average zigzag angle is 126° and average torsion angle is 30.32°, The WAXD powder pattern calculated from the crystal packing model is in good agreement with the experiment result.
The crystal structure of poly (ether ketone ketone)(PEKK) is predicted by using Cerius2 software according to the wide angle X-ray diffraction (WAXD) experiment result. The predicted structure has a planar zigzag chain conformation between ether oxygen and ketone carbons in an orthorhombic lattice. Average zigzag angle is 126° and average torsion angle is 30.32°, The WAXD powder pattern calculated from the crystal packing model is in good agreement with the experiment result.
1996, 7(7): 671-674
Abstract:
Dispersion of KF on AlPO4-5 molecular sieve created basic sites and caused 1654 cm-1band of bidentate carbonate in CO2 adsorption. After pre-treated above 823K, 5%KF/AlPO4-5 exhibited basic catalytic activity in the isomerization of butenes at 273K, and the activity increased with the pre-treatment temperature up to 923K.
Dispersion of KF on AlPO4-5 molecular sieve created basic sites and caused 1654 cm-1band of bidentate carbonate in CO2 adsorption. After pre-treated above 823K, 5%KF/AlPO4-5 exhibited basic catalytic activity in the isomerization of butenes at 273K, and the activity increased with the pre-treatment temperature up to 923K.
1996, 7(7): 675-678
Abstract:
Utilizing the effect of dioxygen molecules on the luminophors' phosphorescent life, the first attempt to investigate the interaction between the molecules of rare earth coordination compound and cells was carried out. This work has supplied a new research method for the studies of transmembrane process for rare earth ions.
Utilizing the effect of dioxygen molecules on the luminophors' phosphorescent life, the first attempt to investigate the interaction between the molecules of rare earth coordination compound and cells was carried out. This work has supplied a new research method for the studies of transmembrane process for rare earth ions.
1996, 7(7): 679-680
Abstract:
Chromium atom-hexane solution prepared in a metal atom reactor was transferred into a solution containing polystyrene in diethylene glycol dibutyl ether at -78℃, followed by gently warming the mixture to 0℃ to react for two hours, yielding a brown-green solid product. Ultraviolet-visible and infrared spectra showed that the product was a bi-(η6-arene) chromium complex.
Chromium atom-hexane solution prepared in a metal atom reactor was transferred into a solution containing polystyrene in diethylene glycol dibutyl ether at -78℃, followed by gently warming the mixture to 0℃ to react for two hours, yielding a brown-green solid product. Ultraviolet-visible and infrared spectra showed that the product was a bi-(η6-arene) chromium complex.
1996, 7(7): 681-684
Abstract:
Four new μ-oxamido heterobinuclear complexes of CuⅡ-LnⅢ (Ln:Y, Pr, Ho, Gd) were synthesized and characterized. The magnetic susceptibility measurements (4~300 K) of the CuⅡ-GdⅢ complex indicate a weak ferromagnetic interaction between the two metal ions, with the exchange integral JCu-Gd=2.03 cm-1.
Four new μ-oxamido heterobinuclear complexes of CuⅡ-LnⅢ (Ln:Y, Pr, Ho, Gd) were synthesized and characterized. The magnetic susceptibility measurements (4~300 K) of the CuⅡ-GdⅢ complex indicate a weak ferromagnetic interaction between the two metal ions, with the exchange integral JCu-Gd=2.03 cm-1.
1996, 7(7): 685-686
Abstract:
The magnetic susceptibility of[Bu4N][Ni (MEDT)2]and[BU4N] [Ni (PHDT) 2] (MEDT:5-methyl-6-hydro-1, 4-dithiin-2, 3-dithiolate, PHDT:5-phenyl-6-hydro-1, 4-dithiin-2, 3-dithiolate) was measured in the temperature range of 75-300K. The magnitude of magnetic moments is consistent with a doublet state arising from Ni (Ⅲ). Antiferromagnetic properties were discussed in consideration of molecular structure.
The magnetic susceptibility of[Bu4N][Ni (MEDT)2]and[BU4N] [Ni (PHDT) 2] (MEDT:5-methyl-6-hydro-1, 4-dithiin-2, 3-dithiolate, PHDT:5-phenyl-6-hydro-1, 4-dithiin-2, 3-dithiolate) was measured in the temperature range of 75-300K. The magnitude of magnetic moments is consistent with a doublet state arising from Ni (Ⅲ). Antiferromagnetic properties were discussed in consideration of molecular structure.
1996, 7(7): 687-690
Abstract:
A new type of silver sol was prepared by a method similar to physical development in photographic science. Silver particles have many crystalline forms with bigger size than that of usual silver sols. Kinetic study indicates that the reaction is an autocatalytic reaction. The result can also explain the particle size effect on the color of silver particles deposited by physical development in photographic science.
A new type of silver sol was prepared by a method similar to physical development in photographic science. Silver particles have many crystalline forms with bigger size than that of usual silver sols. Kinetic study indicates that the reaction is an autocatalytic reaction. The result can also explain the particle size effect on the color of silver particles deposited by physical development in photographic science.
