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2014 Volume 31 Issue 6
2014, 31(6): 627-641
doi: 10.3724/SP.J.1095.2014.30378
Abstract:
In recent years,research on trifluoromethylation reactions have been developed rapidly.Since the special chemical and physical properties of the trifluoromethyl group,it plays an increasingly important role in the fields of medicine,pesticides and materials.As the result,a new recognition of radical trifluoromethylation has been achieved along with the development of organofluorine chemistry.This article delivered an overview of the recent progress of radical trifluoromethylation from the perspective of various radical trifluoromethylative precursors as well as reaction mechanisms.
In recent years,research on trifluoromethylation reactions have been developed rapidly.Since the special chemical and physical properties of the trifluoromethyl group,it plays an increasingly important role in the fields of medicine,pesticides and materials.As the result,a new recognition of radical trifluoromethylation has been achieved along with the development of organofluorine chemistry.This article delivered an overview of the recent progress of radical trifluoromethylation from the perspective of various radical trifluoromethylative precursors as well as reaction mechanisms.
2014, 31(6): 642-648
doi: 10.3724/SP.J.1095.2014.30381
Abstract:
Amphiphilic diblock copolymer poly(N-isopropylacrylamide)-b-poly(diacetone acrylamide)(PNIPAM-b-PDAAM),which composed of N-isopropylacrylamide and diacetone acrylamide,was synthesized by reversible addition-fragmentation chain transfer(RAFT) polymerization.Its structure and composition were confirmed by FTIR spectroscopy,1H nuclear magnetic resonance spectroscopy(1H NMR) and gel permeation chromatography(GPC).This copolymer can self-assemble into stable polymeric micelles.The critical micelle concentration values of the self-assembled micelles are about 7.0 mg/L in distilled water relying on fluorescent probe technique.The results measured by dynamic light scattering(DLS) and scanning electron microscopy(SEM) show that the self-assembled PNIPAM-b-PDAAM micelles exhibit spherical core-shell structure with well-defined dispersancy.The mean diameter of micelles estimated by SEM is around 150 nm.The model drug folic acid(FA) was loaded into the micelles as drug carrier material and the in vitro drug release behavior was investigated at body temperature.The results show that the FA-loaded content and the entrapment efficiency reach up to 25% and 72%,respectively.Compared with those at 25℃,in vitro release rates of FA from polymeric micelles in phosphate buffer solution(PBS) at temperatures 37℃,and different pH 4.0,6.86 and 9.18,are all relatively faster within 20 h,and increase with increasing pH value and the largest accumulation release percentage is 31%,67% and 72%,respectively.
Amphiphilic diblock copolymer poly(N-isopropylacrylamide)-b-poly(diacetone acrylamide)(PNIPAM-b-PDAAM),which composed of N-isopropylacrylamide and diacetone acrylamide,was synthesized by reversible addition-fragmentation chain transfer(RAFT) polymerization.Its structure and composition were confirmed by FTIR spectroscopy,1H nuclear magnetic resonance spectroscopy(1H NMR) and gel permeation chromatography(GPC).This copolymer can self-assemble into stable polymeric micelles.The critical micelle concentration values of the self-assembled micelles are about 7.0 mg/L in distilled water relying on fluorescent probe technique.The results measured by dynamic light scattering(DLS) and scanning electron microscopy(SEM) show that the self-assembled PNIPAM-b-PDAAM micelles exhibit spherical core-shell structure with well-defined dispersancy.The mean diameter of micelles estimated by SEM is around 150 nm.The model drug folic acid(FA) was loaded into the micelles as drug carrier material and the in vitro drug release behavior was investigated at body temperature.The results show that the FA-loaded content and the entrapment efficiency reach up to 25% and 72%,respectively.Compared with those at 25℃,in vitro release rates of FA from polymeric micelles in phosphate buffer solution(PBS) at temperatures 37℃,and different pH 4.0,6.86 and 9.18,are all relatively faster within 20 h,and increase with increasing pH value and the largest accumulation release percentage is 31%,67% and 72%,respectively.
2014, 31(6): 649-653
doi: 10.3724/SP.J.1095.2014.30421
Abstract:
Cationic polyvinylpyrrolidone(CPVP) was synthesized by copolymerization of diallyldimethyl ammonium chloride(DADMAC) and vinylpyrrolidone(VP).Polydiallyldimethyl ammonium chloride(PDADMAC) and polyvinylpyrrolidone(PVP) were also synthesized.Their viscosity-average relative molecular masses were measured by viscometry and their structures were characterized by Fourier transform infrared spectroscopy(FTIR).CPVP,PDADMAC and PVP were mixed with ribonucleic acid(RNA) in different ratios in order to measure their loading property.The results indicate that the composite nanoparticles formed by mixing CPVP and RNA with a mass ratio of 2:1 are about 300 nm with a polydistribution index of 0.0966 and the size distribution of nanoparticles is narrower than those of PVP and PDADMAC.
Cationic polyvinylpyrrolidone(CPVP) was synthesized by copolymerization of diallyldimethyl ammonium chloride(DADMAC) and vinylpyrrolidone(VP).Polydiallyldimethyl ammonium chloride(PDADMAC) and polyvinylpyrrolidone(PVP) were also synthesized.Their viscosity-average relative molecular masses were measured by viscometry and their structures were characterized by Fourier transform infrared spectroscopy(FTIR).CPVP,PDADMAC and PVP were mixed with ribonucleic acid(RNA) in different ratios in order to measure their loading property.The results indicate that the composite nanoparticles formed by mixing CPVP and RNA with a mass ratio of 2:1 are about 300 nm with a polydistribution index of 0.0966 and the size distribution of nanoparticles is narrower than those of PVP and PDADMAC.
2014, 31(6): 654-660
doi: 10.3724/SP.J.1095.2014.30420
Abstract:
The effects of chloride donor and aging temperature of neodymium isopropoxide/diisobutylaluminum hydride/chloride donor(Nd(OiPr)3/Al(iBu)2H/RCl) catalyst on isoprene polymerization were investigated.The resulting polymer was fully assessed by NMR,IR and GPC.Chloride donors greatly influenced the relative molecular mass distribution(MWD) of plyisoprene and only Nd(OiPr)3/Al(iBu)2H/Me2SiCl2 catalytic system could afford polyisoprene with a narrow MWD.In the Nd(OiPr)3/Al(iBu)2 H/Me2SiCl2 catalytic system,the polymerization results showed that MWD of polyisoprene kept around 1.5 when the catalyst was aged at 0~50℃ and became much broader(MWD >6.0) when the aging temperature was above 50℃.Additionally,the yield and 1,4-content of polyisopere increased with the aging temperature.
The effects of chloride donor and aging temperature of neodymium isopropoxide/diisobutylaluminum hydride/chloride donor(Nd(OiPr)3/Al(iBu)2H/RCl) catalyst on isoprene polymerization were investigated.The resulting polymer was fully assessed by NMR,IR and GPC.Chloride donors greatly influenced the relative molecular mass distribution(MWD) of plyisoprene and only Nd(OiPr)3/Al(iBu)2H/Me2SiCl2 catalytic system could afford polyisoprene with a narrow MWD.In the Nd(OiPr)3/Al(iBu)2 H/Me2SiCl2 catalytic system,the polymerization results showed that MWD of polyisoprene kept around 1.5 when the catalyst was aged at 0~50℃ and became much broader(MWD >6.0) when the aging temperature was above 50℃.Additionally,the yield and 1,4-content of polyisopere increased with the aging temperature.
2014, 31(6): 661-666
doi: 10.3724/SP.J.1095.2014.30412
Abstract:
The technology to prepare copolymeric resins was described by use of α-pinene(α-P) and 1,3-pentadiene(PD) as monomers and Louis acid as the catalyst.The effect of reaction temperature,reaction time,catalyst concentration,ratio of α-pinene to 1,3-pentadiene on copolymerization was discussed.The optimized reaction condition is as follows:reaction temperature 15℃,reaction time 2 h,solvent toluene,m(catalyst):m(α-P and PD)=1%,n(α-P):n(PD)=1:2.The product yield,softening point,Chroma,Mn,and relative molecular mass distribution(MWD) are 72.5%,121.3℃,4,1549,and 1.92,respectively.The product has good thermal stability and adhesion compatibility.
The technology to prepare copolymeric resins was described by use of α-pinene(α-P) and 1,3-pentadiene(PD) as monomers and Louis acid as the catalyst.The effect of reaction temperature,reaction time,catalyst concentration,ratio of α-pinene to 1,3-pentadiene on copolymerization was discussed.The optimized reaction condition is as follows:reaction temperature 15℃,reaction time 2 h,solvent toluene,m(catalyst):m(α-P and PD)=1%,n(α-P):n(PD)=1:2.The product yield,softening point,Chroma,Mn,and relative molecular mass distribution(MWD) are 72.5%,121.3℃,4,1549,and 1.92,respectively.The product has good thermal stability and adhesion compatibility.
2014, 31(6): 667-671
doi: 10.3724/SP.J.1095.2014.30424
Abstract:
The phosphorus-containing diamine compound,bis(3-aminophenyl) phenyl phosphine oxide(DAPPO),was synthesized with cheap triphenylphosphine oxide and nitro-sulfuric acid.The phosphoruscontaining polyimide(PI) fibers were prepared by introducing DAPPO into the polymer backbone of 4,4'-oxydianiline(ODA),pyromellitic dianhydride(PMDA) and 3,3',4,4'-biphenyl tertracarboxylic dianhydride(BPDA).The results of thermogravimetric analysis indicate that thermal stability of the PI fibers is obviously enhanced with increasing phosphorus content.When n(DAPPO):n(ODA) is 7:93,the value of limiting oxygen index of the fiber has reached 43.These powerfully demonstrate that the flame retardant of PI fibers has been significantly enhanced.
The phosphorus-containing diamine compound,bis(3-aminophenyl) phenyl phosphine oxide(DAPPO),was synthesized with cheap triphenylphosphine oxide and nitro-sulfuric acid.The phosphoruscontaining polyimide(PI) fibers were prepared by introducing DAPPO into the polymer backbone of 4,4'-oxydianiline(ODA),pyromellitic dianhydride(PMDA) and 3,3',4,4'-biphenyl tertracarboxylic dianhydride(BPDA).The results of thermogravimetric analysis indicate that thermal stability of the PI fibers is obviously enhanced with increasing phosphorus content.When n(DAPPO):n(ODA) is 7:93,the value of limiting oxygen index of the fiber has reached 43.These powerfully demonstrate that the flame retardant of PI fibers has been significantly enhanced.
2014, 31(6): 672-677
doi: 10.3724/SP.J.1095.2014.30438
Abstract:
The effect of the rlative molecular mass of poly(ethylene oxide) on the phase behavior of its mixture with charge stabilized poly(methyl methacrylate) colloidal dispersion was investigated by means of synchrotron small-angle X-ray scattering technique.The phase structure of the mixture is generally determined by the volume fraction of the colloidal dispersion and the concentration of the polymer.At a certain volume fraction of colloidal dispersion,the mixtures present a homogeneous state when the polymer concentration is below a critical value.When the polymer concentration is larger than the critical concentration,sedimentation can be observed.The mixtures are in a cluster phase or a crystalline state with a face-centered cubic structure.The relative molecular mass of poly(ethylene oxide) also plays an important role in the phase behavior of the mixture.Our results show that the critical concentration of the polymer is low for the mixtures with the polymer of high relative molecular mass.The relative molecular mass of the polymer also affects the formation of crystals.
The effect of the rlative molecular mass of poly(ethylene oxide) on the phase behavior of its mixture with charge stabilized poly(methyl methacrylate) colloidal dispersion was investigated by means of synchrotron small-angle X-ray scattering technique.The phase structure of the mixture is generally determined by the volume fraction of the colloidal dispersion and the concentration of the polymer.At a certain volume fraction of colloidal dispersion,the mixtures present a homogeneous state when the polymer concentration is below a critical value.When the polymer concentration is larger than the critical concentration,sedimentation can be observed.The mixtures are in a cluster phase or a crystalline state with a face-centered cubic structure.The relative molecular mass of poly(ethylene oxide) also plays an important role in the phase behavior of the mixture.Our results show that the critical concentration of the polymer is low for the mixtures with the polymer of high relative molecular mass.The relative molecular mass of the polymer also affects the formation of crystals.
2014, 31(6): 678-683
doi: 10.3724/SP.J.1095.2014.30426
Abstract:
Zein microspheres with the most probable diameter of 40 nm were prepared by phase separation process.Zein colloidal dispersion was concentrated under reduced pressure by rotary evaporation.Zein colloid with obvious Tyndall effect is stable even after preparation for a few months.The zeta-potentials of zein colloid were determined by electrophoretic mobility measurements.The results show that zein colloid has excellent dispersing property at pH around 4.Pickering emulsions of oil-in-water type were prepared by using zein microspheres as stabilizers.The effects of the amount of colloidal particles,oil/water volume ratio on emulsion stability were investigated.The results indicate that the addition of zein colloidal particles at 0.4% and the higher oil/water volume ratio in Pickering emulsion are propitious to increase the emulsion stability.The stability mechanism of zein microspheres as stabilizers in Pickering emulsion was also discussed on account of its amphiphilic macromolecules and interfacial assembly.
Zein microspheres with the most probable diameter of 40 nm were prepared by phase separation process.Zein colloidal dispersion was concentrated under reduced pressure by rotary evaporation.Zein colloid with obvious Tyndall effect is stable even after preparation for a few months.The zeta-potentials of zein colloid were determined by electrophoretic mobility measurements.The results show that zein colloid has excellent dispersing property at pH around 4.Pickering emulsions of oil-in-water type were prepared by using zein microspheres as stabilizers.The effects of the amount of colloidal particles,oil/water volume ratio on emulsion stability were investigated.The results indicate that the addition of zein colloidal particles at 0.4% and the higher oil/water volume ratio in Pickering emulsion are propitious to increase the emulsion stability.The stability mechanism of zein microspheres as stabilizers in Pickering emulsion was also discussed on account of its amphiphilic macromolecules and interfacial assembly.
2014, 31(6): 684-689
doi: 10.3724/SP.J.1095.2014.30395
Abstract:
With triphenylamine as the core and the second generation oligocarbazole as the dendron,a dendritic host,namely H2A,has been designed and synthesized.H2A shows good film-forming properties and excellent thermal ability(Tg=351℃) and its triplet energy is 2.84 eV.When using H2A as the host for IrⅢ bis(4,6-difluorophenylpyridinato) picolate(FIrpic),blue-emitting electrophosphorescent devices reveal a turn-on voltage of 4.8 V,and a power efficiency of 7.0 lm/W.The performance is superior to that of 4,4',4"-tris(N-carbazoyl) triphenylamine(TCTA),which shows a turn-on voltage and power efficiency of 6.0 V and 6.1 lm/W,respectively.
With triphenylamine as the core and the second generation oligocarbazole as the dendron,a dendritic host,namely H2A,has been designed and synthesized.H2A shows good film-forming properties and excellent thermal ability(Tg=351℃) and its triplet energy is 2.84 eV.When using H2A as the host for IrⅢ bis(4,6-difluorophenylpyridinato) picolate(FIrpic),blue-emitting electrophosphorescent devices reveal a turn-on voltage of 4.8 V,and a power efficiency of 7.0 lm/W.The performance is superior to that of 4,4',4"-tris(N-carbazoyl) triphenylamine(TCTA),which shows a turn-on voltage and power efficiency of 6.0 V and 6.1 lm/W,respectively.
2014, 31(6): 690-695
doi: 10.3724/SP.J.1095.2014.30382
Abstract:
A blue phosphorescent iridium(Ⅲ) complex incorporating 2',6'-difluoro-2,3'-bipyridine and acetyl acetonate,(dfpypy)2Ir(acac),was synthesized.At room temperature,(dfpypy)2Ir(acac) in tetrahydrofuran was intensely phosphorescent with the maximum emission wavelength(λmax) at 465 nm accompanied a shoulder peak at 490 nm.The full-width at half maximum(fwhm) was 53 nm.The emission bands at 465 and 490 nm were red-shifted,compared with the emission spectra of fac-Ir(dfpypy)3 which has two emission peaks at 438 and 463 nm with nearly equal intensities.The photoluminescence(PL) quantum yield in degassed tetrahydrofuran solution at room temperature was determined to be 0.41.The blue phosphorescent electroluminescence devices were fabricated by doping(dfpypy)2Ir(acac) into the PVK host.The device has the following configuration:ITO/PEDOT/PVK:(dfpypy)2Ir(acac)(100:x)(70 nm)/Ba/Al,ITO:indium tin oxide,PEDOT:poly(3,4-ethylenedioxythiophene),PSS:poly(styrene sulfonic acid),PVK:poly(vinylcarbazole),x:doping contents.The doping concentration of(dfpypy)2Ir(acac) varied from 2% to 12%.The sky blue emission was observed for all doping concentrations.When the host in devices was doped with 2% of(dfpypy)2 Ir(acac),the maximum luminance efficiency of 1.6 cd/A at a current density of 0.23×10-3 A/cm2 was achieved and the maximum brightness of 1400 cd/m2 at driven voltage of 15.4 V with 1931 Commission Internationale L'Eclairage(CIE) coordinates of(0.15,0.27).
A blue phosphorescent iridium(Ⅲ) complex incorporating 2',6'-difluoro-2,3'-bipyridine and acetyl acetonate,(dfpypy)2Ir(acac),was synthesized.At room temperature,(dfpypy)2Ir(acac) in tetrahydrofuran was intensely phosphorescent with the maximum emission wavelength(λmax) at 465 nm accompanied a shoulder peak at 490 nm.The full-width at half maximum(fwhm) was 53 nm.The emission bands at 465 and 490 nm were red-shifted,compared with the emission spectra of fac-Ir(dfpypy)3 which has two emission peaks at 438 and 463 nm with nearly equal intensities.The photoluminescence(PL) quantum yield in degassed tetrahydrofuran solution at room temperature was determined to be 0.41.The blue phosphorescent electroluminescence devices were fabricated by doping(dfpypy)2Ir(acac) into the PVK host.The device has the following configuration:ITO/PEDOT/PVK:(dfpypy)2Ir(acac)(100:x)(70 nm)/Ba/Al,ITO:indium tin oxide,PEDOT:poly(3,4-ethylenedioxythiophene),PSS:poly(styrene sulfonic acid),PVK:poly(vinylcarbazole),x:doping contents.The doping concentration of(dfpypy)2Ir(acac) varied from 2% to 12%.The sky blue emission was observed for all doping concentrations.When the host in devices was doped with 2% of(dfpypy)2 Ir(acac),the maximum luminance efficiency of 1.6 cd/A at a current density of 0.23×10-3 A/cm2 was achieved and the maximum brightness of 1400 cd/m2 at driven voltage of 15.4 V with 1931 Commission Internationale L'Eclairage(CIE) coordinates of(0.15,0.27).
2014, 31(6): 696-701
doi: 10.3724/SP.J.1095.2014.30406
Abstract:
The design,synthesis,and structural characterization of a novel bisindolinospiropyran(1) was reported.The acidichromic and ionochromic properties of compound 1 were investigated.The results indicate that compound 1 possesses an interesting ring opening reaction with the addition of proton or several metal ions in isopropanol.Upon addition of hydrogen or metal ions(Fe3+,Al3+ and Cu2+),compound 1 shows a new absorption spectra peak around 460 nm,and the color of the solution changes from colorless to red.The color and absorption spectra of this compound can be restored when the hydroxide ions or EDTA is added.These properties can be applied to molecular sensors and ion recognition.
The design,synthesis,and structural characterization of a novel bisindolinospiropyran(1) was reported.The acidichromic and ionochromic properties of compound 1 were investigated.The results indicate that compound 1 possesses an interesting ring opening reaction with the addition of proton or several metal ions in isopropanol.Upon addition of hydrogen or metal ions(Fe3+,Al3+ and Cu2+),compound 1 shows a new absorption spectra peak around 460 nm,and the color of the solution changes from colorless to red.The color and absorption spectra of this compound can be restored when the hydroxide ions or EDTA is added.These properties can be applied to molecular sensors and ion recognition.
2014, 31(6): 702-706
doi: 10.3724/SP.J.1095.2014.30428
Abstract:
3-(4-Benzylpiperazin-1-ylmethyl) pyrazolo[1,5-α]pyridine,3-[4-(4-chlorobenzyl) piperazin-1-ylmethyl]pyrazolo[1,5-α]pyridine and 3-[4-(4-methoxybenzyl) piperazin-1-ylmethyl]pyrazolo[1,5-a]pyridine were synthesized from pyrazolo[1,5-α]pyridine-3-carbaldehyde and 1-piperazinearboxaldehyde through reductive amination,amide hydrolysis and N-alkylation.The structures of the intermediates and the target compounds were confirmed by 1H NMR and ESI MS.Through in vitro receptor binding assay,the affinity constants(Ki) of the target compounds were determined to be 1.6,7.2,65 nmol/L for D4 receptor;1920,5320,9800 nmol/L for D2 receptor;1710,4270 and 5600 nmol/L for dopamine D3 receptor,respectively.The results suggested that 3-(4-benzylpiperazin-1-ylmethyl) pyrazolo[1,5-α]pyridine is a potential dopamine D4 receptor ligand.
3-(4-Benzylpiperazin-1-ylmethyl) pyrazolo[1,5-α]pyridine,3-[4-(4-chlorobenzyl) piperazin-1-ylmethyl]pyrazolo[1,5-α]pyridine and 3-[4-(4-methoxybenzyl) piperazin-1-ylmethyl]pyrazolo[1,5-a]pyridine were synthesized from pyrazolo[1,5-α]pyridine-3-carbaldehyde and 1-piperazinearboxaldehyde through reductive amination,amide hydrolysis and N-alkylation.The structures of the intermediates and the target compounds were confirmed by 1H NMR and ESI MS.Through in vitro receptor binding assay,the affinity constants(Ki) of the target compounds were determined to be 1.6,7.2,65 nmol/L for D4 receptor;1920,5320,9800 nmol/L for D2 receptor;1710,4270 and 5600 nmol/L for dopamine D3 receptor,respectively.The results suggested that 3-(4-benzylpiperazin-1-ylmethyl) pyrazolo[1,5-α]pyridine is a potential dopamine D4 receptor ligand.
2014, 31(6): 707-714
doi: 10.3724/SP.J.1095.2014.30439
Abstract:
One novel iron complex,[Fe(H2L)2]·(CH3COO)2·(OH)·H2O(H2L=2,6-di-(5-methyl-1H-pyrazol-3-yl) pyridine) with N-donor ligand 2,6-di-(5-methyl-1H-pyrazol-3-yl) pyridine,was synthesized and characterized by elemental analysis,powder X-ray diffraction(PXRD) and single-crystal X-ray diffraction.In addition,the catalytic activity of the complex to cyclohexane oxidation was examined.The effects of various reaction factors such as the amount of H2O2,HNO3 and water,reaction time,as well as the temperature on the formation and decomposition of cyclohexylhydroperoxide,and the yield of C6H10O and C6H11OH were evaluated.The mechanism of oxidation reaction was also discussed.It shows that H2O2 is the main oxidant for the oxidation of cyclohexane to C6H11OOH catalyzed by the titled Fe complex;HNO3 has no oxidizing effect on this process,but can accelerate the formation and decomposition rates of C6H11OOH.Water has an inhibition effect on the catalytic activity,thereby lowering the formation and decomposition rates of C6H11OOH.The formation rates of C6H11OOH and C6H10O(C6H11OH) are different at different reaction stages.Higher temperature can promote the decomposition of C6H11OOH,which benefits the formation of C6H10O and C6H11OH.
One novel iron complex,[Fe(H2L)2]·(CH3COO)2·(OH)·H2O(H2L=2,6-di-(5-methyl-1H-pyrazol-3-yl) pyridine) with N-donor ligand 2,6-di-(5-methyl-1H-pyrazol-3-yl) pyridine,was synthesized and characterized by elemental analysis,powder X-ray diffraction(PXRD) and single-crystal X-ray diffraction.In addition,the catalytic activity of the complex to cyclohexane oxidation was examined.The effects of various reaction factors such as the amount of H2O2,HNO3 and water,reaction time,as well as the temperature on the formation and decomposition of cyclohexylhydroperoxide,and the yield of C6H10O and C6H11OH were evaluated.The mechanism of oxidation reaction was also discussed.It shows that H2O2 is the main oxidant for the oxidation of cyclohexane to C6H11OOH catalyzed by the titled Fe complex;HNO3 has no oxidizing effect on this process,but can accelerate the formation and decomposition rates of C6H11OOH.Water has an inhibition effect on the catalytic activity,thereby lowering the formation and decomposition rates of C6H11OOH.The formation rates of C6H11OOH and C6H10O(C6H11OH) are different at different reaction stages.Higher temperature can promote the decomposition of C6H11OOH,which benefits the formation of C6H10O and C6H11OH.
2014, 31(6): 715-720
doi: 10.3724/SP.J.1095.2014.30401
Abstract:
A novel polystyrene-supported ferric chloride catalyst was prepared and characterized by IR,XRD and SEM.The catalyst exhibited excellent catalytic activities for the synthesis of β-amino ketone derivatives via one-pot Mannich reaction from acetophenone,aromatic aldehydes and aromatic amines.The catalyst could be recycled easily and the activity of the catalyst maintained after 4 cycles.
A novel polystyrene-supported ferric chloride catalyst was prepared and characterized by IR,XRD and SEM.The catalyst exhibited excellent catalytic activities for the synthesis of β-amino ketone derivatives via one-pot Mannich reaction from acetophenone,aromatic aldehydes and aromatic amines.The catalyst could be recycled easily and the activity of the catalyst maintained after 4 cycles.
2014, 31(6): 721-725
doi: 10.3724/SP.J.1095.2014.30357
Abstract:
A novel protocol,efficient,inexpensive for the microwave-assisted copper-catalyzed synthesis of benzothiazoles derivatives through the reaction of 2-iodoanilines with aldehydes and KSCN in aqueous solution was investigated.The reactions was catalyzed by a combination of CuI and 1,10-phenanthroline with Cs2CO3 as a base and in neat water at 100℃ for 30 min.A variety of benzothiazoles can be synthesized in an excellent yield up to 94%.
A novel protocol,efficient,inexpensive for the microwave-assisted copper-catalyzed synthesis of benzothiazoles derivatives through the reaction of 2-iodoanilines with aldehydes and KSCN in aqueous solution was investigated.The reactions was catalyzed by a combination of CuI and 1,10-phenanthroline with Cs2CO3 as a base and in neat water at 100℃ for 30 min.A variety of benzothiazoles can be synthesized in an excellent yield up to 94%.
2014, 31(6): 726-731
doi: 10.3724/SP.J.1095.2014.30450
Abstract:
Rice straw was extracted with petroleum ether and ethanol by Soxhlet extraction,respectively.Detailed characterizations of the extracts were performed with a gas chromatography/mass spectrometer(GC/MS),Fourier transform infrared(FTIR) spectrometer.The results show that the extraction yields of ethanol and petroleum ether are 8% and 6%,respectively.In total,40 organic species were identified from extracts,and they can be classified into 7 groups of components:alcohols and phenols(APs),aldehydes,ketones,acids,esters,hydrocarbons(HCs) and organonitrogen compounds(ONs).Esters,HCs and APs are the most abundant compounds in the petroleum ether extactable fraction,the total relative content of which is 91.7%.More HCs,acids,esters,and APs are detected in ethanol extracts,the total relative content is 83.9%.The research is significant in the high value added utilization of straw.
Rice straw was extracted with petroleum ether and ethanol by Soxhlet extraction,respectively.Detailed characterizations of the extracts were performed with a gas chromatography/mass spectrometer(GC/MS),Fourier transform infrared(FTIR) spectrometer.The results show that the extraction yields of ethanol and petroleum ether are 8% and 6%,respectively.In total,40 organic species were identified from extracts,and they can be classified into 7 groups of components:alcohols and phenols(APs),aldehydes,ketones,acids,esters,hydrocarbons(HCs) and organonitrogen compounds(ONs).Esters,HCs and APs are the most abundant compounds in the petroleum ether extactable fraction,the total relative content of which is 91.7%.More HCs,acids,esters,and APs are detected in ethanol extracts,the total relative content is 83.9%.The research is significant in the high value added utilization of straw.
2014, 31(6): 732-736
doi: 10.3724/SP.J.1095.2014.30360
Abstract:
Effects of 2-phosphonobutane-1,2,4-tricarboxylic acid(PBTCA) and N-(2-hydroxypropyl) methacrylamide(HPMA) inhibitors on the sodium(potassium) fluorosilicate crystallization were studied by turbidity and static methods.Mechanism of inhibition was explained according to classic nucleation theory.Morphology and crystal form of sodium(potassium) fluorosilicate were characterized by SEM and XRD.The results show that PBTCA and HPMA can inhibit crystallization precipitation by improving the surface free energy of sodium(potassium) fluorosilicate.The mixture of PBTCA and HPMA has distinct synergy,which can improve surface free energy of Na2SiF6 from 108 mJ/m2 to 126 mJ/m2,inhibition rate of Na+ from 6.2% to 70.3%,surface free energy of K2SiF6 from 199 mJ/m2 to 230 mJ/m2 and inhibition rate of K+ from 10.2% to 45.3%,respectively.Particles of sodium(potassium) fluorosilicate are dispersed and diminished in the presence of PBTCA and HPMA.The crystal form is mainly NaKSiF6 in the blank solution,while they are mainly Na2SiF6 and K2SiF6 in the presence of PBTCA and HPMA.
Effects of 2-phosphonobutane-1,2,4-tricarboxylic acid(PBTCA) and N-(2-hydroxypropyl) methacrylamide(HPMA) inhibitors on the sodium(potassium) fluorosilicate crystallization were studied by turbidity and static methods.Mechanism of inhibition was explained according to classic nucleation theory.Morphology and crystal form of sodium(potassium) fluorosilicate were characterized by SEM and XRD.The results show that PBTCA and HPMA can inhibit crystallization precipitation by improving the surface free energy of sodium(potassium) fluorosilicate.The mixture of PBTCA and HPMA has distinct synergy,which can improve surface free energy of Na2SiF6 from 108 mJ/m2 to 126 mJ/m2,inhibition rate of Na+ from 6.2% to 70.3%,surface free energy of K2SiF6 from 199 mJ/m2 to 230 mJ/m2 and inhibition rate of K+ from 10.2% to 45.3%,respectively.Particles of sodium(potassium) fluorosilicate are dispersed and diminished in the presence of PBTCA and HPMA.The crystal form is mainly NaKSiF6 in the blank solution,while they are mainly Na2SiF6 and K2SiF6 in the presence of PBTCA and HPMA.
2014, 31(6): 737-741
doi: 10.3724/SP.J.1095.2014.30387
Abstract:
A method was established for the analysis of gatifloxacin or fleroxacin in water sample by ultrasonic assisted hydrophobic ionic liquid(1-hexyl-3-methylimidazolium hexafluorophosphate,[C6mim][PF6]) liquid-phase microextraction coupled with high performance liquid chromatography(HPLC).The pH value of solution,amount of ionic liquid and other factors which might affect the extraction efficiency were researched.To gatifloxacin water sample at pH=3.3 and fleroxacin water sample at pH=2.1 was added 0.4 mL of[C6mim][PF6],respectively,for ultrasonic extraction.After extraction,phase separation was performed by centrifugation.The sediment phase were injected into the HPLC system for analysis.By this method,the linear ranges for analysis are 0.5~100 μg/L and the relative standard deviations(n=5) for them are 2.80 and 5.93,respectively.The limits of detection(3S/N) for gatifloxacin and fleroxacin are 0.46 and 0.97 μg/L,respectively.Under the above mentioned conditions,the extraction recoveries for gatifloxacin or fleroxacin water samples were found to be 80.5%~89.5% and 93.3%~99.0%,respectively.
A method was established for the analysis of gatifloxacin or fleroxacin in water sample by ultrasonic assisted hydrophobic ionic liquid(1-hexyl-3-methylimidazolium hexafluorophosphate,[C6mim][PF6]) liquid-phase microextraction coupled with high performance liquid chromatography(HPLC).The pH value of solution,amount of ionic liquid and other factors which might affect the extraction efficiency were researched.To gatifloxacin water sample at pH=3.3 and fleroxacin water sample at pH=2.1 was added 0.4 mL of[C6mim][PF6],respectively,for ultrasonic extraction.After extraction,phase separation was performed by centrifugation.The sediment phase were injected into the HPLC system for analysis.By this method,the linear ranges for analysis are 0.5~100 μg/L and the relative standard deviations(n=5) for them are 2.80 and 5.93,respectively.The limits of detection(3S/N) for gatifloxacin and fleroxacin are 0.46 and 0.97 μg/L,respectively.Under the above mentioned conditions,the extraction recoveries for gatifloxacin or fleroxacin water samples were found to be 80.5%~89.5% and 93.3%~99.0%,respectively.
2014, 31(6): 742-748
doi: 10.3724/SP.J.1095.2014.30416
Abstract:
A label-free electrochemical aptasensor has been constructed for the electrochemical detection of thrombin.Two layers of nickel hexacyanoferrate redox probes sandwiched with multi-walled carbon nanotubes for the sensitivity enhancement were directly immobilized on the electrode surface by electrodeposition,and gold nanoparticles was used as the immobilization matrix for the aptamers.SEM was used to characterize the morphologies of multi-walled carbon nanotubes and nickel hexacyanoferrate.Electrochemical impedance spectroscopy was used to monitor the self-assembly process of aptamer biosensors.Electrochemical behaviors of aptamer biosensors were studied by cyclic voltammetry and differential pulse voltammetry.The biosensor shows a good linear range of 1.0 ng/L~1.0 mg/L(R=0.998) for the electrochemical detection of thrombin with a detection limit of 0.2 ng/L(S/N=3).
A label-free electrochemical aptasensor has been constructed for the electrochemical detection of thrombin.Two layers of nickel hexacyanoferrate redox probes sandwiched with multi-walled carbon nanotubes for the sensitivity enhancement were directly immobilized on the electrode surface by electrodeposition,and gold nanoparticles was used as the immobilization matrix for the aptamers.SEM was used to characterize the morphologies of multi-walled carbon nanotubes and nickel hexacyanoferrate.Electrochemical impedance spectroscopy was used to monitor the self-assembly process of aptamer biosensors.Electrochemical behaviors of aptamer biosensors were studied by cyclic voltammetry and differential pulse voltammetry.The biosensor shows a good linear range of 1.0 ng/L~1.0 mg/L(R=0.998) for the electrochemical detection of thrombin with a detection limit of 0.2 ng/L(S/N=3).
