The effects of potassium ferricyanide,sodium n-dodecyl sulfate,sodium hydroxide and temperature on the molecular weight and the yield of poly(2,6-dimethyl-1,4-phenylene oxide)(PPO) synthesized in an aqueous medium wer...The effects of potassium ferricyanide,sodium n-dodecyl sulfate,sodium hydroxide and temperature on the molecular weight and the yield of poly(2,6-dimethyl-1,4-phenylene oxide)(PPO) synthesized in an aqueous medium were studied.It was found that oxygen in air had little influence on the oxidative polymerization of 2,6-dimethylphenol(DMP) in the aqueous medium,and potassium ferricyanide was only an oxidant during the oxidative polymerization of DMP.Sodium n-dodecyl sulfate could stabilize polymer particles an...展开更多
Electroanalytical techniques could be a reliable and promising alternative to classical and sophisticated methods because of their simplicity（small and portable）,easy use,the ability to deliver fast response with hi...Electroanalytical techniques could be a reliable and promising alternative to classical and sophisticated methods because of their simplicity（small and portable）,easy use,the ability to deliver fast response with high sensitivity and selectivity.A square wave voltammetric method was developed for the assessment of organophosphorus（OPs） compound impact on acetylcholinesterase（AChE） of Pheretima with 2,6-dimethyl-p-benzoquinone（2,6DMBQ） as a redox indicator.The substrate of acetylthiocholine is hydrolyzed by AChE and the produced thiocholine reacts with 2,6-DMBQ to give an obvious shift of electrochemical signal.The reduction peak of 2,6-DMBQ is located at around 0.18 V which is far away from the oxidation potential of possible interference components often present in biosample.The decreased rate of reduction current was related with the activity of AChE.The inhibition of parathion-methyl on AChE was assessed.The inhibiton rate of OPs on AChE activity increased quickly during the first 10 min inhibition,and after that the value of inhibition rate approached to be constant.AChE lost almost 29.3% of activity after 10 min incubation with 1 μg/mL parathion-methyl and 67.5% of activity with 10 μg/mL parathion-methyl,while the activity that corresponds to 40 μg/mL parathion-methyl was nearly completely inhibited（94.9%）.Compared to cyclic voltammetry and amperometry,Square wave voltammetry（SWV） method is a high sensitive electroanalysis with fast scan-rate（only several seconds for one signal value） which is useful to prevent the electrodes from possible fouling or passivation.This method can be employed to assess the inhibition of organophosphate on AChE and investigate OPs impact on environmental animals.展开更多
Eight rare earth metal （ Ⅲ ） complexes with 2- （ （（4,6-dimethyl）-2-pyrimidinyl） thio）-acetic acid, LnL3· n H2O [HL = 2-（（（4,6-dimethyl）-2-pyrimidinyl）thio）-acetic acid; Ln = La, Ce, Pr, Nd, Sm Eu, ...Eight rare earth metal （ Ⅲ ） complexes with 2- （ （（4,6-dimethyl）-2-pyrimidinyl） thio）-acetic acid, LnL3· n H2O [HL = 2-（（（4,6-dimethyl）-2-pyrimidinyl）thio）-acetic acid; Ln = La, Ce, Pr, Nd, Sm Eu, Gd, Tb; n = 4 or 5], were prepared and characterized by elemental analysis, complexometric titration, thermal analysis, conductivity, IR and ^1H- NMR. The results reveal that carboxyl group of the hgand coordinates with rare earth ions in bidentate mode after deprotonated. The water molecules exist as crystal water in the complexes. The anti-tumour activities of HL and some complexes were tested by both the MTT and SRB methods. The results show that the suppression ratios of some complexes against the tested tumour cells （HL-60 human leukemia cell lines, BGC-823 human gastric carcinoma cell lines, hela human cervix adenocarcinoma cell lines and Bel-7402 human hepatic carcinoma cell lines） are superior to HL.展开更多
In the presence of diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate（DHP） and a catalytic amount of potassium iodide,severalα-halo ketones were easily reduced to the corresponding ketones in acetone media....In the presence of diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate（DHP） and a catalytic amount of potassium iodide,severalα-halo ketones were easily reduced to the corresponding ketones in acetone media.The procedure presented here showed several merits such as short reaction time,practical experimental and isolated procedure,and excellent yields of products.展开更多
The facile and efficient total syntheses of monoterpenoid acid 7a and its ester 7b, isolated from Artemisia siebert and Piper aduncum respectively, can be completed in four steps with an overall yield 41%.
2,6-Dimethylnaphthalene (2,6-DMN) is a key intermediate for polyethylene naphthalate synthesis. The selective synthesis of 2,6-DMN from naphthalene and methanol was carried out over different zeolites (HZSM-5, Hβ, HU...2,6-Dimethylnaphthalene (2,6-DMN) is a key intermediate for polyethylene naphthalate synthesis. The selective synthesis of 2,6-DMN from naphthalene and methanol was carried out over different zeolites (HZSM-5, Hβ, HUSY and SAPO-11) modified by 0.1wt% PdO under atmospheric pressure. Among the adopted zeolites, SAPO-11 exhibits exceptional shape-selectivity and stability to synthesize 2,6-dimethylnaphthalene from methylation of naphthalene, due to the special pore structure of SAPO-11 which inosculated better with 2,6-dimethylnaphthalene than with 2,7-dimethylnaphthalene.展开更多
A new metal-organic coordination polymer [Zn2（trz）2（mpda）（H2O）]n（1, trz = 1,2,4-triazole, H2 mpda = 2,6-dimethylpyridine-3,5-dicarboxylic acid） was synthesized and characterized by single-crystal X-ray analyse...A new metal-organic coordination polymer [Zn2（trz）2（mpda）（H2O）]n（1, trz = 1,2,4-triazole, H2 mpda = 2,6-dimethylpyridine-3,5-dicarboxylic acid） was synthesized and characterized by single-crystal X-ray analyses. The crystal is of monoclinic system, space group P21/n, a = 9.619（3）, b = 8.920（3）, c = 22.159（6）, β = 96.897（4）°, V = 1887.3（9）3, Z = 4, Mr = 478.04, D3 c = 1.682 Mg/m, F（000） = 960, the final R = 0.0264 and wR = 0.0870（I 2σ（I））. Compound 1 consists of {[Zn4（trz）4]4＋}n layers, which are further connected by mpda2- to complete a three-dimensional structure. The title compound exhibits luminescence at λmax = 415 nm upon excitation at 364 nm.展开更多
A highly selective synthesis of 2,6-dimethylnaphthanlene（2,6-DMN） by transalkylation between 2-methylnaphthanlene（2-MN） and 1,2,4,5-tetramethylbenzene（TeMB） was performed with 1-alkyl-3-methylimidazo- lium alumi...A highly selective synthesis of 2,6-dimethylnaphthanlene（2,6-DMN） by transalkylation between 2-methylnaphthanlene（2-MN） and 1,2,4,5-tetramethylbenzene（TeMB） was performed with 1-alkyl-3-methylimidazo- lium aluminum chloride（[Cnmim]Cl-AlCl3） ionic liquids（ILs） as catalysts. The influences of the alkyl group as the organic cation, the acidic strength of [C4mim]Cl-AlCl3 ILs as well as the reaction conditions on the catalytic performance were investigated. [C4mim]Cl-AlCl3 ILs[x（AlCl3）=71%] exhibited high activity and selectivity toward 2,6-DMN. The selectivity to 2,6-DMN and the 2,6-DMN/2,7-DMN ratio reached up to 68.2% and 3.7：1, respectively. The UV-Vis spectrum of TeMB treated by different ILs shows that the protonated degree of TeMB dependeds on the acidity strength of ILs, which has a significant impact on the reaction results. The high protonated degree of TeMB is advantageous to enhancing the conversion of transalkylation and the large stereo-hindrance effect of TeMB is favorable to improving the selecivity to 2,6-DMN.展开更多
Two new complexes, [Cu（DMB）2（NAA）2]（1） and [Co（DMB）2（NAA）2]（2）（DMB = 5,6-dimethylbenzimidazole, HNNA = 1-naphthylacetic acid）, were hydrothermally synthesized and characterized by elemental analysis, IR ...Two new complexes, [Cu（DMB）2（NAA）2]（1） and [Co（DMB）2（NAA）2]（2）（DMB = 5,6-dimethylbenzimidazole, HNNA = 1-naphthylacetic acid）, were hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy, TGA, PXRD and single-crystal X-ray diffraction analysis. The coordination geometry of the metal centers is a perfect square plane for 1 and a distorted tetrahedron for 2. In compound 1, the mononuclear units are linked by N–H···O hydrogen bonds to form a 1D chain structure, while mononuclear motifs of 2 are extended via N–H···O hydrogen bonding and π-π stacking interactions into a 2D supramolecular layer. The remarkable catalytic properties of the two complexes for the degradation of Congo red dye have been found.展开更多
A charge transfer hydrogen bonded complex between the electron donor (proton acceptor) 2-amino-4,6-dimethylpyridine with the electron acceptor (proton donor) chloranilic acid has been synthesized and studied experimen...A charge transfer hydrogen bonded complex between the electron donor (proton acceptor) 2-amino-4,6-dimethylpyridine with the electron acceptor (proton donor) chloranilic acid has been synthesized and studied experimentally and theoretically. The stability constant recorded high values indicating the high stability of the formed complex. In chloroform, ethanol, methanol and acetonitrile were found the stoichiometric ratio 1:1. The solid complex was prepared and characterized by different spectroscopy techniques. FTIR, 1H and 13C NMR studies supported the presence of proton and charge transfers in the formed complex. Complemented with experimental results, molecular modelling using the density functional theory (DFT) calculations was carried out in the gas, chloroform and methanol phases where the existence of charge and hydrogen transfers. Finally, a good consistency between experimental and theoretical calculations was found confirming that the applied basis set is the suitable one for the system under investigation.展开更多
基金supported by the National Natural Science Foundation of China(No.20674075)Natural ScienceFoundation of Zhejiang Province(No.Y404299)Young Talents Project of Zhejiang Province(No.2008R40G2010065).
文摘The effects of potassium ferricyanide,sodium n-dodecyl sulfate,sodium hydroxide and temperature on the molecular weight and the yield of poly(2,6-dimethyl-1,4-phenylene oxide)(PPO) synthesized in an aqueous medium were studied.It was found that oxygen in air had little influence on the oxidative polymerization of 2,6-dimethylphenol(DMP) in the aqueous medium,and potassium ferricyanide was only an oxidant during the oxidative polymerization of DMP.Sodium n-dodecyl sulfate could stabilize polymer particles an...
基金Supported by the Natural Science Foundation of Shanxi Province,China(No.20001057)
文摘Electroanalytical techniques could be a reliable and promising alternative to classical and sophisticated methods because of their simplicity（small and portable）,easy use,the ability to deliver fast response with high sensitivity and selectivity.A square wave voltammetric method was developed for the assessment of organophosphorus（OPs） compound impact on acetylcholinesterase（AChE） of Pheretima with 2,6-dimethyl-p-benzoquinone（2,6DMBQ） as a redox indicator.The substrate of acetylthiocholine is hydrolyzed by AChE and the produced thiocholine reacts with 2,6-DMBQ to give an obvious shift of electrochemical signal.The reduction peak of 2,6-DMBQ is located at around 0.18 V which is far away from the oxidation potential of possible interference components often present in biosample.The decreased rate of reduction current was related with the activity of AChE.The inhibition of parathion-methyl on AChE was assessed.The inhibiton rate of OPs on AChE activity increased quickly during the first 10 min inhibition,and after that the value of inhibition rate approached to be constant.AChE lost almost 29.3% of activity after 10 min incubation with 1 μg/mL parathion-methyl and 67.5% of activity with 10 μg/mL parathion-methyl,while the activity that corresponds to 40 μg/mL parathion-methyl was nearly completely inhibited（94.9%）.Compared to cyclic voltammetry and amperometry,Square wave voltammetry（SWV） method is a high sensitive electroanalysis with fast scan-rate（only several seconds for one signal value） which is useful to prevent the electrodes from possible fouling or passivation.This method can be employed to assess the inhibition of organophosphate on AChE and investigate OPs impact on environmental animals.
文摘Eight rare earth metal （ Ⅲ ） complexes with 2- （ （（4,6-dimethyl）-2-pyrimidinyl） thio）-acetic acid, LnL3· n H2O [HL = 2-（（（4,6-dimethyl）-2-pyrimidinyl）thio）-acetic acid; Ln = La, Ce, Pr, Nd, Sm Eu, Gd, Tb; n = 4 or 5], were prepared and characterized by elemental analysis, complexometric titration, thermal analysis, conductivity, IR and ^1H- NMR. The results reveal that carboxyl group of the hgand coordinates with rare earth ions in bidentate mode after deprotonated. The water molecules exist as crystal water in the complexes. The anti-tumour activities of HL and some complexes were tested by both the MTT and SRB methods. The results show that the suppression ratios of some complexes against the tested tumour cells （HL-60 human leukemia cell lines, BGC-823 human gastric carcinoma cell lines, hela human cervix adenocarcinoma cell lines and Bel-7402 human hepatic carcinoma cell lines） are superior to HL.
基金the Guangdong Natural Science Foundation(No.8151063201000016)the National Natural Science Foundation of China(No.20672046) for financial support
文摘In the presence of diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate（DHP） and a catalytic amount of potassium iodide,severalα-halo ketones were easily reduced to the corresponding ketones in acetone media.The procedure presented here showed several merits such as short reaction time,practical experimental and isolated procedure,and excellent yields of products.
基金Supported by the Natural Science FoundationofChina(No.2 0 0 6 2 0 0 1) ,and the Natural Science Foundation ofGuangxi Province( No.0 135 0 2 0 and No.0 0 0 70 16 )
文摘The facile and efficient total syntheses of monoterpenoid acid 7a and its ester 7b, isolated from Artemisia siebert and Piper aduncum respectively, can be completed in four steps with an overall yield 41%.
文摘2,6-Dimethylnaphthalene (2,6-DMN) is a key intermediate for polyethylene naphthalate synthesis. The selective synthesis of 2,6-DMN from naphthalene and methanol was carried out over different zeolites (HZSM-5, Hβ, HUSY and SAPO-11) modified by 0.1wt% PdO under atmospheric pressure. Among the adopted zeolites, SAPO-11 exhibits exceptional shape-selectivity and stability to synthesize 2,6-dimethylnaphthalene from methylation of naphthalene, due to the special pore structure of SAPO-11 which inosculated better with 2,6-dimethylnaphthalene than with 2,7-dimethylnaphthalene.
基金Supported by the Science and Technology Projects of Chongqing Municipal Education Commission(KJ120663,KJ100602,KJ120632,KJ130638)Chongqing Normal University Scientific Research Foundation Project(2011XLS30)Program for Innovation Team Building at Institutions of Higher Education in Chongqing(KJTD201309)
文摘A new metal-organic coordination polymer [Zn2（trz）2（mpda）（H2O）]n（1, trz = 1,2,4-triazole, H2 mpda = 2,6-dimethylpyridine-3,5-dicarboxylic acid） was synthesized and characterized by single-crystal X-ray analyses. The crystal is of monoclinic system, space group P21/n, a = 9.619（3）, b = 8.920（3）, c = 22.159（6）, β = 96.897（4）°, V = 1887.3（9）3, Z = 4, Mr = 478.04, D3 c = 1.682 Mg/m, F（000） = 960, the final R = 0.0264 and wR = 0.0870（I 2σ（I））. Compound 1 consists of {[Zn4（trz）4]4＋}n layers, which are further connected by mpda2- to complete a three-dimensional structure. The title compound exhibits luminescence at λmax = 415 nm upon excitation at 364 nm.
基金Supported by the National Natural Science Foundation of China(No.21076065)the Natural Science Foundation of Heilongjiang Province of China(No.ZD200820-02)the Science&Technology Research Foundation of Education Bureau of Heilongjiang Province,China(No.11531266)
文摘A highly selective synthesis of 2,6-dimethylnaphthanlene（2,6-DMN） by transalkylation between 2-methylnaphthanlene（2-MN） and 1,2,4,5-tetramethylbenzene（TeMB） was performed with 1-alkyl-3-methylimidazo- lium aluminum chloride（[Cnmim]Cl-AlCl3） ionic liquids（ILs） as catalysts. The influences of the alkyl group as the organic cation, the acidic strength of [C4mim]Cl-AlCl3 ILs as well as the reaction conditions on the catalytic performance were investigated. [C4mim]Cl-AlCl3 ILs[x（AlCl3）=71%] exhibited high activity and selectivity toward 2,6-DMN. The selectivity to 2,6-DMN and the 2,6-DMN/2,7-DMN ratio reached up to 68.2% and 3.7：1, respectively. The UV-Vis spectrum of TeMB treated by different ILs shows that the protonated degree of TeMB dependeds on the acidity strength of ILs, which has a significant impact on the reaction results. The high protonated degree of TeMB is advantageous to enhancing the conversion of transalkylation and the large stereo-hindrance effect of TeMB is favorable to improving the selecivity to 2,6-DMN.
基金Supported by Jiangsu province of academic scientific research industrialization projects(JHB2011-60)Public Science and Technology Research Funds Projects of Ocean"(201305007)Lianyungang Science and technology project(CG1110)
文摘Two new complexes, [Cu（DMB）2（NAA）2]（1） and [Co（DMB）2（NAA）2]（2）（DMB = 5,6-dimethylbenzimidazole, HNNA = 1-naphthylacetic acid）, were hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy, TGA, PXRD and single-crystal X-ray diffraction analysis. The coordination geometry of the metal centers is a perfect square plane for 1 and a distorted tetrahedron for 2. In compound 1, the mononuclear units are linked by N–H···O hydrogen bonds to form a 1D chain structure, while mononuclear motifs of 2 are extended via N–H···O hydrogen bonding and π-π stacking interactions into a 2D supramolecular layer. The remarkable catalytic properties of the two complexes for the degradation of Congo red dye have been found.
文摘A charge transfer hydrogen bonded complex between the electron donor (proton acceptor) 2-amino-4,6-dimethylpyridine with the electron acceptor (proton donor) chloranilic acid has been synthesized and studied experimentally and theoretically. The stability constant recorded high values indicating the high stability of the formed complex. In chloroform, ethanol, methanol and acetonitrile were found the stoichiometric ratio 1:1. The solid complex was prepared and characterized by different spectroscopy techniques. FTIR, 1H and 13C NMR studies supported the presence of proton and charge transfers in the formed complex. Complemented with experimental results, molecular modelling using the density functional theory (DFT) calculations was carried out in the gas, chloroform and methanol phases where the existence of charge and hydrogen transfers. Finally, a good consistency between experimental and theoretical calculations was found confirming that the applied basis set is the suitable one for the system under investigation.
