Login In
2002 Volume 19 Issue 5
2002, 19(5): 409-415
Abstract:
Sodium borohydride and its modified compounds are important reductants capable of reducing a great number of organic functional groups. Their extraordinary uses have been found in recent years. Much more developments have been reported concerning sodium borohydride and its modified derivatives as a reductant in reducing aldehydes, ketones, alcohols, esters, amides, nitriles, nitro compounds, imines, alkenes, alkynes, indoles and other compounds, which are briefly reviewed in this article.
Sodium borohydride and its modified compounds are important reductants capable of reducing a great number of organic functional groups. Their extraordinary uses have been found in recent years. Much more developments have been reported concerning sodium borohydride and its modified derivatives as a reductant in reducing aldehydes, ketones, alcohols, esters, amides, nitriles, nitro compounds, imines, alkenes, alkynes, indoles and other compounds, which are briefly reviewed in this article.
2002, 19(5): 416-419
Abstract:
Fourteen N-(4'-substituted pyrimidin-'-yl)-2-substituted phenoxysulfonylureas were synthesized and their structures were confirmed by 1H NMR and MS. The inference of substituents to chemical shift were discussed, and cleavage pathway of MS were analyzed. The compounds 1e、1f、1k、1m and 1n showed good herbicidal activity.
Fourteen N-(4'-substituted pyrimidin-'-yl)-2-substituted phenoxysulfonylureas were synthesized and their structures were confirmed by 1H NMR and MS. The inference of substituents to chemical shift were discussed, and cleavage pathway of MS were analyzed. The compounds 1e、1f、1k、1m and 1n showed good herbicidal activity.
2002, 19(5): 420-424
Abstract:
The atom-triples of some 1-[(2-hydroxyethoxy)methyl]-6-(phenylthio) thymine(HEPT) derivatives containing abundant three dimensional information of molecules were calculated. Molecular similarity matrix was built based on the frequency distributions of the atom-triples. These similarities being taken as the new variables were selected by using Leaps-and-Bounds regression analysis. Multiple regression analysis and neural networks were performed for building the prediction models, and the satisfactory results were obtained by using the neural networks.>The atom triples of some 1-[(2-hydroxyethoxy)methyl]-6-(phenylthio) thymine(HEPT) derivatives containing abundant three dimensional information of molecules were calculated. Molecular similarity matrix was built based on the frequency distributions of the atom triples. These similarities being taken as the new variables were selected by using Leaps and Bounds regression analysis. Multiple regression analysis and neural networks were performed for building the prediction models, and the satisfactory results were obtained by using the neural networks.
The atom-triples of some 1-[(2-hydroxyethoxy)methyl]-6-(phenylthio) thymine(HEPT) derivatives containing abundant three dimensional information of molecules were calculated. Molecular similarity matrix was built based on the frequency distributions of the atom-triples. These similarities being taken as the new variables were selected by using Leaps-and-Bounds regression analysis. Multiple regression analysis and neural networks were performed for building the prediction models, and the satisfactory results were obtained by using the neural networks.>The atom triples of some 1-[(2-hydroxyethoxy)methyl]-6-(phenylthio) thymine(HEPT) derivatives containing abundant three dimensional information of molecules were calculated. Molecular similarity matrix was built based on the frequency distributions of the atom triples. These similarities being taken as the new variables were selected by using Leaps and Bounds regression analysis. Multiple regression analysis and neural networks were performed for building the prediction models, and the satisfactory results were obtained by using the neural networks.
2002, 19(5): 425-427
Abstract:
The extraction behavior of metal ions including Eu3+, Zn2+, Cd2+, Co2+, Ni2+, Cu2+, Mn2+, Mg2+ from hydrochloric acid solutions have been investigated using a novel extractant, sec-nonylphenoxy acetic acid(HA), in n-heptane. The effects of equilibrium acidity in aqueous phase and extractant concentration on extraction equilibrium have been studied in detail and the extraction equations have been deduced based on slope analysis of lg D vs pH and lg D-n pH vs lg. At suitable pH values, Eu3+ can be effectively separated from Cu2+, Co2+, Ni2+, Zn2+, Cd2+, Mn2+ and Mg2+, Co2+ from Ni2+, and Zn2+ from Cd2+.
The extraction behavior of metal ions including Eu3+, Zn2+, Cd2+, Co2+, Ni2+, Cu2+, Mn2+, Mg2+ from hydrochloric acid solutions have been investigated using a novel extractant, sec-nonylphenoxy acetic acid(HA), in n-heptane. The effects of equilibrium acidity in aqueous phase and extractant concentration on extraction equilibrium have been studied in detail and the extraction equations have been deduced based on slope analysis of lg D vs pH and lg D-n pH vs lg. At suitable pH values, Eu3+ can be effectively separated from Cu2+, Co2+, Ni2+, Zn2+, Cd2+, Mn2+ and Mg2+, Co2+ from Ni2+, and Zn2+ from Cd2+.
2002, 19(5): 428-432
Abstract:
Partially reduced V-MnO2 were prepared from I.C.No1 EMD by stirring method and additional ultrasonic irradiation in aqueous or organic medium in the presence of hydrazine hydrate respectively. The reduced samples were characterized by oxidation degree analysis, XRD, IR and TEM. The results showed that in aqueous medium ultrasound can accelerate the reduction and change the crystal form of products. The main crystal form of product prepared under stirring condition was T-MnOOH and that with ultrasound promotion was V-MnOOH. The properties of electrode fabricated by these partially reduced MnOx were improved. The discharge capacity of partially reduced products increased by 21.5% compared with that of IC1.
Partially reduced V-MnO2 were prepared from I.C.No1 EMD by stirring method and additional ultrasonic irradiation in aqueous or organic medium in the presence of hydrazine hydrate respectively. The reduced samples were characterized by oxidation degree analysis, XRD, IR and TEM. The results showed that in aqueous medium ultrasound can accelerate the reduction and change the crystal form of products. The main crystal form of product prepared under stirring condition was T-MnOOH and that with ultrasound promotion was V-MnOOH. The properties of electrode fabricated by these partially reduced MnOx were improved. The discharge capacity of partially reduced products increased by 21.5% compared with that of IC1.
2002, 19(5): 433-436
Abstract:
The adsorption configuration and molecular motion behavior of sodium polyacrylate(Na-PA) on the surface of MgCO3 have been investigated by using the electron spin resonance(ESR) combined with spin labeling technique. The adsorption isotherm of sodium polyacrylate on the MgCO3 surface was of Langmuir type. The fraction of segments in trains(p) of the adsorbed Na-PA in the case of low surface coverage was greater and mainly in flattened shape, whereas in high surface coverage, the p value was relatively small and mainly in more loop shape. At the beginning of adsorption there occurs an attraction between the positive charges of MgCO3 surface and polyanions of PA causing the adsorption.
The adsorption configuration and molecular motion behavior of sodium polyacrylate(Na-PA) on the surface of MgCO3 have been investigated by using the electron spin resonance(ESR) combined with spin labeling technique. The adsorption isotherm of sodium polyacrylate on the MgCO3 surface was of Langmuir type. The fraction of segments in trains(p) of the adsorbed Na-PA in the case of low surface coverage was greater and mainly in flattened shape, whereas in high surface coverage, the p value was relatively small and mainly in more loop shape. At the beginning of adsorption there occurs an attraction between the positive charges of MgCO3 surface and polyanions of PA causing the adsorption.
2002, 19(5): 437-440
Abstract:
Poly(hexamethylene carbonate-co-sebacic anhydride)s(PHCSA) containing aliphatic polycarbonate and labile anhydride groups was synthesized by copolymerization of diacid derived from oligo(hexamethylene carbonate)diol(OHCMD) with sebacic acid(SA) in mass ratios of 25:75, 50:50 and 75:25. The structure of PHCSA was confirmed by FTIR and 1H NMR. The in vitro degradation of PHCSA was performed in 0.1 mol/L phosphate-buffer saline(PBS, pH 7-4) at 37℃. It was found that the degradation rate of PHCSA increased with the content of SA. After one-week degradation, the mass loss of PHCSA contained 80%, 58% and 32%(mole fraction) SA were 64.3%, 45.2% and 21.5% respectively. It was also found that the degradation of PHCSA could be catalyzed by lipase. After one week degradation in 1% lipase/PBS(0.1 mol/L, pH 7.4) at 37℃, the mass loss of PHCSA contained 58% and 32%(mole fraction) SA were 51.2% and 26.1% respectively. There was an obvious difference between the inner and the outer layer of samples in degradation. After two-week degradation, the Mw/Mw0 (ratio of final molecular weight to the initial molecular weight) of the inner layer and the outer layer of PHCSA contained 80%, 58% and 32%(mole fraction) SA were 89.9% and 27.9%, 98.1% and 39.1%, 97.8% and 47.2% respectively.
Poly(hexamethylene carbonate-co-sebacic anhydride)s(PHCSA) containing aliphatic polycarbonate and labile anhydride groups was synthesized by copolymerization of diacid derived from oligo(hexamethylene carbonate)diol(OHCMD) with sebacic acid(SA) in mass ratios of 25:75, 50:50 and 75:25. The structure of PHCSA was confirmed by FTIR and 1H NMR. The in vitro degradation of PHCSA was performed in 0.1 mol/L phosphate-buffer saline(PBS, pH 7-4) at 37℃. It was found that the degradation rate of PHCSA increased with the content of SA. After one-week degradation, the mass loss of PHCSA contained 80%, 58% and 32%(mole fraction) SA were 64.3%, 45.2% and 21.5% respectively. It was also found that the degradation of PHCSA could be catalyzed by lipase. After one week degradation in 1% lipase/PBS(0.1 mol/L, pH 7.4) at 37℃, the mass loss of PHCSA contained 58% and 32%(mole fraction) SA were 51.2% and 26.1% respectively. There was an obvious difference between the inner and the outer layer of samples in degradation. After two-week degradation, the Mw/Mw0 (ratio of final molecular weight to the initial molecular weight) of the inner layer and the outer layer of PHCSA contained 80%, 58% and 32%(mole fraction) SA were 89.9% and 27.9%, 98.1% and 39.1%, 97.8% and 47.2% respectively.
2002, 19(5): 441-445
Abstract:
The cyclic voltammetric(CV) behavior of silver oxide electrodes were investigated as function of scan rate and mass ratio of common Ag2O(d=0.5 μm) and nano Ag2O. The peak shapes in CV diagramms were differed for the three electrodes when the scan rate was 0.5 mV/s and their peak current values were obviously different at any scan rate. The optimum mixture electrode(sample A) exhibited remarkable cyclic reversibility, while the pure nanophase Ag2O electrode(sample F) was wear in receiving charges. The common Ag2O electrode(sample C) was just in between them. The best electrochemical property of the optimum mixture electrode could be due to the effectively reasonable distribution of the electroactive substances on the surface of electrode.
The cyclic voltammetric(CV) behavior of silver oxide electrodes were investigated as function of scan rate and mass ratio of common Ag2O(d=0.5 μm) and nano Ag2O. The peak shapes in CV diagramms were differed for the three electrodes when the scan rate was 0.5 mV/s and their peak current values were obviously different at any scan rate. The optimum mixture electrode(sample A) exhibited remarkable cyclic reversibility, while the pure nanophase Ag2O electrode(sample F) was wear in receiving charges. The common Ag2O electrode(sample C) was just in between them. The best electrochemical property of the optimum mixture electrode could be due to the effectively reasonable distribution of the electroactive substances on the surface of electrode.
2002, 19(5): 446-449
Abstract:
A series of thermal stable phase-transfer catalysts based on alkyl pyridium salt were synthesized, their catalytic activities were evaluated in the typical aromatic nucleophilic substitution reaction(fluorination). Among the catalysts prepared 4-(N',N'-dimethylamino)-N-ethylhexyl pyridinium salt(Cat 2) exhibited the highest catalytic activity. It give p-nitrofluorobene in yield up to 98.6% in 1.5 h reaction.
A series of thermal stable phase-transfer catalysts based on alkyl pyridium salt were synthesized, their catalytic activities were evaluated in the typical aromatic nucleophilic substitution reaction(fluorination). Among the catalysts prepared 4-(N',N'-dimethylamino)-N-ethylhexyl pyridinium salt(Cat 2) exhibited the highest catalytic activity. It give p-nitrofluorobene in yield up to 98.6% in 1.5 h reaction.
2002, 19(5): 450-454
Abstract:
The clear and transparent sols of BaTi acetate were prepared from tetrabutyltitanate, barium acetate aqueous solution, ethanol and acetic acid. The BaTi acetate sols were transferred into gels by sol-gel process, and the gels were dried and calcined to nanostructured BaTiO3 powders. The sol-gel transition process has been investigated as functions of initial pH value of sol, time and temperature of gel for the tetrabutyltitanate-barium acetate-acetic acid system. The rheological behavior occurred in the sol-gel transition have been investigated. It is found that the initial pH value of the sol affected not only the sol-gel transition, but also the particle size of the final calcined BaTiO3 powders. For the BaTi acetate sols with initial pH values of 3.8 and 5.3, the time from sol to gel was 40 and 120 h at 20℃, respectively; after dried at 80℃ and calcined at 700℃, the grain size of BaTiO3 powders was 90 and 70 nm, respectively.
The clear and transparent sols of BaTi acetate were prepared from tetrabutyltitanate, barium acetate aqueous solution, ethanol and acetic acid. The BaTi acetate sols were transferred into gels by sol-gel process, and the gels were dried and calcined to nanostructured BaTiO3 powders. The sol-gel transition process has been investigated as functions of initial pH value of sol, time and temperature of gel for the tetrabutyltitanate-barium acetate-acetic acid system. The rheological behavior occurred in the sol-gel transition have been investigated. It is found that the initial pH value of the sol affected not only the sol-gel transition, but also the particle size of the final calcined BaTiO3 powders. For the BaTi acetate sols with initial pH values of 3.8 and 5.3, the time from sol to gel was 40 and 120 h at 20℃, respectively; after dried at 80℃ and calcined at 700℃, the grain size of BaTiO3 powders was 90 and 70 nm, respectively.
2002, 19(5): 455-458
Abstract:
A superabsorbent resistant to saline solution was prepared from copolymer of sodium acrylate with sodium polymannuronate. The effects of the amount of sodium polymannuronate and initiator, degree of neutralization of acrylic acid, mole ratio of KOH to Na2CO3 on water absorbency(WA) and the hydrogel modulus of the copolymer were investigated. The results showed that WA of the superabsorbent was about 1 000 and 85 times its own mass respectively, if the superabsorbent was allowed to swell in distilled water and 0.9%(mass fraction) aqueous NaCl at room temperature for 30 min. The superabsorbent also had excellent hydrogel modulus.
A superabsorbent resistant to saline solution was prepared from copolymer of sodium acrylate with sodium polymannuronate. The effects of the amount of sodium polymannuronate and initiator, degree of neutralization of acrylic acid, mole ratio of KOH to Na2CO3 on water absorbency(WA) and the hydrogel modulus of the copolymer were investigated. The results showed that WA of the superabsorbent was about 1 000 and 85 times its own mass respectively, if the superabsorbent was allowed to swell in distilled water and 0.9%(mass fraction) aqueous NaCl at room temperature for 30 min. The superabsorbent also had excellent hydrogel modulus.
2002, 19(5): 459-463
Abstract:
Cu(Ⅱ)-Co(Ⅱ) heterobinuclear complex was synthesized from an oxalamide bridged macrocyclic dioxotetraamines and characterized by IR, UV-visible spectra, molar conductivity, thermogravity analysis, cyclic voltammetry and room temperature magetic moment measurements. The results suggested the Cu(Ⅱ)-Co(Ⅱ) heterobinuclear complex has an oxalamide brideged structure with copper(Ⅱ) being in a planar and cobalt(Ⅱ) in an octahedral environment. Room temperature magetic studies showed that there are weak antiferromagetic interactions between the two metal ions within a molecule. Cyclic voltammetry studies showed this complex can stabilize higher oxidation states of Cu(Ⅲ). Mononuclear Cu(Ⅱ) complex is of monoclinic system, space group P21/c, a=0.7386 1(15) nm, b=2.121 1(4) nm, c=0.952 50(19) nm, U=94.70(3)° and Z=4. Fall-matrix least-squares refinement of the structure led to a conventional weighted R factor of 0.051 3.
Cu(Ⅱ)-Co(Ⅱ) heterobinuclear complex was synthesized from an oxalamide bridged macrocyclic dioxotetraamines and characterized by IR, UV-visible spectra, molar conductivity, thermogravity analysis, cyclic voltammetry and room temperature magetic moment measurements. The results suggested the Cu(Ⅱ)-Co(Ⅱ) heterobinuclear complex has an oxalamide brideged structure with copper(Ⅱ) being in a planar and cobalt(Ⅱ) in an octahedral environment. Room temperature magetic studies showed that there are weak antiferromagetic interactions between the two metal ions within a molecule. Cyclic voltammetry studies showed this complex can stabilize higher oxidation states of Cu(Ⅲ). Mononuclear Cu(Ⅱ) complex is of monoclinic system, space group P21/c, a=0.7386 1(15) nm, b=2.121 1(4) nm, c=0.952 50(19) nm, U=94.70(3)° and Z=4. Fall-matrix least-squares refinement of the structure led to a conventional weighted R factor of 0.051 3.
2002, 19(5): 464-467
Abstract:
The extraction separation of Fe(Ⅲ) from crude Al2(SO4)3 solution with extractant P538 has been investigated. The results indicated that the high class product of Al2(SO4)3 could be obtained after a three stage extraction and stripping extractant from 0.5 mol/L H2SO4 solution.
The extraction separation of Fe(Ⅲ) from crude Al2(SO4)3 solution with extractant P538 has been investigated. The results indicated that the high class product of Al2(SO4)3 could be obtained after a three stage extraction and stripping extractant from 0.5 mol/L H2SO4 solution.
2002, 19(5): 468-470
Abstract:
The nano-sized U-Ni(OH)2 powder was synthesized and mixed with different amount of Al(OH)3 and Ni powders to fabricate electrodes. The electrodes propared exhibit increased activity, stable discharging potential, increased capacity with open circuit potential up to 2 5 V. The electrode after 5 hours charging under constant current of 3.0×10-3 A/cm2 could be discharged at 0.7×10-3 A/cm2 for period of 16 hours.
The nano-sized U-Ni(OH)2 powder was synthesized and mixed with different amount of Al(OH)3 and Ni powders to fabricate electrodes. The electrodes propared exhibit increased activity, stable discharging potential, increased capacity with open circuit potential up to 2 5 V. The electrode after 5 hours charging under constant current of 3.0×10-3 A/cm2 could be discharged at 0.7×10-3 A/cm2 for period of 16 hours.
2002, 19(5): 471-473
Abstract:
24-Methylenecholestan-3U,5T,6U-triol 1 isolated from the soft coral, Sinularia dissecia has high antifouling property and biodecomposability in natural environment, safe for human bodies. We have synthesized compound 1 in seven steps starting from stigmasterol 2 in overall yield of 31.3%. The side chain of stigmasterol 2 was modified to keto-containing structure of compound 3 via hydroxy group and olefin protection, ozonization, wittig reaction and hydrogenation. The A/B ring was modified by oxidation with performic acid to give stereospecific 5T,6U-diol sterol 4. The compound 1 was then obtained by methylenation of cabonyl group at the 24C of 4 through Wittig reaction in a rather strict conditions. The mp, [T] and NMR data of synthesized 1 were in good agreement with that of the natural compound reported by Masaru[4]. This is the first time of the synthesis of 24-methylenecholest 3U,5T,6U-triol 1.
24-Methylenecholestan-3U,5T,6U-triol 1 isolated from the soft coral, Sinularia dissecia has high antifouling property and biodecomposability in natural environment, safe for human bodies. We have synthesized compound 1 in seven steps starting from stigmasterol 2 in overall yield of 31.3%. The side chain of stigmasterol 2 was modified to keto-containing structure of compound 3 via hydroxy group and olefin protection, ozonization, wittig reaction and hydrogenation. The A/B ring was modified by oxidation with performic acid to give stereospecific 5T,6U-diol sterol 4. The compound 1 was then obtained by methylenation of cabonyl group at the 24C of 4 through Wittig reaction in a rather strict conditions. The mp, [T] and NMR data of synthesized 1 were in good agreement with that of the natural compound reported by Masaru[4]. This is the first time of the synthesis of 24-methylenecholest 3U,5T,6U-triol 1.
2002, 19(5): 474-476
Abstract:
The light-absorption characteristics of the bacteriorhodopsin(BR) have been studied as function of relationship between absorbance and mass concentration of BR suspension, pH and temperature of BR suspension. It was found that the absorbance is linearly related to the mass concentration of BR suspension. When pH increased from 5 to 8, BR was stable; when pH was greater than 8 or lower than 5, the following functional relation between pH and absorbance can be obtained, respectively:(33.19-86.21A)0.5=pH-7.80, (57.33-133.3A)0.5=7.09-pH. No obvious variation of absorbance of BR suspension was observed at temperature from 0 to 30℃, but absorbance was found to be decreased markedly at temperature higher than 30℃. The pH of BR suspension increased with the temperature.
The light-absorption characteristics of the bacteriorhodopsin(BR) have been studied as function of relationship between absorbance and mass concentration of BR suspension, pH and temperature of BR suspension. It was found that the absorbance is linearly related to the mass concentration of BR suspension. When pH increased from 5 to 8, BR was stable; when pH was greater than 8 or lower than 5, the following functional relation between pH and absorbance can be obtained, respectively:(33.19-86.21A)0.5=pH-7.80, (57.33-133.3A)0.5=7.09-pH. No obvious variation of absorbance of BR suspension was observed at temperature from 0 to 30℃, but absorbance was found to be decreased markedly at temperature higher than 30℃. The pH of BR suspension increased with the temperature.
2002, 19(5): 477-479
Abstract:
The activities of Cu/Mn/Mg/K catalyst with different supporter have been investigated in methanol decomposition reaction as function of copper-support interaction, dispersion and valency structure of copper and pore structure of catalysts. XRD, TPR, XPS and BET methods are used to characterize the structure of catalysts and interaction between CuO/Cu and support. The results indicated that the Cu/Mn/Mg/K catalyst is much better than conventional Cu/Zn/Al catalyst in methanol decomposition, the supporters behave differently, and the catalyst supported on Al2O3 gives the best result.
The activities of Cu/Mn/Mg/K catalyst with different supporter have been investigated in methanol decomposition reaction as function of copper-support interaction, dispersion and valency structure of copper and pore structure of catalysts. XRD, TPR, XPS and BET methods are used to characterize the structure of catalysts and interaction between CuO/Cu and support. The results indicated that the Cu/Mn/Mg/K catalyst is much better than conventional Cu/Zn/Al catalyst in methanol decomposition, the supporters behave differently, and the catalyst supported on Al2O3 gives the best result.
2002, 19(5): 480-482
Abstract:
The in-situ synthesized detonating explosive(EIS) was separated and purified by certain solvents. The structure and composition of EIS were investigated by chemical analysis, infrared spectroscopy, X-ray diffraction analysis and mass spectroscopy. The mechanism of the synthesis was briefly discussed.
The in-situ synthesized detonating explosive(EIS) was separated and purified by certain solvents. The structure and composition of EIS were investigated by chemical analysis, infrared spectroscopy, X-ray diffraction analysis and mass spectroscopy. The mechanism of the synthesis was briefly discussed.
2002, 19(5): 483-485
Abstract:
The Bi2O3 was prepared from Bi(NO3)3·5H2O, followed by calcination of its alkali salt. The Bi2O3 was used as photocatalyst in photocatalytic decoloration of dyes. The results showed that the Bi2O3 exhibited a better photocatalytic activity under illumination of sunlight than that illuminated by Hg-lamp.
The Bi2O3 was prepared from Bi(NO3)3·5H2O, followed by calcination of its alkali salt. The Bi2O3 was used as photocatalyst in photocatalytic decoloration of dyes. The results showed that the Bi2O3 exhibited a better photocatalytic activity under illumination of sunlight than that illuminated by Hg-lamp.
2002, 19(5): 486-488
Abstract:
DM-130 macro-porous adsorptive resin was used to extract flavonoid glycosides from leaching solution and some factors affecting the adsorption efficiency were examined. The optimum technological conditions as follows:pH=5, mass ratio of liquid to solid 15 in adsorption and 70% ethanol as eluting agent. Resin could be regenerated after every three time uses. The content of flavonoids glycosides in extracts was about 24%.
DM-130 macro-porous adsorptive resin was used to extract flavonoid glycosides from leaching solution and some factors affecting the adsorption efficiency were examined. The optimum technological conditions as follows:pH=5, mass ratio of liquid to solid 15 in adsorption and 70% ethanol as eluting agent. Resin could be regenerated after every three time uses. The content of flavonoids glycosides in extracts was about 24%.
2002, 19(5): 489-490
Abstract:
sym-Diphenylethane was prepared by reductive coupling reaction in water using iron powder as catalyst and Cu2Cl2 as cocatalyst. The product was characterized by infrared analysis, H-NMR analysis and melting point measurement. The effects of catalyst molar ratio and reaction temperature were examined. The results showed that on the condition of n(benzyl chloride):n(Fe):n(Cu2Cl2)=1.8:1:0.02, at 90℃, 86.7% yield could be achieved.
sym-Diphenylethane was prepared by reductive coupling reaction in water using iron powder as catalyst and Cu2Cl2 as cocatalyst. The product was characterized by infrared analysis, H-NMR analysis and melting point measurement. The effects of catalyst molar ratio and reaction temperature were examined. The results showed that on the condition of n(benzyl chloride):n(Fe):n(Cu2Cl2)=1.8:1:0.02, at 90℃, 86.7% yield could be achieved.
2002, 19(5): 491-493
Abstract:
A new compound was synthesized with 1,2,3-trimethoxybenzene as the starting material, followed by acylation of Friedel Crafts, bromination reaction, the nucleophilic N-substitution of imidazole. For 2-bromo-1-(2,3,4-trimethoxyphenyl)ethanone in DMF,2-(1H-imidazol-1-yl)-1-(2,3,4-trimethoxyphenyl) ethanone was obtained in yield of 62.7%. It was obtained that the best reaction condition which the molar ratio of bromo compound to imidazole will be 1:5 and the reaction time will be 8 h under low temperature or room temperature. The structure of the product was confirmed by elemental analysis, 1H NMR and IR spectrum analysis.
A new compound was synthesized with 1,2,3-trimethoxybenzene as the starting material, followed by acylation of Friedel Crafts, bromination reaction, the nucleophilic N-substitution of imidazole. For 2-bromo-1-(2,3,4-trimethoxyphenyl)ethanone in DMF,2-(1H-imidazol-1-yl)-1-(2,3,4-trimethoxyphenyl) ethanone was obtained in yield of 62.7%. It was obtained that the best reaction condition which the molar ratio of bromo compound to imidazole will be 1:5 and the reaction time will be 8 h under low temperature or room temperature. The structure of the product was confirmed by elemental analysis, 1H NMR and IR spectrum analysis.
2002, 19(5): 494-496
Abstract:
TiO2/glass film photocatalysts have been prepared by a sol-gel method with titanium tetrabutoxide as precursor, and used in photocatalytic degradation of 2,4-dichlorophenol(DCP) in aqueous solution. The experiments indicated that the TiO2/glass film coated with five layers of TiO2 sol in the case of higher pH value(≥10) or lower pH value(≤2) showed a higher catalytic activity, and the relationship between initial DCP concentration(c0) and reaction rate(r0) follows Langmuir Hinshelwood equation. The photocatalytic degradation kinetics of DCP(c0≤0.5 mmol/L) is of first order kinetics.
TiO2/glass film photocatalysts have been prepared by a sol-gel method with titanium tetrabutoxide as precursor, and used in photocatalytic degradation of 2,4-dichlorophenol(DCP) in aqueous solution. The experiments indicated that the TiO2/glass film coated with five layers of TiO2 sol in the case of higher pH value(≥10) or lower pH value(≤2) showed a higher catalytic activity, and the relationship between initial DCP concentration(c0) and reaction rate(r0) follows Langmuir Hinshelwood equation. The photocatalytic degradation kinetics of DCP(c0≤0.5 mmol/L) is of first order kinetics.
2002, 19(5): 497-498
Abstract:
Five nopyl ethers and two nopyl esters have been synthesized, and their 13C NMR spectra have been recorded. The C-6, C-7 chemical shifts in their 13C NMR spectra have been discussed in terms of configuration structure. It is suggested that the C-1, C-2, C-3, C-4 and C-5 atoms are in the same plan and the 6,6-dimethylbicyclo[3.1.1]hept-2-ene part is in the Y-shape. The ethers and esters obtained appeared to be derivatives of apopinene 6,6 dimethylbicyclo[3.1.1]hept-2-ene with substituents at the C-2 position. The effect of substituents occured mainly on the chemical shifts of C-1, C-2 and C-3. There seemes a weaker steric interaction of the substituents with other carbon atoms.
Five nopyl ethers and two nopyl esters have been synthesized, and their 13C NMR spectra have been recorded. The C-6, C-7 chemical shifts in their 13C NMR spectra have been discussed in terms of configuration structure. It is suggested that the C-1, C-2, C-3, C-4 and C-5 atoms are in the same plan and the 6,6-dimethylbicyclo[3.1.1]hept-2-ene part is in the Y-shape. The ethers and esters obtained appeared to be derivatives of apopinene 6,6 dimethylbicyclo[3.1.1]hept-2-ene with substituents at the C-2 position. The effect of substituents occured mainly on the chemical shifts of C-1, C-2 and C-3. There seemes a weaker steric interaction of the substituents with other carbon atoms.
2002, 19(5): 499-500
Abstract:
Seven 5-arylidenebarbituric acids were synthesized by a solid phase condensation reaction of aromatic aldehyde with barbituric acid in the presence of ammonium acetate. The reactions could be completed in 5~8 min with 65%~93% yields.
Seven 5-arylidenebarbituric acids were synthesized by a solid phase condensation reaction of aromatic aldehyde with barbituric acid in the presence of ammonium acetate. The reactions could be completed in 5~8 min with 65%~93% yields.
2002, 19(5): 501-502
Abstract:
The trimer complex was synthesized by reacting MnCl2 with 2,2'-bipyridine-1,1'-dioxide(bipyO2) in DMF. The elemental analysis, IR, UV and molar conductivity results indicated the composition of the complex was[Mn3(bipyO2)4Cl4]Cl2.The complex dissolves in water, but does not in organic solvents such as C2H5OH, C2H5OC2H5, CHCl3, CH3COCH3, C7H8, DMF and THF. The complex exhibited good sensitivity and selectivity to ammonia of high concentration. It could be used to detect and control NH3 in the concentration range of 1.0×10-4~5.0×10-4 mol/L.
The trimer complex was synthesized by reacting MnCl2 with 2,2'-bipyridine-1,1'-dioxide(bipyO2) in DMF. The elemental analysis, IR, UV and molar conductivity results indicated the composition of the complex was[Mn3(bipyO2)4Cl4]Cl2.The complex dissolves in water, but does not in organic solvents such as C2H5OH, C2H5OC2H5, CHCl3, CH3COCH3, C7H8, DMF and THF. The complex exhibited good sensitivity and selectivity to ammonia of high concentration. It could be used to detect and control NH3 in the concentration range of 1.0×10-4~5.0×10-4 mol/L.
2002, 19(5): 503-505
Abstract:
The N,N'-bis(o-hydroxy-p-methoxybezophenone)-ethylenediamine complexes with copper(Ⅱ) 、nickel(Ⅱ) and cobalt(Ⅱ)[MC30H26N2O4] were synthesized by solid-liquid phase reaction. The complexes were characterized by elemental analysis, XRD, UV, IR and 1H NMR. The crystal structure of the complexes belongs to triclinic system with the cell parameters: a=1.297 1 nm, b=1.621 0 nm, c=2.047 0 nm, T=85.40°,U=88.80°, V=99.00° for[CuC30H26N2O4·0.5H2O]; a=1.300 2 nm, b=1.882 6 nm, c=2.127 4 nm, T=86.47°,U=89.23°, V=99.11° for[NiC30H26N2O4]; a=1.286 5 nm, b=1.596 1 nm, c=2.056 9 nm, T=87.95°, U=93.17°, V=98.21° for[CoC30H26N2O4], respectively. The N and O atoms in the complexes appeared coordinated directly to the metal ions. A quadridentate chelate may be formed.
The N,N'-bis(o-hydroxy-p-methoxybezophenone)-ethylenediamine complexes with copper(Ⅱ) 、nickel(Ⅱ) and cobalt(Ⅱ)[MC30H26N2O4] were synthesized by solid-liquid phase reaction. The complexes were characterized by elemental analysis, XRD, UV, IR and 1H NMR. The crystal structure of the complexes belongs to triclinic system with the cell parameters: a=1.297 1 nm, b=1.621 0 nm, c=2.047 0 nm, T=85.40°,U=88.80°, V=99.00° for[CuC30H26N2O4·0.5H2O]; a=1.300 2 nm, b=1.882 6 nm, c=2.127 4 nm, T=86.47°,U=89.23°, V=99.11° for[NiC30H26N2O4]; a=1.286 5 nm, b=1.596 1 nm, c=2.056 9 nm, T=87.95°, U=93.17°, V=98.21° for[CoC30H26N2O4], respectively. The N and O atoms in the complexes appeared coordinated directly to the metal ions. A quadridentate chelate may be formed.
2002, 19(5): 506-508
Abstract:
The chemical reduction and electro-reduction behavior of perfluorodecalin have been investigated under the illumination of UV light. The IR spectra of the resulting products showed that the same functional group, acyl fluoride, could be formed in both reduction processes. The results of 19F NMR and UV-vis spectra revealed that there were other different functional groups formed in the two reduction processes. In the electro chemical reduction, conjunctive double bonds could be formed in the same and different carbon ring. In the chemical reduction, using Zn and Mg as reducing agents, aromatic structure was formed in the products.
The chemical reduction and electro-reduction behavior of perfluorodecalin have been investigated under the illumination of UV light. The IR spectra of the resulting products showed that the same functional group, acyl fluoride, could be formed in both reduction processes. The results of 19F NMR and UV-vis spectra revealed that there were other different functional groups formed in the two reduction processes. In the electro chemical reduction, conjunctive double bonds could be formed in the same and different carbon ring. In the chemical reduction, using Zn and Mg as reducing agents, aromatic structure was formed in the products.
2002, 19(5): 509-510
Abstract:
U-Naphthyl acetate was synthesized in yield of 96.8% using sodium bisulfate as catalyst. The optimum conditions were as follows: U-naphthol 3.6 g, acetic anhydride 3 mL, sodium bisulfate 0.5 g, temperature 80℃, reaction time 40 min. The method has advantages of cheapness and simplicity, and the catalyst can be easily regenerated.
U-Naphthyl acetate was synthesized in yield of 96.8% using sodium bisulfate as catalyst. The optimum conditions were as follows: U-naphthol 3.6 g, acetic anhydride 3 mL, sodium bisulfate 0.5 g, temperature 80℃, reaction time 40 min. The method has advantages of cheapness and simplicity, and the catalyst can be easily regenerated.
