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2008 Volume 25 Issue 5
2008, 25(5): 505-509
Abstract:
Four new second-order nonlinear optical (NLO) molecules derivated from thiazole and containing the structure of Schiff base were synthesized.These target molecules were confirmed by IR,UV,NMR and elemental analysis,and 2nd-order polarizability of those molecules were determined by a solvatochromic method.The structure of a five-membered heterocyclic ring and Schiff base improved the thermally stability and transparency,and the nonsymmetric conformation of thiazloe could link many donors and acceptors and thus improves the β value.Experimental results show that the maximum absorption wavelength was 350~415 nm,the decomposition temperature was about 300℃,and the β value was 1×10-30 esu,indicating a good nonlinearity-transparency-thermally stable comprehensive optimization has been achieved.
Four new second-order nonlinear optical (NLO) molecules derivated from thiazole and containing the structure of Schiff base were synthesized.These target molecules were confirmed by IR,UV,NMR and elemental analysis,and 2nd-order polarizability of those molecules were determined by a solvatochromic method.The structure of a five-membered heterocyclic ring and Schiff base improved the thermally stability and transparency,and the nonsymmetric conformation of thiazloe could link many donors and acceptors and thus improves the β value.Experimental results show that the maximum absorption wavelength was 350~415 nm,the decomposition temperature was about 300℃,and the β value was 1×10-30 esu,indicating a good nonlinearity-transparency-thermally stable comprehensive optimization has been achieved.
2008, 25(5): 510-513
Abstract:
Electron spray ionization mass spectrometry (ESI-MS) was employed for direct investigation of arsenazo Ⅲ aqueous solutions.Experimentally,it was found that arsenazo Ⅲ formed singly (m/z 775) or doubly charged ions (m/z 387) by deprotonation in the ESI process.Under the experimental conditions,the signal of m/z 387 was 20 times higher than that of m/z 775.The formation of the negative ions of arsenazo Ⅲ was favored in weakly acidic solution.The characteristic fragmentation patterns of the anions (i.e.,m/z 775,m/z 387) of arsenazo Ⅲ were obtained by multiple stage tandem mass spectrometry with a collision energy of 15%~25%,providing evidence for identifying arsenazo Ⅲ in a complex mixture.The data showed that a low limit detection of 0.74×10-15 g was obtained with tandem mass spectrometry for the doubly charged anions (m/z 387),showing that electrospray ionization tandem mass spectrometry is a useful tool for the study and detection of arsenazo Ⅲ.
Electron spray ionization mass spectrometry (ESI-MS) was employed for direct investigation of arsenazo Ⅲ aqueous solutions.Experimentally,it was found that arsenazo Ⅲ formed singly (m/z 775) or doubly charged ions (m/z 387) by deprotonation in the ESI process.Under the experimental conditions,the signal of m/z 387 was 20 times higher than that of m/z 775.The formation of the negative ions of arsenazo Ⅲ was favored in weakly acidic solution.The characteristic fragmentation patterns of the anions (i.e.,m/z 775,m/z 387) of arsenazo Ⅲ were obtained by multiple stage tandem mass spectrometry with a collision energy of 15%~25%,providing evidence for identifying arsenazo Ⅲ in a complex mixture.The data showed that a low limit detection of 0.74×10-15 g was obtained with tandem mass spectrometry for the doubly charged anions (m/z 387),showing that electrospray ionization tandem mass spectrometry is a useful tool for the study and detection of arsenazo Ⅲ.
2008, 25(5): 514-518
Abstract:
CePW nanoparticles supported on multi-wall carbon nanotubes were prepared,and modified onto a glassy carbon electrode.Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to characterize the electrode.The electrochemical behavior of dopamine at this modified electrode was investigated,and the result showed that it gave reversible redox peaks at a formal potential of 0.173 V(pH=6.0).The anodic peak current (measured with constant potential amperometry) increased linearly with the increased concentration of dopamine in a range of 5.0×10-7 to 5.0×10-3 mol/L and the linear regression equation was ip(μA)=-0.954 2+0.056 02c(μmol/L).The detection limit (S/N=3) obtained was 3.3×10-8 mol/L.The interference of ascorbic acid to the determination of DA could be eliminated efficiently.The proposed method showed excellent sensitivity and recovery.
CePW nanoparticles supported on multi-wall carbon nanotubes were prepared,and modified onto a glassy carbon electrode.Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to characterize the electrode.The electrochemical behavior of dopamine at this modified electrode was investigated,and the result showed that it gave reversible redox peaks at a formal potential of 0.173 V(pH=6.0).The anodic peak current (measured with constant potential amperometry) increased linearly with the increased concentration of dopamine in a range of 5.0×10-7 to 5.0×10-3 mol/L and the linear regression equation was ip(μA)=-0.954 2+0.056 02c(μmol/L).The detection limit (S/N=3) obtained was 3.3×10-8 mol/L.The interference of ascorbic acid to the determination of DA could be eliminated efficiently.The proposed method showed excellent sensitivity and recovery.
2008, 25(5): 519-523
Abstract:
A new surface desorption atmospheric chemical ionization mass spectrometry (SDAPCI-MS) method was established to directly fingerprint various tea products with neither sample pre-treatment nor toxic chemical contamination.Four tea products,LuShanYunWu,TieGuanYin,QiMenHongCha,and PuErCha,were successfully analyzed based on their unique mass spectral fingerprints.The identification of the molecular structure of interested ions was demonstrated by multiple-stage SDAPCI mass spectrometry.The SDAPCI spectral fingerprints of the four tea products did not change significantly after they were stored for three months at room temperature.The analysis time was less than 1 s for any single sample,and SDAPCI-MS can be operated online continuously.Clearly,SDAPCI-MS with water vapor in the atmosphere as ionization reagent can detect both volatile and non-volatile chemicals from tea product surfaces at ambient pressure,showing its potential in fast and nondestructive analysis of bulk samples.
A new surface desorption atmospheric chemical ionization mass spectrometry (SDAPCI-MS) method was established to directly fingerprint various tea products with neither sample pre-treatment nor toxic chemical contamination.Four tea products,LuShanYunWu,TieGuanYin,QiMenHongCha,and PuErCha,were successfully analyzed based on their unique mass spectral fingerprints.The identification of the molecular structure of interested ions was demonstrated by multiple-stage SDAPCI mass spectrometry.The SDAPCI spectral fingerprints of the four tea products did not change significantly after they were stored for three months at room temperature.The analysis time was less than 1 s for any single sample,and SDAPCI-MS can be operated online continuously.Clearly,SDAPCI-MS with water vapor in the atmosphere as ionization reagent can detect both volatile and non-volatile chemicals from tea product surfaces at ambient pressure,showing its potential in fast and nondestructive analysis of bulk samples.
2008, 25(5): 524-528
Abstract:
Six low-molecular-mass organic gelators were synthesized by the condensation reaction of sorbitol and derived benzenaldehyde with p-TsOH as catalyst.They are 1,3:2,4-dibenzylidene-D-sorbitol (DBS),1,3:2,4-di(4-methylbenzylidene)-D-sorbitol (MDBS),1,3:2,4-di(3,4-dimethylbenzylidene)-D-sorbitol (DMDBS),1,3:2,4-di(2,4,6-trimethylbenzylidene)-D-sorbitol(2,4,6-TMDBS),1,3:2,4-di(2,4,5-trimethylbenzylidene)-D-sorbitol (2,4,5-TMDBS) and 1,3:2,4-di(5,6,7,8-tetrahydronathalenyl-2-methylene)-D-sorbitol(DTNHS),and the yield is 30.9%~91.2%.Physical or chemical method was used to remove the water formed during the reaction.Structures of the targets were determined by 1H NMR.Thermoreversible organogels were prepared with various organic solvent.The gel-sol phase transition temperature of gels was characterized by DSC.The structure of the gels were characterized by TEM and XRD.The results show that the 3D networks were formed in the gels.The diameter of the fiber affects the transparency of the gels.The gelator in gels were non-crystal in whole,but microcrystallite zones exist in the 3D networks.
Six low-molecular-mass organic gelators were synthesized by the condensation reaction of sorbitol and derived benzenaldehyde with p-TsOH as catalyst.They are 1,3:2,4-dibenzylidene-D-sorbitol (DBS),1,3:2,4-di(4-methylbenzylidene)-D-sorbitol (MDBS),1,3:2,4-di(3,4-dimethylbenzylidene)-D-sorbitol (DMDBS),1,3:2,4-di(2,4,6-trimethylbenzylidene)-D-sorbitol(2,4,6-TMDBS),1,3:2,4-di(2,4,5-trimethylbenzylidene)-D-sorbitol (2,4,5-TMDBS) and 1,3:2,4-di(5,6,7,8-tetrahydronathalenyl-2-methylene)-D-sorbitol(DTNHS),and the yield is 30.9%~91.2%.Physical or chemical method was used to remove the water formed during the reaction.Structures of the targets were determined by 1H NMR.Thermoreversible organogels were prepared with various organic solvent.The gel-sol phase transition temperature of gels was characterized by DSC.The structure of the gels were characterized by TEM and XRD.The results show that the 3D networks were formed in the gels.The diameter of the fiber affects the transparency of the gels.The gelator in gels were non-crystal in whole,but microcrystallite zones exist in the 3D networks.
2008, 25(5): 529-533
Abstract:
MgCl2·6H2O was used as raw material.Sodium hydroxide was used as precipitator.Factors influencing the formation of Mg(OH)2 whisker,such as concentration ratio of MgCl2·6H2O to NaOH,reaction temperature,crystallization temperature,crystallization time,crystallization means were tested.Experimental results show that the preliminary and undergrown Mg(OH)2 whisker can be obtained under the conditions of n(MgCl2):n(NaOH)=1.20:1.92,reaction temperature Tm=86℃,crystallization temperature Tc=100℃,crystallization time 5.5 h.Under the same conditions,better whisker can be obtained when hydrothermal crystallization is used.On this foundation,a perfect Mg(OH)2 whisker was achieved after the organic solvent was added into NaOH solution.The SEM reveals that the particle of Mg(OH)2 has whisker form with fine dispersive capability and perfect crystal form,as well as high purity and uniform particle size.The whisker growth mechanism was preliminarily analyzed.
MgCl2·6H2O was used as raw material.Sodium hydroxide was used as precipitator.Factors influencing the formation of Mg(OH)2 whisker,such as concentration ratio of MgCl2·6H2O to NaOH,reaction temperature,crystallization temperature,crystallization time,crystallization means were tested.Experimental results show that the preliminary and undergrown Mg(OH)2 whisker can be obtained under the conditions of n(MgCl2):n(NaOH)=1.20:1.92,reaction temperature Tm=86℃,crystallization temperature Tc=100℃,crystallization time 5.5 h.Under the same conditions,better whisker can be obtained when hydrothermal crystallization is used.On this foundation,a perfect Mg(OH)2 whisker was achieved after the organic solvent was added into NaOH solution.The SEM reveals that the particle of Mg(OH)2 has whisker form with fine dispersive capability and perfect crystal form,as well as high purity and uniform particle size.The whisker growth mechanism was preliminarily analyzed.
2008, 25(5): 534-538
Abstract:
Water-soluble Cysteamine-capped-CdS nanoparticles were prepared in aqueous solution at room temperature,and characterized by atomic force microscopy,scanning electron microscopy,Fourier transform infrared spectrometry,Ultraviolet-visible spectrometry,and spectrofluorimetry,respectively.A new approach was proposed for the sensitive determination of manganese ion with nanoparticles as the fluorescence probe.Different influencing factors were studied,including the concentration and pH of buffer,reaction time,and concentration of the nanoparticles.Under the optimum conditions,the response was linearly proportional to the concentration of manganese (Ⅱ) ion in a range of 0.053 40 mg/L to 77.62 mg/L.The detection limit was 0.016 78 mg/L for manganese (Ⅱ) ion.And it was proved to be a low-cost,simple,rapid,sensitive,low-limit method.Functionalized nanoparticles are hopeful to use as fluorescence probe in detecting trace elements in biological samples.
Water-soluble Cysteamine-capped-CdS nanoparticles were prepared in aqueous solution at room temperature,and characterized by atomic force microscopy,scanning electron microscopy,Fourier transform infrared spectrometry,Ultraviolet-visible spectrometry,and spectrofluorimetry,respectively.A new approach was proposed for the sensitive determination of manganese ion with nanoparticles as the fluorescence probe.Different influencing factors were studied,including the concentration and pH of buffer,reaction time,and concentration of the nanoparticles.Under the optimum conditions,the response was linearly proportional to the concentration of manganese (Ⅱ) ion in a range of 0.053 40 mg/L to 77.62 mg/L.The detection limit was 0.016 78 mg/L for manganese (Ⅱ) ion.And it was proved to be a low-cost,simple,rapid,sensitive,low-limit method.Functionalized nanoparticles are hopeful to use as fluorescence probe in detecting trace elements in biological samples.
2008, 25(5): 539-542
Abstract:
Ethyl 5-phenyl-1H-pyrazole-3-carboxylate was synthesized by one-pot reaction method,and was used further for the synthesis of nine 5-phenyl-1H-3-pyrazole hydrazones,which were characterized by elemental analysis,IR and 1H NMR.Furthermore,a trinuclear copper complex was obtained in the monoclinic space group of C2/c with cell dimensions of a=2.576 7(3) nm,b=1.194 42(15) nm,c=14.126 5(17) nm,β=98.993(2)°,V=4.294 1(9) nm3,Z=4,Dc=1.629 g/cm3 and R1=0.035 5 by the reaction of Cu(AcO)2 and 5-phenyl-1H-pyrazole-3-carboxylic acid which was obtained by hydrolysis of ethyl 5-phenyl-1H-pyrazole-3-carboxylate,and as a result the molecular structure of pyrazole was confirmed.
Ethyl 5-phenyl-1H-pyrazole-3-carboxylate was synthesized by one-pot reaction method,and was used further for the synthesis of nine 5-phenyl-1H-3-pyrazole hydrazones,which were characterized by elemental analysis,IR and 1H NMR.Furthermore,a trinuclear copper complex was obtained in the monoclinic space group of C2/c with cell dimensions of a=2.576 7(3) nm,b=1.194 42(15) nm,c=14.126 5(17) nm,β=98.993(2)°,V=4.294 1(9) nm3,Z=4,Dc=1.629 g/cm3 and R1=0.035 5 by the reaction of Cu(AcO)2 and 5-phenyl-1H-pyrazole-3-carboxylic acid which was obtained by hydrolysis of ethyl 5-phenyl-1H-pyrazole-3-carboxylate,and as a result the molecular structure of pyrazole was confirmed.
2008, 25(5): 543-547
Abstract:
The battery grade Co3O4 was prepared from CoCl2·6H2O and NH4HCO3 by means of precipitation and calcination.Systemic studies were conducted on the effects of pH of the solution,reaction time and temperature,the adding ratio of raw materials during the reaction process,and the calcination period and temperature of the precursor basic cobalt carbonate.The best preparation way was thus found.The precursor basic cobalt carbonate was made from the reaction between CoCl2·6H2O and NH4HCO3 with the molar ratio of 1:2.5,at 80℃ or so and pH 8~9 for 20 minutes.Then,the precursor basic cobalt carbonate was washed with de-ionized water,dried by heating or air flowing at a temperature less than 100℃,and baked at a temperature from 600 to 820℃ for about 8 h.Thus,the pure Co3O4 was made.Co3O4 powder characterization was analyzed by ICP-AES,XRD,SEM/EDS,FT-IR,LGA,and TG/DSC.It was found by the characterization study that the Co3O4 powder was at particle size ranging from 4~10 μm,average grain size of 7.3 μm,and specific area of 1.05 m2/g.The powder showed a narrow distribution of particle size,and was polyhedral and sphereoidal,and met the requirement of the battery grade Co3O4.
The battery grade Co3O4 was prepared from CoCl2·6H2O and NH4HCO3 by means of precipitation and calcination.Systemic studies were conducted on the effects of pH of the solution,reaction time and temperature,the adding ratio of raw materials during the reaction process,and the calcination period and temperature of the precursor basic cobalt carbonate.The best preparation way was thus found.The precursor basic cobalt carbonate was made from the reaction between CoCl2·6H2O and NH4HCO3 with the molar ratio of 1:2.5,at 80℃ or so and pH 8~9 for 20 minutes.Then,the precursor basic cobalt carbonate was washed with de-ionized water,dried by heating or air flowing at a temperature less than 100℃,and baked at a temperature from 600 to 820℃ for about 8 h.Thus,the pure Co3O4 was made.Co3O4 powder characterization was analyzed by ICP-AES,XRD,SEM/EDS,FT-IR,LGA,and TG/DSC.It was found by the characterization study that the Co3O4 powder was at particle size ranging from 4~10 μm,average grain size of 7.3 μm,and specific area of 1.05 m2/g.The powder showed a narrow distribution of particle size,and was polyhedral and sphereoidal,and met the requirement of the battery grade Co3O4.
2008, 25(5): 548-551
Abstract:
With the column of 0.07~0.05 mm silica gel,the separation of perphenylcarbamoylated β-cyclodextrin was investigated.The effects of mobile phase composition,bed volume,sample load,flow rate and column temperature on separation were studied systematically.The mixture was separated and the optimal conditions were obtained.The best technological conditions are approached:the bed height is 32 cm;the mobile phase is V(hexane):V(ethyl acetate)=2:1;the flow rate is 0.6 mL/min;the column temperature is 30℃;and the maximal sample load is 0.02 g.With these conditions,the recovery was 40.91% of first eluent and 50% of last eluent,respectively.
With the column of 0.07~0.05 mm silica gel,the separation of perphenylcarbamoylated β-cyclodextrin was investigated.The effects of mobile phase composition,bed volume,sample load,flow rate and column temperature on separation were studied systematically.The mixture was separated and the optimal conditions were obtained.The best technological conditions are approached:the bed height is 32 cm;the mobile phase is V(hexane):V(ethyl acetate)=2:1;the flow rate is 0.6 mL/min;the column temperature is 30℃;and the maximal sample load is 0.02 g.With these conditions,the recovery was 40.91% of first eluent and 50% of last eluent,respectively.
2008, 25(5): 552-555
Abstract:
Eightnovel N'-tertbutylaminocarbonyl-N-5-substitutedphenyl-2-furylformylthiourea derivatives were synthesized by taking active group 5-substitutedphenyl furan and tert-butylamino into the acylthiourea.Their structures were elucidated and confirmed by elemental analysis,IR,and 1H NMR.The inhibitory rate of cellular growth of K562 cells was measured via MTT assay.The results indicated that the title compounds have some effects on the cellular growth inhibition to K562 cells of leukemia.
Eightnovel N'-tertbutylaminocarbonyl-N-5-substitutedphenyl-2-furylformylthiourea derivatives were synthesized by taking active group 5-substitutedphenyl furan and tert-butylamino into the acylthiourea.Their structures were elucidated and confirmed by elemental analysis,IR,and 1H NMR.The inhibitory rate of cellular growth of K562 cells was measured via MTT assay.The results indicated that the title compounds have some effects on the cellular growth inhibition to K562 cells of leukemia.
Preparation of Stigmasterol Molecular Imprinting Polymeric Microspheres by Suspension Polymerization
2008, 25(5): 556-559
Abstract:
The molecular imprinting polymeric microspheres (MIPs) of stignmasterol were prepared by suspension polymerization,with stignmasterol as the printing molecule,methyl methacrylate (MMA) and methacrylic acid (MAA) as the functional monomers,vinyl benzene (VB) as the cross-linker,CaCO3 and SDS as the dispersants,and Na2S2O8 as the initiator.The average diameter was below 100 μm and the size distribution was narrow.The experiment results showed that the optimal recipe was 3 g stig.:40 mL MMA or 30 mL MMA+10 mL MAA:15 mL VB:4 g CaCO3+2 g SDS.During the polymerization Na2S2O8 was added batchwise,and in the early period a high speed stirring was applied,and with the going of the polymerization,the stirring rate was reduced.With a separation factor of over 1.65 and an adsorption capacity of 1.28 mg/g,the prepared MIPs had a strong selective adsorption toward stigmasterol.
The molecular imprinting polymeric microspheres (MIPs) of stignmasterol were prepared by suspension polymerization,with stignmasterol as the printing molecule,methyl methacrylate (MMA) and methacrylic acid (MAA) as the functional monomers,vinyl benzene (VB) as the cross-linker,CaCO3 and SDS as the dispersants,and Na2S2O8 as the initiator.The average diameter was below 100 μm and the size distribution was narrow.The experiment results showed that the optimal recipe was 3 g stig.:40 mL MMA or 30 mL MMA+10 mL MAA:15 mL VB:4 g CaCO3+2 g SDS.During the polymerization Na2S2O8 was added batchwise,and in the early period a high speed stirring was applied,and with the going of the polymerization,the stirring rate was reduced.With a separation factor of over 1.65 and an adsorption capacity of 1.28 mg/g,the prepared MIPs had a strong selective adsorption toward stigmasterol.
2008, 25(5): 560-563
Abstract:
A series of β-elemene monosubstituted amino acid derivatives were synthesized from the reaction of β-elemene with each of seven different amino acids under basic condition at 66℃,and their structures were characterized by IR,1H NMR,and HRMS.Sodium hypochloride added in this step should be 2 equivalent of the reacted β-elemene.The β-elemene monosubstituted amino acid derivatives were prepared from the unprotected amino acids with ethanol and water as solvent (V(EtOH):V(H2O)=4:1).The effects of temperature on reaction yield showed that more byproducts would appear at higher temperatures and the reaction would run much slower at low temperatures.
A series of β-elemene monosubstituted amino acid derivatives were synthesized from the reaction of β-elemene with each of seven different amino acids under basic condition at 66℃,and their structures were characterized by IR,1H NMR,and HRMS.Sodium hypochloride added in this step should be 2 equivalent of the reacted β-elemene.The β-elemene monosubstituted amino acid derivatives were prepared from the unprotected amino acids with ethanol and water as solvent (V(EtOH):V(H2O)=4:1).The effects of temperature on reaction yield showed that more byproducts would appear at higher temperatures and the reaction would run much slower at low temperatures.
2008, 25(5): 564-568
Abstract:
Chitosan/5-fluorouracil nanoparticles (CS/5-Fu NPs) were prepared by microemulsion-ionic crosslinking method with Na2SO4 and Na5P3O10 used as crosslinkers.These NPs were monodispersed and uniformly spherical.NPs prepared by Na2SO4 were about 100 nm in size,with the drug loading efficiency (LE) and ecapsulation efficiency (EE) amounting to 30% and 80%,respectively.NPs prepared by Na5P3O10 were 40~80 nm in size,with LE and EE amounting to 21% and 55%,respectively.Sustained-release experiment was carried out in HCl solution (pH=1) and phosphate buffered solution (pH=7.4),which showed that the drug releasing amount increased with the releasing time extended,and the drug releasing performance was better in phosphate buffered solution.When cultured with the NPs,the apoptosis of K562 tumor cells was increased with the releasing time extended,which indicated that the drug releasing amount of NPs in the culture solution was increased with extended cultured time,and that the tumor cells were induced to apoptosis distinctively.
Chitosan/5-fluorouracil nanoparticles (CS/5-Fu NPs) were prepared by microemulsion-ionic crosslinking method with Na2SO4 and Na5P3O10 used as crosslinkers.These NPs were monodispersed and uniformly spherical.NPs prepared by Na2SO4 were about 100 nm in size,with the drug loading efficiency (LE) and ecapsulation efficiency (EE) amounting to 30% and 80%,respectively.NPs prepared by Na5P3O10 were 40~80 nm in size,with LE and EE amounting to 21% and 55%,respectively.Sustained-release experiment was carried out in HCl solution (pH=1) and phosphate buffered solution (pH=7.4),which showed that the drug releasing amount increased with the releasing time extended,and the drug releasing performance was better in phosphate buffered solution.When cultured with the NPs,the apoptosis of K562 tumor cells was increased with the releasing time extended,which indicated that the drug releasing amount of NPs in the culture solution was increased with extended cultured time,and that the tumor cells were induced to apoptosis distinctively.
2008, 25(5): 569-572
Abstract:
The terbium doped TiO2 pillared bentonites (Tb-TiO2-PILCs) were prepared with Ti(i-C3H7O)4 and Tb2O3 as precursors by the sol-gel method.Characteristics of Tb-TiO2-PILCs were examined with XRD and BET.Tb-TiO2-PILCs were used as composite photocatalysts for the photocatalytic degradation of sodium pentachlorophenate (PCP-Na).The results indicate that all the pillared bentonites contain TiO2 in the anatase phase.The photocatalytic activities of Tb-TiO2-PILCs are superior to that of non doped TiO2-PILC.Tb-TiO2-PILC shows the most photocatalytic activity when the mass percent of Tb/Ti is 0.5% among all the catalysts.In addition,the experiments also illustrate that the composite photocatalysts can be easily recovered,regenerated and reused.
The terbium doped TiO2 pillared bentonites (Tb-TiO2-PILCs) were prepared with Ti(i-C3H7O)4 and Tb2O3 as precursors by the sol-gel method.Characteristics of Tb-TiO2-PILCs were examined with XRD and BET.Tb-TiO2-PILCs were used as composite photocatalysts for the photocatalytic degradation of sodium pentachlorophenate (PCP-Na).The results indicate that all the pillared bentonites contain TiO2 in the anatase phase.The photocatalytic activities of Tb-TiO2-PILCs are superior to that of non doped TiO2-PILC.Tb-TiO2-PILC shows the most photocatalytic activity when the mass percent of Tb/Ti is 0.5% among all the catalysts.In addition,the experiments also illustrate that the composite photocatalysts can be easily recovered,regenerated and reused.
2008, 25(5): 573-577
Abstract:
Micron-sized silica gel was chemically modified with 3-methacryloxypropyl trimethoxysilane (MPTMS,KH-570) as coupling agent.Double bonds were introduced onto the surface of silica gel particles,and modified particles MPS-SiO2 were obtained.The poly methyl acrylic acid (PMMA) was grafted on the surface of particles MPS-SiO2 with the method of "graft from" ,and grafted particles PMMA/SiO2 were prepared.The chemical structure of the grafed particle PMMA/SiO2 was characterized by means of infrared spectroscopy (FTIR) and thermogravimetry (TG),and the morphology of the grafting particle PMMA/SiO2 was observed.The experimental results show that the graft polymerization of methyl acrylic acid (MAA) onto the surface of silica gel particles can be successfully realized with the method of "graft from" .During the graft polymerization,the grafted polymer layer was a hindrance to the subsequent graft polymerization.When the grafted polymer layer reached to a certain density via overlapping and entwisting,a kinetic barrier was built up.There were several factors affecting the grafting degree of polymer,such as monomer concentration,initiator amount and temperature.The grafting degree of polymer increased with the increase of the monomer concentration,and the grafting degree unchanged when the concentration of monomer was over 3%.When the amount of initiator increased or temperature rose,the grafting degree of polymer firstly increased and then decreased.The preparation conditions for the maximum grafting degree were temperature was 70℃,the concentration of monomer was 3% and the amount of initiator was 0.6%.
Micron-sized silica gel was chemically modified with 3-methacryloxypropyl trimethoxysilane (MPTMS,KH-570) as coupling agent.Double bonds were introduced onto the surface of silica gel particles,and modified particles MPS-SiO2 were obtained.The poly methyl acrylic acid (PMMA) was grafted on the surface of particles MPS-SiO2 with the method of "graft from" ,and grafted particles PMMA/SiO2 were prepared.The chemical structure of the grafed particle PMMA/SiO2 was characterized by means of infrared spectroscopy (FTIR) and thermogravimetry (TG),and the morphology of the grafting particle PMMA/SiO2 was observed.The experimental results show that the graft polymerization of methyl acrylic acid (MAA) onto the surface of silica gel particles can be successfully realized with the method of "graft from" .During the graft polymerization,the grafted polymer layer was a hindrance to the subsequent graft polymerization.When the grafted polymer layer reached to a certain density via overlapping and entwisting,a kinetic barrier was built up.There were several factors affecting the grafting degree of polymer,such as monomer concentration,initiator amount and temperature.The grafting degree of polymer increased with the increase of the monomer concentration,and the grafting degree unchanged when the concentration of monomer was over 3%.When the amount of initiator increased or temperature rose,the grafting degree of polymer firstly increased and then decreased.The preparation conditions for the maximum grafting degree were temperature was 70℃,the concentration of monomer was 3% and the amount of initiator was 0.6%.
2008, 25(5): 578-582
Abstract:
Electrochemical behavior and electrochemical kinetic parameters of LSP at carbon paste electrode (CPE) were investigated by cyclic voltammetry (CV),chronoamperometry (CA),and chronocoulometry (CC).Electrochemical experimental results showed that LSP in 0.10 mol/L PBS exhibited an irreversible electrochemical redox process at CPE,and the oxidation peak potential (Epa) was 0.956 V.The plots of oxidation peak current versus the square root of the scanning rate for the redox in a potential range of 10~1 000 mV/s were linear,as expected for a diffusion-limited electrochemical process for LSP electrochemical oxidation.Electron transfer coefficient α,diffusion coefficient D,and apparent reaction rate constant kf were 0.77,2.47×10-5 cm2/s and 3.46×10-3 cm/s,respectively.The chang of the oxidation peak current with LSP concentration was examined by Square wave voltammetry (SWV).The oxidation peak current of LSP versus its concentration showed a good linear relationship in a concentration range of 1.0×10-6~5.6×10-3 mol/L with a correlation coefficient of 0.999 8 and a detection limit of 5.0×10-7 mol/L by SWV response.The relative standard deviation was between 1.9%~2.3%,and the recovery was in a range of 98%~102%.The proposed method were applied to the determination of LSP in capsule samples with satisfied results.
Electrochemical behavior and electrochemical kinetic parameters of LSP at carbon paste electrode (CPE) were investigated by cyclic voltammetry (CV),chronoamperometry (CA),and chronocoulometry (CC).Electrochemical experimental results showed that LSP in 0.10 mol/L PBS exhibited an irreversible electrochemical redox process at CPE,and the oxidation peak potential (Epa) was 0.956 V.The plots of oxidation peak current versus the square root of the scanning rate for the redox in a potential range of 10~1 000 mV/s were linear,as expected for a diffusion-limited electrochemical process for LSP electrochemical oxidation.Electron transfer coefficient α,diffusion coefficient D,and apparent reaction rate constant kf were 0.77,2.47×10-5 cm2/s and 3.46×10-3 cm/s,respectively.The chang of the oxidation peak current with LSP concentration was examined by Square wave voltammetry (SWV).The oxidation peak current of LSP versus its concentration showed a good linear relationship in a concentration range of 1.0×10-6~5.6×10-3 mol/L with a correlation coefficient of 0.999 8 and a detection limit of 5.0×10-7 mol/L by SWV response.The relative standard deviation was between 1.9%~2.3%,and the recovery was in a range of 98%~102%.The proposed method were applied to the determination of LSP in capsule samples with satisfied results.
2008, 25(5): 583-586
Abstract:
Under acidic condition,the nitrogen atom in propantheline bromide was easily protonated and formed ion-complex with negative ion AuCl4-.The ion-complex was extacted with dichloromethane.When the ion-complex entered a reversed micellar microemulsion of cetyltrimethylammonium chlorine containing luminol,the dissociated AuCl4- reacted with luminol,producing an analytical chemiluminescnece signal.Under the optimum conditions,the linear range is from 0.001 to 10×10-6 g/mL and the limit of detection is 0.04×10-9 g/mL with a relative standard deviation (n=11) of ca.1.32% for 1.0×10-6 g/mL propantheline bromide.The method has been applied to the determination of the studied drug in tablets and biological fluids successfully.
Under acidic condition,the nitrogen atom in propantheline bromide was easily protonated and formed ion-complex with negative ion AuCl4-.The ion-complex was extacted with dichloromethane.When the ion-complex entered a reversed micellar microemulsion of cetyltrimethylammonium chlorine containing luminol,the dissociated AuCl4- reacted with luminol,producing an analytical chemiluminescnece signal.Under the optimum conditions,the linear range is from 0.001 to 10×10-6 g/mL and the limit of detection is 0.04×10-9 g/mL with a relative standard deviation (n=11) of ca.1.32% for 1.0×10-6 g/mL propantheline bromide.The method has been applied to the determination of the studied drug in tablets and biological fluids successfully.
2008, 25(5): 587-591
Abstract:
Interpenetrating polymer network (IPN) hydrogels composed of waterborne polyurethane (WPU) and polyacrylamide (PAAm) were synthesized.Crosslinked WPU was synthesised from IPDI,N220,DMPA and TMP.Then AAm,DEGDA as crosslinking agent and potassium persulfate (KPS) as initiator were added to form the IPN waterborne polyurethane-polyacrylamide (PU-PAAm) hydrogels.IR,DSC,TEM and the swelling ratio of the hydrogels indicated that the PU-PAAm had cell-like structure,and the components exhibited good compatibility.PU-PAAm IPN hydrogels showed synergistic effect,with the synthesized hydrogel with m(PU):m(PAAm)=50:60 showing the highest SR of 11.16.TNO,ZX-10 and chitosan were respectively loaded in the hydrogels,and the hydrogels carrying TNO and ZX-10 showed good antibacterial activity.
Interpenetrating polymer network (IPN) hydrogels composed of waterborne polyurethane (WPU) and polyacrylamide (PAAm) were synthesized.Crosslinked WPU was synthesised from IPDI,N220,DMPA and TMP.Then AAm,DEGDA as crosslinking agent and potassium persulfate (KPS) as initiator were added to form the IPN waterborne polyurethane-polyacrylamide (PU-PAAm) hydrogels.IR,DSC,TEM and the swelling ratio of the hydrogels indicated that the PU-PAAm had cell-like structure,and the components exhibited good compatibility.PU-PAAm IPN hydrogels showed synergistic effect,with the synthesized hydrogel with m(PU):m(PAAm)=50:60 showing the highest SR of 11.16.TNO,ZX-10 and chitosan were respectively loaded in the hydrogels,and the hydrogels carrying TNO and ZX-10 showed good antibacterial activity.
2008, 25(5): 592-595
Abstract:
The effects of initiator system,emulsifier type and amount,reaction temperature,and electrolyte on monomer conversion,coagulum content,particle size and distribution for the emulsion polymerization of the water-soluble 2-hydroxyethyl methacrylate (HEMA) were investigated.The results showed the oil-soluble initiator azoisobutyronitrile (AIBN) may increase the monomer conversion and decrease the coagulum;the amount of the emulsifier had little effect on the monomer conversion,but the coagulum greatly decreased with the increase of the amount of the emulsifier.As the reaction temperature increased from 65℃ to 85℃,the monomer conversion increased first and then decreased,and the coagulum increased continuously,and the ideal reaction temperature was 75℃.The presence of electrolyte,NaHCO3,decreased the monomer conversion;the particle distribution index was broader and multimodal distributions were observed.
The effects of initiator system,emulsifier type and amount,reaction temperature,and electrolyte on monomer conversion,coagulum content,particle size and distribution for the emulsion polymerization of the water-soluble 2-hydroxyethyl methacrylate (HEMA) were investigated.The results showed the oil-soluble initiator azoisobutyronitrile (AIBN) may increase the monomer conversion and decrease the coagulum;the amount of the emulsifier had little effect on the monomer conversion,but the coagulum greatly decreased with the increase of the amount of the emulsifier.As the reaction temperature increased from 65℃ to 85℃,the monomer conversion increased first and then decreased,and the coagulum increased continuously,and the ideal reaction temperature was 75℃.The presence of electrolyte,NaHCO3,decreased the monomer conversion;the particle distribution index was broader and multimodal distributions were observed.
2008, 25(5): 596-600
Abstract:
Mesoporous alumina (MA) was prepared by a neutral synthesis route.Catalysts (KF/MA) were prepared with MA as support for deposition of potassium fluoride via impregnation.The samples of supports and catalysts were characterized by XRD,N2 adsorption,TEM,FTIR and Hammett titration.The mesoporous alumina samples synthesized by neutral pathway exhibited a wormhole channel motif,and the surface area was 375 m2/g,and the average pore size was 7.1 nm,and the catalyst possessed a 36.7% KF loading and a basic intensity over 18.4 and a basicity of 3.64 mmol/g.The KF/MA catalysts were employed as highly active/selective catalysts for the O-alkylation reaction of p,p'-biphenol.The results indicated that the catalytic activity was influenced strongly by the support.The catalytic activity of KF/MA was better than that of KF/γ-Al2O3.
Mesoporous alumina (MA) was prepared by a neutral synthesis route.Catalysts (KF/MA) were prepared with MA as support for deposition of potassium fluoride via impregnation.The samples of supports and catalysts were characterized by XRD,N2 adsorption,TEM,FTIR and Hammett titration.The mesoporous alumina samples synthesized by neutral pathway exhibited a wormhole channel motif,and the surface area was 375 m2/g,and the average pore size was 7.1 nm,and the catalyst possessed a 36.7% KF loading and a basic intensity over 18.4 and a basicity of 3.64 mmol/g.The KF/MA catalysts were employed as highly active/selective catalysts for the O-alkylation reaction of p,p'-biphenol.The results indicated that the catalytic activity was influenced strongly by the support.The catalytic activity of KF/MA was better than that of KF/γ-Al2O3.
2008, 25(5): 601-604
Abstract:
The effects of ion types,temperature and scale size on the barium sulfate scale elimination were investigated by means of applying ionic liquids with different properties to descale barium sulfate scale.The results show that the ionic liquid CH2CH3)3NHAl2Cl7 has a better dissolvability and a higher dissolving rate for the barium sulfate scale,which is enhanced greatly with the increase in the temperature and the decrease in the scale size (when the temperature increases from 60℃ to 70℃ and the size of the scale decreases from 600~1 000 μm to 100~200 μm,then the descaling rate increases from 5.00% to 31.6%).The types of cation and anion in the ionic liquid affect the scale elimination greatly.The dissolving effect of hydrophilic ionic liquid CH2CH3)3NHAl2Cl7 with higher nonpolarity is much greater than that of the hydrophobic ionic liquid[BMIM]PF6 with higher polarity (under the same condition,the descaling rate of CH2CH3)3NHAl2Cl7 is 22.45%,but the descaling rate of[BMIM]PF6 is only 0.47%).Meanwhile the descaling effect of ionic liquid CH2CH3)3NHAl2Cl7 for barium sulfate scale is more obvious than that for the calcium carbonate scale.
The effects of ion types,temperature and scale size on the barium sulfate scale elimination were investigated by means of applying ionic liquids with different properties to descale barium sulfate scale.The results show that the ionic liquid CH2CH3)3NHAl2Cl7 has a better dissolvability and a higher dissolving rate for the barium sulfate scale,which is enhanced greatly with the increase in the temperature and the decrease in the scale size (when the temperature increases from 60℃ to 70℃ and the size of the scale decreases from 600~1 000 μm to 100~200 μm,then the descaling rate increases from 5.00% to 31.6%).The types of cation and anion in the ionic liquid affect the scale elimination greatly.The dissolving effect of hydrophilic ionic liquid CH2CH3)3NHAl2Cl7 with higher nonpolarity is much greater than that of the hydrophobic ionic liquid[BMIM]PF6 with higher polarity (under the same condition,the descaling rate of CH2CH3)3NHAl2Cl7 is 22.45%,but the descaling rate of[BMIM]PF6 is only 0.47%).Meanwhile the descaling effect of ionic liquid CH2CH3)3NHAl2Cl7 for barium sulfate scale is more obvious than that for the calcium carbonate scale.
2008, 25(5): 605-608
Abstract:
Spherical polynaphthoxazine resin acid catalyst was prepared and applied to esterification reaction of glacial acetic acid and ethanol.Naphthoxazine precursor was converted into spherical polynaphthoxazine resin in methylsilicone oil by reversed-phase suspension polymerization,then polynaphthoxazine resin acid was generated from the reaction of sulfonation.Thermal stability and surface composition of the catalyst were measured by NETZSCH TG 209 and JSM-6390/LV SEM,respectively.Catalytic activity of the resin acid was evaluated through the esterification reaction of glacial acetic acid and ethanol.The results show that the pyrogenation of spherical polynaphthoxazine resin obtained by reversed-phase suspension polymerization will not take place at 300℃.Catalytic activity of the catalyst obtained from sulfonating spherical polynaphtho-xazine resin at 45℃ is the highest,and there is 4.29 mmol/g of sulfonic groups on the surface of resin.The conversion rate of glacial acetic acid was 77% with the catalyst obtained from sulfonation reaction at 45℃ when the reaction time was 2 h,catalyst dosage was 3% (on glacial acetic acid mass) and mole ratio of ethanol to acetic acid was 2:1.
Spherical polynaphthoxazine resin acid catalyst was prepared and applied to esterification reaction of glacial acetic acid and ethanol.Naphthoxazine precursor was converted into spherical polynaphthoxazine resin in methylsilicone oil by reversed-phase suspension polymerization,then polynaphthoxazine resin acid was generated from the reaction of sulfonation.Thermal stability and surface composition of the catalyst were measured by NETZSCH TG 209 and JSM-6390/LV SEM,respectively.Catalytic activity of the resin acid was evaluated through the esterification reaction of glacial acetic acid and ethanol.The results show that the pyrogenation of spherical polynaphthoxazine resin obtained by reversed-phase suspension polymerization will not take place at 300℃.Catalytic activity of the catalyst obtained from sulfonating spherical polynaphtho-xazine resin at 45℃ is the highest,and there is 4.29 mmol/g of sulfonic groups on the surface of resin.The conversion rate of glacial acetic acid was 77% with the catalyst obtained from sulfonation reaction at 45℃ when the reaction time was 2 h,catalyst dosage was 3% (on glacial acetic acid mass) and mole ratio of ethanol to acetic acid was 2:1.
2008, 25(5): 609-612
Abstract:
In this paper,the extraction behaviours of Pr(Ⅲ) and Nd(Ⅲ) from equeous chloride acid medium employing 8-hydroquiloine (HQ) were studied.Equilibrium constant (Kex) in the extraction of Pr(Ⅲ) and Nd(Ⅲ) with 8-hydroxyquinoline in heptane was studied.The results show that the equilibrium constants of praseodymium and neodymium are nearly equal,Kex(Pr3+)=10-11.83,Kex(Nd3+)=10-11.70.The effect of aqueous acidity on the extraction of Pr3+ and Nd3+ with 8-hydroxyquinoline was discussed.The effects of extractant concentraction,different diluents and acetate ion on the extraction reaction were also studied.The results show that acetate ions took part in the extraction reaction in the forms of Pr(Ac-)2+,Nd(Ac-)2+,respectively;with increasing dielectric constant of dilution,the extraction percent decrease and the order is dichloromethane
In this paper,the extraction behaviours of Pr(Ⅲ) and Nd(Ⅲ) from equeous chloride acid medium employing 8-hydroquiloine (HQ) were studied.Equilibrium constant (Kex) in the extraction of Pr(Ⅲ) and Nd(Ⅲ) with 8-hydroxyquinoline in heptane was studied.The results show that the equilibrium constants of praseodymium and neodymium are nearly equal,Kex(Pr3+)=10-11.83,Kex(Nd3+)=10-11.70.The effect of aqueous acidity on the extraction of Pr3+ and Nd3+ with 8-hydroxyquinoline was discussed.The effects of extractant concentraction,different diluents and acetate ion on the extraction reaction were also studied.The results show that acetate ions took part in the extraction reaction in the forms of Pr(Ac-)2+,Nd(Ac-)2+,respectively;with increasing dielectric constant of dilution,the extraction percent decrease and the order is dichloromethane
2008, 25(5): 613-616
Abstract:
Gallium- and aluminum-promoted sulfated zirconia catalysts were prepared by hydrolysis,digestion,wetness impregnation and calcination.The surface acid properties of these catalysts were studied.The high acid value oil was pretreated by esterification on these promoted catalysts.The effects of calcining temperature,molar ratio of methanol to oil were analyzed.The experiment results show that these catalysts exhibit excellent catalytic activities.Under the following conditions:methanol/oil mole ratio 30,amount of catalyst 4%,reaction time 8 h,reaction temperature 67℃,the esterification rate on Ga2O3/SO42-/ZrO2 calicined at 600℃ was the highest and the acid value of oil decreased to 4.1,which had a good effect on producing biodiesel by transesterification in the presence of alkaline catalyst.
Gallium- and aluminum-promoted sulfated zirconia catalysts were prepared by hydrolysis,digestion,wetness impregnation and calcination.The surface acid properties of these catalysts were studied.The high acid value oil was pretreated by esterification on these promoted catalysts.The effects of calcining temperature,molar ratio of methanol to oil were analyzed.The experiment results show that these catalysts exhibit excellent catalytic activities.Under the following conditions:methanol/oil mole ratio 30,amount of catalyst 4%,reaction time 8 h,reaction temperature 67℃,the esterification rate on Ga2O3/SO42-/ZrO2 calicined at 600℃ was the highest and the acid value of oil decreased to 4.1,which had a good effect on producing biodiesel by transesterification in the presence of alkaline catalyst.
2008, 25(5): 617-621
Abstract:
The adsorption behaviors of a new type chitosan crosslinked by aldehyde and epichlorohydrin (abbreviated to AECTS) for Zn2+ were investigated.The effects of temperature,pH of solvent,reaction time and regenerated number on adsorption quantity were studied,and the structure of adsorption products was characterized by Fourier transform IR and XPS.The results showed that the adsorption was realized by binding -NH2 groups in AECTS with Zn2+,the experimental data were satisfied with the Freundlich isotherm adsorption equation,and the adsorption is an endothermic process.The AECTS resin has an excellent adsorption ability for Zn2+and fast adsorption rate.The adsorption quantity can reach 163 mg/g resin even when the initial concentration of Zn2+ is low to 1 g/L at 30℃,which is about 1.7 times that of the saturated absorption of chitosan.However,it was greatly influenced by pH value.The optimum pH value of adsorption of crosslinked chitosan for Zn2+ is 5.0.High adsorption quantity was still maintained when the AECTS resin had been reused for five times after regeneration.
The adsorption behaviors of a new type chitosan crosslinked by aldehyde and epichlorohydrin (abbreviated to AECTS) for Zn2+ were investigated.The effects of temperature,pH of solvent,reaction time and regenerated number on adsorption quantity were studied,and the structure of adsorption products was characterized by Fourier transform IR and XPS.The results showed that the adsorption was realized by binding -NH2 groups in AECTS with Zn2+,the experimental data were satisfied with the Freundlich isotherm adsorption equation,and the adsorption is an endothermic process.The AECTS resin has an excellent adsorption ability for Zn2+and fast adsorption rate.The adsorption quantity can reach 163 mg/g resin even when the initial concentration of Zn2+ is low to 1 g/L at 30℃,which is about 1.7 times that of the saturated absorption of chitosan.However,it was greatly influenced by pH value.The optimum pH value of adsorption of crosslinked chitosan for Zn2+ is 5.0.High adsorption quantity was still maintained when the AECTS resin had been reused for five times after regeneration.
2008, 25(5): 622-625
Abstract:
Oxidation of α-ionone catalyzed by Cu(Ⅱ) acetylacetonate (Cu(acac)2) with molecular oxygen as the oxidant was studied.Various factors were investigated including reaction time,reaction temperature,amount of catalyst,oxygen speed,the types and amounts of solvent by using orthogonal test method.The experiment results indicate that reaction temperature affects the reaction significantly,and the yield of the title product was 40.1% when the reaction was run at 80℃ for 10 h with Cu(acac)2 of a mass fraction of 6% as catalyst at an atmospheric oxygen speed of 50 mL/min with pyridine of a mass fraction of 40% as solvent.The structure of product was characterized by MS,IR,1H NMR and elemental analysis.The catalytic activity of Cu (acac)2 was maintained after repeated use for five times.
Oxidation of α-ionone catalyzed by Cu(Ⅱ) acetylacetonate (Cu(acac)2) with molecular oxygen as the oxidant was studied.Various factors were investigated including reaction time,reaction temperature,amount of catalyst,oxygen speed,the types and amounts of solvent by using orthogonal test method.The experiment results indicate that reaction temperature affects the reaction significantly,and the yield of the title product was 40.1% when the reaction was run at 80℃ for 10 h with Cu(acac)2 of a mass fraction of 6% as catalyst at an atmospheric oxygen speed of 50 mL/min with pyridine of a mass fraction of 40% as solvent.The structure of product was characterized by MS,IR,1H NMR and elemental analysis.The catalytic activity of Cu (acac)2 was maintained after repeated use for five times.
2008, 25(5): 626-628
Abstract:
With thionyl chloride as a chlorination agent,ethyl 4-piperidinecarboxylic acid hydrochloride (Ⅱ) was synthesized by the esterification of 4-piperidinecarboxylic acid (Ⅰ) with ethanol in a yield of 95%,which was reacted with ethyl chloroacetate in acetone to give 1-carbethoxymethyl-4-carbethoxypiperidine (Ⅲ) in a yield of 85%;2-carbethoxy-3-quinuclidinone (Ⅳ) was prepared by the Dieckmann condensation of compound (Ⅲ) under strong basic condition,which was decarboxylated in a yield of 73% under strong-acidic condition,and the total yield was 58%.The product structures was confirmed by IR,1H NMR and MS.
With thionyl chloride as a chlorination agent,ethyl 4-piperidinecarboxylic acid hydrochloride (Ⅱ) was synthesized by the esterification of 4-piperidinecarboxylic acid (Ⅰ) with ethanol in a yield of 95%,which was reacted with ethyl chloroacetate in acetone to give 1-carbethoxymethyl-4-carbethoxypiperidine (Ⅲ) in a yield of 85%;2-carbethoxy-3-quinuclidinone (Ⅳ) was prepared by the Dieckmann condensation of compound (Ⅲ) under strong basic condition,which was decarboxylated in a yield of 73% under strong-acidic condition,and the total yield was 58%.The product structures was confirmed by IR,1H NMR and MS.
