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2001 Volume 18 Issue 11
2001, 18(11): 853-856
Abstract:
Layered double oxide(LDO) immobilized penicillin G acylase(PGA) has been studied by XRD and TEM. The results show that the LDO, obtained by calcination at 500℃ of layered double hydroxides(LDH) having an ordered layered structure, has a disordered layered structure. PGA has an obvious effect on the LDO when the basity of LDO decreased, vice versa. The memory effect of LDO is due to transition of its disordered layered structure into ordered layered structure.
Layered double oxide(LDO) immobilized penicillin G acylase(PGA) has been studied by XRD and TEM. The results show that the LDO, obtained by calcination at 500℃ of layered double hydroxides(LDH) having an ordered layered structure, has a disordered layered structure. PGA has an obvious effect on the LDO when the basity of LDO decreased, vice versa. The memory effect of LDO is due to transition of its disordered layered structure into ordered layered structure.
2001, 18(11): 857-860
Abstract:
Three kinds of reactive toughening accelerators for epoxy resin/dicyandiamide system, amine-terminated chain-extended urea(TP), imidazole-terminated chain-extended urea(TI0) and 2-methylimidazole-terminated chain-extended urea (TI1) were synthesized from polyurethane prepolymer. Compared with the unmodified system, the curing activity, glass transition temperature, impact property and fracture surface morphology of the modified systems were investigated by DSC, SEM and measurement viscoelasticity. The results show that the curing activity was so greatly enhanced that the curing peak temperature decreased from 190℃ for the unmodified system to 120~140℃ for the modified systems, and the apparent activation energy of curing reaction decreased from 131 kJ/mol to 70~80 kJ/mol. Furthermore, the impact strength of the curing systems modified with TIn was 2~3 times as high as that of the unmodified system, while the glass transition temperature was little changed, and the fracture surface of the modified systems became tougher.
Three kinds of reactive toughening accelerators for epoxy resin/dicyandiamide system, amine-terminated chain-extended urea(TP), imidazole-terminated chain-extended urea(TI0) and 2-methylimidazole-terminated chain-extended urea (TI1) were synthesized from polyurethane prepolymer. Compared with the unmodified system, the curing activity, glass transition temperature, impact property and fracture surface morphology of the modified systems were investigated by DSC, SEM and measurement viscoelasticity. The results show that the curing activity was so greatly enhanced that the curing peak temperature decreased from 190℃ for the unmodified system to 120~140℃ for the modified systems, and the apparent activation energy of curing reaction decreased from 131 kJ/mol to 70~80 kJ/mol. Furthermore, the impact strength of the curing systems modified with TIn was 2~3 times as high as that of the unmodified system, while the glass transition temperature was little changed, and the fracture surface of the modified systems became tougher.
2001, 18(11): 861-864
Abstract:
The extraction of propionic acid in organic phase has been carried out by using trioctylamine(TOA) as an extractant, n-octanol as a diluent. By FTIR technique the fraction of the ion-pair extracted species(Ⅰ) and apparent equilibrium constant K11 were estimated. The results showed that the Ⅰ values obtained in this process depended on the association ability of ion-pair between propionic acid and TOA, concentration of TOA and solubility of the extracted species in organic phase.
The extraction of propionic acid in organic phase has been carried out by using trioctylamine(TOA) as an extractant, n-octanol as a diluent. By FTIR technique the fraction of the ion-pair extracted species(Ⅰ) and apparent equilibrium constant K11 were estimated. The results showed that the Ⅰ values obtained in this process depended on the association ability of ion-pair between propionic acid and TOA, concentration of TOA and solubility of the extracted species in organic phase.
2001, 18(11): 865-868
Abstract:
The grafting degree and shear viscosity under constant shear stress of PP-g-MAH as function of contents of MAH, dicumyl peroxide(DCP) and additives has been investigated. The mechanism of melt grafting of polypropylene(PP) with maleic anhydride(MAH) proposed previously by authors is proved to be correct through reactive extrusion. It is evident that decreasing the tendency of reaction between the peroxide radicals and the MAH monomer and enhancing the tendency of reaction between the macromolecular radicals and MAH will result in the formation of final product having higher grafting degree and higher molecular weight simultaneously.
The grafting degree and shear viscosity under constant shear stress of PP-g-MAH as function of contents of MAH, dicumyl peroxide(DCP) and additives has been investigated. The mechanism of melt grafting of polypropylene(PP) with maleic anhydride(MAH) proposed previously by authors is proved to be correct through reactive extrusion. It is evident that decreasing the tendency of reaction between the peroxide radicals and the MAH monomer and enhancing the tendency of reaction between the macromolecular radicals and MAH will result in the formation of final product having higher grafting degree and higher molecular weight simultaneously.
2001, 18(11): 869-872
Abstract:
Six new glycyrrhetic acid derivatives were synthesized from the reaction of di(2-chloroethyl)aminophosohonyl dichloride(4) with methyl glycyrrhetinate(1), methyl-11-deoxy glycyrrhetinate(2), and 3-U-30-dioxy-12-ene oleanane(3), respectively. Their structures were confirmed by MS, 1H NMR and elemental analysis. The preliminary antitumor activity tests against EAC cells both in vitro and in rovo showed that the new compounds especially Ⅰa and Ⅰb exhibited a good antifumor activity in comparison with the nitrogen mustard.
Six new glycyrrhetic acid derivatives were synthesized from the reaction of di(2-chloroethyl)aminophosohonyl dichloride(4) with methyl glycyrrhetinate(1), methyl-11-deoxy glycyrrhetinate(2), and 3-U-30-dioxy-12-ene oleanane(3), respectively. Their structures were confirmed by MS, 1H NMR and elemental analysis. The preliminary antitumor activity tests against EAC cells both in vitro and in rovo showed that the new compounds especially Ⅰa and Ⅰb exhibited a good antifumor activity in comparison with the nitrogen mustard.
2001, 18(11): 873-876
Abstract:
UV curable, hard, transparent hybrid coating material of epoxy acrylate resin was prepared by the sol-gel method, using Ⅴ-(trimethoxysilyl) propoxymethacrylate(TMSPM) as a coupling agent between the orgnic and inorganic phases. The FTIR, DSC studies, SEM observation and thermogravimetric analysis were used for the characterization. The physical properties of the hybrid materials showed that covalent links between the inorganic and organic networks may provide the hybrid with good flexibility and high hardness.
UV curable, hard, transparent hybrid coating material of epoxy acrylate resin was prepared by the sol-gel method, using Ⅴ-(trimethoxysilyl) propoxymethacrylate(TMSPM) as a coupling agent between the orgnic and inorganic phases. The FTIR, DSC studies, SEM observation and thermogravimetric analysis were used for the characterization. The physical properties of the hybrid materials showed that covalent links between the inorganic and organic networks may provide the hybrid with good flexibility and high hardness.
2001, 18(11): 877-880
Abstract:
Ten ferrocenyl-1,1'-dialkylferrocenylmethanols were prepared by reduction of corresponding ferrocenoyl-1,1'-dialkylferrocens with LiAlH4. The hydroxyl group containing compounds with ethyl groups in 1 and 1' positions of two ferrocenyls are very sensitive to acid, forming stable ferrocenyl-1,1'-dialkylferrocenylmethyl carbocations in CH2Cl2 in the presence of BF3. The cabocations thus obtained in reaction with CH3CH2NH2 gave the corresponding ethylamino compounds. All of the compounds synthesized were characterized by IR and 1H NMR spectrometric mesurements.
Ten ferrocenyl-1,1'-dialkylferrocenylmethanols were prepared by reduction of corresponding ferrocenoyl-1,1'-dialkylferrocens with LiAlH4. The hydroxyl group containing compounds with ethyl groups in 1 and 1' positions of two ferrocenyls are very sensitive to acid, forming stable ferrocenyl-1,1'-dialkylferrocenylmethyl carbocations in CH2Cl2 in the presence of BF3. The cabocations thus obtained in reaction with CH3CH2NH2 gave the corresponding ethylamino compounds. All of the compounds synthesized were characterized by IR and 1H NMR spectrometric mesurements.
2001, 18(11): 881-884
Abstract:
The synthesis of the immobilization carrier of polyphenol oxidase(PPO): polyvinyl alcohol grafted glutamic acid resin(PGAR) has been studied and the structure of the PGAR has been characterized by IR and DTA techniques. The results showed that the PPO was immobilized onto the carrier resin through coordination with Cu2+, forming PGAR-Cu-PPO. The optimum pH for immobilization was 5.59 and 6.64, and the Michaelis-Menten constant was of 1.70×10-2 mol/L, both are the same as those for free PPO. The immobilized PPO can be used repeatedly and the activity was found reduced by 80% after being reused 5 times.
The synthesis of the immobilization carrier of polyphenol oxidase(PPO): polyvinyl alcohol grafted glutamic acid resin(PGAR) has been studied and the structure of the PGAR has been characterized by IR and DTA techniques. The results showed that the PPO was immobilized onto the carrier resin through coordination with Cu2+, forming PGAR-Cu-PPO. The optimum pH for immobilization was 5.59 and 6.64, and the Michaelis-Menten constant was of 1.70×10-2 mol/L, both are the same as those for free PPO. The immobilized PPO can be used repeatedly and the activity was found reduced by 80% after being reused 5 times.
2001, 18(11): 885-888
Abstract:
Fe-P-O catalysts were prepared by both the coprecipitation and sol-gel methods. The compositions, structures and the chemisorption of ethane on the surface of Fe-P-O catalysts were investigated by DTA-TG, TEM, XRD, BET, IR and TPR techniques. The results showed that the Fe-P-O catalyst particle prepared by sol-gel method were non-crystal and well-distributed ultrafine particles of 10~20 nm. They gave a higher specific surface area and lattice oxygen activity than that of Fe-P-O catalyst prepared by the coprecipitation method. C2H6 could be adsorbed by P=O of the catalyst on its surface in a molecular adsorption state, and the adsorption ability and amount of C2H6 increased with temperature. Moreover, the adsorbed amount of ethane on non crystal state of FePO4 was greater than that on crystal state of FePO4.
Fe-P-O catalysts were prepared by both the coprecipitation and sol-gel methods. The compositions, structures and the chemisorption of ethane on the surface of Fe-P-O catalysts were investigated by DTA-TG, TEM, XRD, BET, IR and TPR techniques. The results showed that the Fe-P-O catalyst particle prepared by sol-gel method were non-crystal and well-distributed ultrafine particles of 10~20 nm. They gave a higher specific surface area and lattice oxygen activity than that of Fe-P-O catalyst prepared by the coprecipitation method. C2H6 could be adsorbed by P=O of the catalyst on its surface in a molecular adsorption state, and the adsorption ability and amount of C2H6 increased with temperature. Moreover, the adsorbed amount of ethane on non crystal state of FePO4 was greater than that on crystal state of FePO4.
2001, 18(11): 889-892
Abstract:
The temperature and atmosphere of heat treatment showed important effects on the carbon and hydrogen contents in final carbonized poly(p-phenylene) resin. The carbon contents of samples treated in an inert atmosphere were lower than those of samples treated in reductive atmosphere at the same temperatures; but hydrogen contents of samples were just the opposite to it. And the samples treated at 1 000℃ still contained hydrogen. The specific surface areas of samples treated at 1 000℃ in an inert atmosphere dropped to 15 6% as compared with those for the sample treated at 1 000℃ in reductive atmosphere. The specific surface areas of carbonized product decreased with increase in carbonization temperature. The IR and X-ray diffraction spectral analysis showed that the samples treated at 700℃ began to form fused benzene ring structure, but the carbons still belong to amorphous carbon. At 1 000℃ there appeared some graphite characteristic diffraction peaks in XRD spectra and higher graphitization level.
The temperature and atmosphere of heat treatment showed important effects on the carbon and hydrogen contents in final carbonized poly(p-phenylene) resin. The carbon contents of samples treated in an inert atmosphere were lower than those of samples treated in reductive atmosphere at the same temperatures; but hydrogen contents of samples were just the opposite to it. And the samples treated at 1 000℃ still contained hydrogen. The specific surface areas of samples treated at 1 000℃ in an inert atmosphere dropped to 15 6% as compared with those for the sample treated at 1 000℃ in reductive atmosphere. The specific surface areas of carbonized product decreased with increase in carbonization temperature. The IR and X-ray diffraction spectral analysis showed that the samples treated at 700℃ began to form fused benzene ring structure, but the carbons still belong to amorphous carbon. At 1 000℃ there appeared some graphite characteristic diffraction peaks in XRD spectra and higher graphitization level.
2001, 18(11): 893-897
Abstract:
The influences of concentrations of medium and passivator on film surface of copper and polishing process have been studied by electrochemical messurements as functions of polishing pressures, disk rates, film thickness and tightness in chemical mechanical polishing(CMP) process. Electrochemical variables, such as E-corrosion and I-corrosion explaining CMP processes and polishing rates were investigated. The following conclusions were obtained: 1)The concentrations of medium and passivator played a key role in passive film thickness and tightness on the surface of copper; 2)The polishing pressures and rotative rates depended on film thickness and tightness; 3)The removing and regenerating rates of the film influenced the CMP process.
The influences of concentrations of medium and passivator on film surface of copper and polishing process have been studied by electrochemical messurements as functions of polishing pressures, disk rates, film thickness and tightness in chemical mechanical polishing(CMP) process. Electrochemical variables, such as E-corrosion and I-corrosion explaining CMP processes and polishing rates were investigated. The following conclusions were obtained: 1)The concentrations of medium and passivator played a key role in passive film thickness and tightness on the surface of copper; 2)The polishing pressures and rotative rates depended on film thickness and tightness; 3)The removing and regenerating rates of the film influenced the CMP process.
2001, 18(11): 898-902
Abstract:
The platinum particles were electrodeposited on poly(2,5 dimethoxyaniline)(PDM An) membrane modified electrode. The polymer was obtained by emulsion polymerization. The surface configuration and crystal orientation of Pt particles have been investigated by SEM and XRD. The results of the oxidation of isopropanol on platinized PDM An modified electrode show that Pt particles deposited towards preferred-orientation on Pt(200), and, the increase in polymer electroactivity due to proton doping affects the dimension and graininess of deposited Pt particles. The metallized polymer modified electrode is proved to be a "microheterogeneous catalysis system". At the metallized polymer electrode the oxidation of isopropanol mainly took place on Pt particles, and the polymer not only plays a role as a dispersion medium but also affects the catalysis property of Pt particles.
The platinum particles were electrodeposited on poly(2,5 dimethoxyaniline)(PDM An) membrane modified electrode. The polymer was obtained by emulsion polymerization. The surface configuration and crystal orientation of Pt particles have been investigated by SEM and XRD. The results of the oxidation of isopropanol on platinized PDM An modified electrode show that Pt particles deposited towards preferred-orientation on Pt(200), and, the increase in polymer electroactivity due to proton doping affects the dimension and graininess of deposited Pt particles. The metallized polymer modified electrode is proved to be a "microheterogeneous catalysis system". At the metallized polymer electrode the oxidation of isopropanol mainly took place on Pt particles, and the polymer not only plays a role as a dispersion medium but also affects the catalysis property of Pt particles.
2001, 18(11): 903-907
Abstract:
The activity of Ni-Ce/γ-Al2O3 catalyst prepared by impregnation and coprecipitation was evaluated in a fixed bed continuous-flow quartz reactor. DTA-TGA, TPR, XRD and XPS have been used to characterize the catalysts. All the catalysts exhibited high conversion activity of CH4, indicating that methane can be activated by nickel species dispersed on the surface of catalysts. In the other hand, the freshly formed nickel species from NiAl2O4 pretreated and reduced at high temperature, is very active for CO2 conversion. Thus, the catalyst prepared by coprecipitation reveals higher CO2 conversion and CO yield than the catalyst prepared by impregnation.
The activity of Ni-Ce/γ-Al2O3 catalyst prepared by impregnation and coprecipitation was evaluated in a fixed bed continuous-flow quartz reactor. DTA-TGA, TPR, XRD and XPS have been used to characterize the catalysts. All the catalysts exhibited high conversion activity of CH4, indicating that methane can be activated by nickel species dispersed on the surface of catalysts. In the other hand, the freshly formed nickel species from NiAl2O4 pretreated and reduced at high temperature, is very active for CO2 conversion. Thus, the catalyst prepared by coprecipitation reveals higher CO2 conversion and CO yield than the catalyst prepared by impregnation.
2001, 18(11): 908-911
Abstract:
The reactions of methane decomposition to deposited carbon, CO2 reforming of methane to deposited carbon and CO2 elimination of carbon over hexaaluminate LaNiAl11O19 catalyst have been studied as a function of the appearance, sources, kinds and activities of deposited carbon by TEM, XPS, TGA, TPR-CO2 techniques. The results showed that methane exhibited rather high decomposition activity and carbide carbon and graphitic carbon were detected. However, the activity of CO2 decomposition to deposited carbon was lower, but its activity of eliminating carbon was higher.
The reactions of methane decomposition to deposited carbon, CO2 reforming of methane to deposited carbon and CO2 elimination of carbon over hexaaluminate LaNiAl11O19 catalyst have been studied as a function of the appearance, sources, kinds and activities of deposited carbon by TEM, XPS, TGA, TPR-CO2 techniques. The results showed that methane exhibited rather high decomposition activity and carbide carbon and graphitic carbon were detected. However, the activity of CO2 decomposition to deposited carbon was lower, but its activity of eliminating carbon was higher.
2001, 18(11): 912-914
Abstract:
The adsorption behavior and photocatalytic degradation of humic acid(HA) on nano-TiO2 particles in water have been studied under UV illumination as functions of pH and the concentration of TiO2. The results showed that the adsorption of HA on TiO2 particles was pH-dependent and pzc(point of zero charge of TiO2)-dependent due to electrostatic interaction. The adsorption behavior of HA on TiO2 particles played a very important role in the photocatalytic process. Increasing TiO2 concentration in a neutral medium enhanced the photodegradation.
The adsorption behavior and photocatalytic degradation of humic acid(HA) on nano-TiO2 particles in water have been studied under UV illumination as functions of pH and the concentration of TiO2. The results showed that the adsorption of HA on TiO2 particles was pH-dependent and pzc(point of zero charge of TiO2)-dependent due to electrostatic interaction. The adsorption behavior of HA on TiO2 particles played a very important role in the photocatalytic process. Increasing TiO2 concentration in a neutral medium enhanced the photodegradation.
2001, 18(11): 915-917
Abstract:
The self-assemble behavior of amphiphilic poly(styrene-b-acrylic acid), P(S-b-AA), in selective solvents was studied by dynamic light scattering(DLS). The diameters of micellae were found to be decreased and then increased with the increase in the concentration of the calcium ion in solvent. The average diameter of micellae was minimum when the concentration of the CaCl2 was 0.2 g/L. In addition, the distribution of micellae became narrow with the increase in the ethylenediamine concentration.
The self-assemble behavior of amphiphilic poly(styrene-b-acrylic acid), P(S-b-AA), in selective solvents was studied by dynamic light scattering(DLS). The diameters of micellae were found to be decreased and then increased with the increase in the concentration of the calcium ion in solvent. The average diameter of micellae was minimum when the concentration of the CaCl2 was 0.2 g/L. In addition, the distribution of micellae became narrow with the increase in the ethylenediamine concentration.
2001, 18(11): 918-920
Abstract:
The Cu/Cr base catalysts were prepared by impregnation. XRD and TPR technology were applied to characterize the catalysts. The result showed that the Cu/Cr base catalysts performed much better than the conventional Cu/Zn/Al catalysts. The stability of the catalysts was enhanced by promoters such as K, Mg, Ni, Y. But the promoters reduced the initial activity of the catalysts. The promoters except Y improved the selectivity apparently.
The Cu/Cr base catalysts were prepared by impregnation. XRD and TPR technology were applied to characterize the catalysts. The result showed that the Cu/Cr base catalysts performed much better than the conventional Cu/Zn/Al catalysts. The stability of the catalysts was enhanced by promoters such as K, Mg, Ni, Y. But the promoters reduced the initial activity of the catalysts. The promoters except Y improved the selectivity apparently.
2001, 18(11): 921-923
Abstract:
The flotation separation behavior of cobalt(Ⅱ) in ammonium thiocyanate-ethyl violet(EV)-H2O system and the conditions for the separation of cobalt(Ⅱ) from other metal ions have been inves-tigated. It showed that Co(Ⅱ) can be separated almost quantitatively from Ni(Ⅱ)、Fe(Ⅲ)、Mn(Ⅱ) and Al(Ⅲ) by adding 0.80 mL of 0.1 mol/L thiocyanate and 3.00 mL of 1×10-3 mol/L ethyl violet at pH=1.0~3.0.
The flotation separation behavior of cobalt(Ⅱ) in ammonium thiocyanate-ethyl violet(EV)-H2O system and the conditions for the separation of cobalt(Ⅱ) from other metal ions have been inves-tigated. It showed that Co(Ⅱ) can be separated almost quantitatively from Ni(Ⅱ)、Fe(Ⅲ)、Mn(Ⅱ) and Al(Ⅲ) by adding 0.80 mL of 0.1 mol/L thiocyanate and 3.00 mL of 1×10-3 mol/L ethyl violet at pH=1.0~3.0.
2001, 18(11): 924-926
Abstract:
Palladium-catalyzed ethoxycarbonylation reaction of arenediazonium tetrafluoroborates has been carried out under very mild conditions in the presence of a catalytic amount of Pd(OAc)2 and CaO to afford a variety of substituted ethyl benzoates in good yields. The effects of the catalyst and the base on ethoxycarbonylation reaction were investigated and CaO was shown to be the best base. The ethoxycarbonylation reaction can tolerate a variety of substituents in the benzene rings and has very high chemoselectivity. This paper provides a simple and practical procedure for syntheses of a variety of substituted ethyl benzoates.
Palladium-catalyzed ethoxycarbonylation reaction of arenediazonium tetrafluoroborates has been carried out under very mild conditions in the presence of a catalytic amount of Pd(OAc)2 and CaO to afford a variety of substituted ethyl benzoates in good yields. The effects of the catalyst and the base on ethoxycarbonylation reaction were investigated and CaO was shown to be the best base. The ethoxycarbonylation reaction can tolerate a variety of substituents in the benzene rings and has very high chemoselectivity. This paper provides a simple and practical procedure for syntheses of a variety of substituted ethyl benzoates.
2001, 18(11): 927-929
Abstract:
The power-time curves of the extraction oscillation reaction were determined at different temperatures for the extraction of hydrochloric acid and phosphoric acid by primary amine N1923 in chloroform, using a titration microcalorimetric method. The apparent activation energy were calculated from the induction period(tin), the first oscillation period(tp.1) and the second oscillation period(tp.2). The oscillation behavior were discussed.
The power-time curves of the extraction oscillation reaction were determined at different temperatures for the extraction of hydrochloric acid and phosphoric acid by primary amine N1923 in chloroform, using a titration microcalorimetric method. The apparent activation energy were calculated from the induction period(tin), the first oscillation period(tp.1) and the second oscillation period(tp.2). The oscillation behavior were discussed.
2001, 18(11): 930-932
Abstract:
The blends of HQ-PPEK, prepared by polymerization of 4-(4-hydroxyphenyl)-1-phthalazone(DHPZ) and hydroquinone(HQ)(1:1 molar ratio) with 4,4'-diflourodiphenylketone and polycarbonate(PC) through coprecipitation in chloroform solution. The miscibility of the blends was characterized by ternary-solution methods and DSC. The results indicated that the blends were immiscible or partially miscible. The rheological properties of the blends were studied by capillary rheometer. The results show that the melt blends are psedoplastic fluids, the die swelling ratios decrease and the non-Newtonian index increases with increase in the weight content of PC in the blends and the blends viscosity curves negatively does not follow the single additivity rule.
The blends of HQ-PPEK, prepared by polymerization of 4-(4-hydroxyphenyl)-1-phthalazone(DHPZ) and hydroquinone(HQ)(1:1 molar ratio) with 4,4'-diflourodiphenylketone and polycarbonate(PC) through coprecipitation in chloroform solution. The miscibility of the blends was characterized by ternary-solution methods and DSC. The results indicated that the blends were immiscible or partially miscible. The rheological properties of the blends were studied by capillary rheometer. The results show that the melt blends are psedoplastic fluids, the die swelling ratios decrease and the non-Newtonian index increases with increase in the weight content of PC in the blends and the blends viscosity curves negatively does not follow the single additivity rule.
2001, 18(11): 933-935
Abstract:
Five titanocene amino acid complexes, Cp2Ti(O2CCH2NHC6H4R)2 (R=H, p-Cl, p-OC2H5, m-CH3, m-Cl), have been prepared in a two-phase system(CHCl3/H2O), by reacting Cp2TiCl2 with corresponding amino acids (RC6H4NHCH2COOH). The complexes were characterized by elemental analysis, IR and 1H NMR spectra. The results show that the carboxyl oxygen is bound to Ti to form two-molecular amino acid complex and the carboxyl itself in amino acid acts as monodentate ligand. In comparison with synthesis in aqueous or anhydrolytic medium, the reaction in two-phase medium appears more simply and conveniently, with yield being higher.
Five titanocene amino acid complexes, Cp2Ti(O2CCH2NHC6H4R)2 (R=H, p-Cl, p-OC2H5, m-CH3, m-Cl), have been prepared in a two-phase system(CHCl3/H2O), by reacting Cp2TiCl2 with corresponding amino acids (RC6H4NHCH2COOH). The complexes were characterized by elemental analysis, IR and 1H NMR spectra. The results show that the carboxyl oxygen is bound to Ti to form two-molecular amino acid complex and the carboxyl itself in amino acid acts as monodentate ligand. In comparison with synthesis in aqueous or anhydrolytic medium, the reaction in two-phase medium appears more simply and conveniently, with yield being higher.
2001, 18(11): 936-938
Abstract:
Aminoguanidine was synthesized from aminoiminomethanesulfonic acid(AIMSO3H hydrate) and hydrazine hydrate in yield of 89% and purity of 86%. The product is characterized by IR, color reaction and molecular mass determination. Water is a good medium for synthesis. The optimum reaction temperature is 60℃. The reactant ratio showed an obvious on the yield.
Aminoguanidine was synthesized from aminoiminomethanesulfonic acid(AIMSO3H hydrate) and hydrazine hydrate in yield of 89% and purity of 86%. The product is characterized by IR, color reaction and molecular mass determination. Water is a good medium for synthesis. The optimum reaction temperature is 60℃. The reactant ratio showed an obvious on the yield.
