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建立了以磷酸氢二钾-磷酸盐缓冲溶液中添加甲醇为流动相,以反相高效液相色谱同时测定吡啶、2-氨基吡啶、2-甲基吡啶和2-吡啶甲酸的新方法。在流动相为甲醇-0.1mol/L磷酸氢二钾和磷酸缓冲溶液、pH为6.0的最佳条件下,吡啶、2-氨基吡啶、2-甲基吡啶和2-吡啶甲酸的加标回收率分别为98.2%~102.1%、99.1%~101.3%、97.8%~100.7%和99.1%~102.4%;线性范围分别为20~980、18~913、19~943和18~902mg/L;检出限分别为2.0、1.8、1.9和1.8mg/L。本法可同时测定电氧化2一甲基吡啶过程中电解液。 相似文献
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蒽酮1和氯甲基吡啶盐酸盐2在甲苯中回流反应生成10,10-二吡啶甲基-9(10H)蒽酮(3),收率63%~68%;3用硼氢化钠还原生成10,10-二吡啶甲基-9,l0-二氢蒽-9-醇(4),收率87%~90%;蒽醇4在酸催化下发生歧化反应,得到还原产物10,10-二吡啶甲基-9,10-二氢蒽(5)和氧化产物蒽酮3.该歧化反应受催化剂、溶剂和反应温度等影响.当蒽醇4用三氟化硼为催化剂、甲苯为溶剂、回流反应,5的收率达到74%.所合成的新化合物都经1H NMR,13C NMR,MS和元素分析表征确认. 相似文献
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Cr(Ⅲ)-取代磷钨杂多配合物对4-甲基吡啶的电催化氧化作用 总被引:2,自引:0,他引:2
利用Cr(Ⅲ)-取代磷钨杂多配合物PW11O39CrⅢ(H2O)4-的内球电子转移特性,通过与反应活性中心CrⅢ(H2O)第六配位水分子的交换反应,将4-甲基吡啶分子络合修饰到该活性中心上进行阳极催化氧化.可见吸收光谱证实4-甲基吡啶和CrⅢ(H2O)中心进行配体交换反应生成PW11O39CrⅢ(NC6H7)4-;而循环伏安和恒电位电解实验结果表明,修饰在Cr(Ⅲ)活性中心上的4-甲基吡啶分子每一步都经历2电子氧化,依次生成吡啶-4-甲醇,吡啶-4-甲醛和吡啶-4-甲酸.由此提出了一个关于这类反应的分子内电催化模板机制,为过渡金属取代杂多配合物作为间接氧化电催化剂的应用开辟了一条新途径. 相似文献
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为了解决部分啶虫脒原药轻微臭味的问题,对样品进行了HPLC分析,发现其中有四个主要的杂质。经过对杂质富集、分离、纯化,得到并合成了这四个杂质,1-(6-氯吡啶-3-基)-N-((6-氯吡啶-3-基)甲基)-N-甲基甲胺、N?-氰基-N-(6-((N?-氰基-N-甲基亚氨代乙酰胺基)甲基)吡啶-3-基)-N-甲基亚氨代乙酰胺、3-氯-1-醛基三环[2,2,1~(2,6)]庚烷、3-氯-1-氰基三环[2,2,1~(2,6)]庚烷,并分析杂质产生的途径和减少其产生的方法,为啶虫脒合成反应的控制和分析提供了支持。 相似文献
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本文以3-甲基-4-硝基氮氧化吡啶为起始原料,经两步反应合成5-氮杂吲哚。通过单因素实验法研究了温度、N,N-二甲基甲酰胺(DMF)、N,N-二甲基甲酰胺二甲缩醛(DMA)、铁粉等因素对反应的影响。较佳工艺条件下,产品按3-甲基-4-硝基吡啶氮氧化物计总收率为88.57%,较文献[1,2]提高了6%。通过熔点测定、1H NMR对最终产物进行了结构表征。此工艺的优点在于操作简单,反应时间短,成本低,收率高,适合于工业化生产。 相似文献
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A. J. Pardey M. Fernández M. Canestrari P. Baricelli E. Lujano C. Longo R. Sartori S. A. Moya 《Reaction Kinetics and Catalysis Letters》1999,67(2):325-331
Catalysts for the water gas shift reaction prepared from Rh(COD)(amine)2 PF6 (COD=1,5-cyclooctadiene, amine=4-picoline, 3-picoline, 2-picoline, pyridine, 3,5-lutidine or 2,6-lutidine) immobilized on
poly(4-vinylpyridine) in contact with 80% aqueoux 2-ethoxyethanol for 1×10−4 mol Rh/0.5 g of polymer, P(CO)=0.9 atm at 100 °C, are described. The role of the coordinated amine effect on the catalytic
activity was investigated. 相似文献
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A. J. Pardey M. Fernández C. Longo E. Lujano P. Baricelli J. Guerrero S. A. Moya 《Reaction Kinetics and Catalysis Letters》1998,65(2):315-320
The activation studies for catalytic reduction of nitrobenzene to aniline by iridium(I) complexes, [Ir(COD)(amine)2]PF6 (COD=1,5-cyclooctadiene, amine =4-picoline, 3-picoline, 2-picoline, or pyridine) heterogenized on poly(4-vinylpyridine) in
aqueous 2-ethoxyethanol are described. The aniline formation (mmol, based on CO2 formed after 9 h) followed the order: 4-picoline (0.068)>2-picoline (0.052)>3-picoline (0.046)≥pyridine (0.042) for 1.0×10−4 mol Ir/0.5 g of polymer, 0.26 mL of nitrobenzene, 10 mL of 2-ethoxyethanol/water, 8/2, v/v, P(CO)=0.9 atm, at 100°C. 相似文献
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Three new Be(II), Mg(II) and Zn(II) phthalocyaninato(2-) complexes with 4-picoline (4-Mepy) in the crystalline form have been obtained by recrystallization of the respective M(II)Pc in 4-picoline under water-free conditions. BePc and ZnPc in 4-picoline solution form 4 + 1 coordinated complexes, while the 4-Mepy molecules biaxially ligate MgPc. The planar phthalocyaninato(2-) macroring of BePc and ZnPc upon mono-axial ligation by the 4-Mepy molecule adopts the saucer-shape form. The interaction of the central M(II) with the ligated 4-Mepy molecule leads to a deviation of the metal from the centre cavity by ∼0.31 Å and ∼0.35 Å in the Be and Zn phthalocyaninato complexes, respectively. In MgPc, the Pc ring upon biaxial ligation retains a planar configuration. The axial M(II)–N(4-Mepy) bond is longer than the four equatorial M(II)–Niso bonds in Mg and Zn phthalocyaninato complexes, while in the Be complex the opposite relation between the axial and equatorial Be–N bonds is observed. Thermogravimetric analysis for all these compounds exhibits only one slope down, due to the loss of 4-Mepy molecules from the complexes, which transform finally into the respective M(II)Pc complexes in the β-form. 相似文献
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Bhattacharya S Banerjee M Mukherjee AK 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2002,58(12):2563-2569
[60]fullerene has been shown to form 1:1 molecular complexes with pyridine and some methylated pyridines such as 2-picoline, 3-picoline, 4-picoline, 2,6-lutidine and 2,4,6-collidine in CCl4 medium by absorption spectrometric method. Well defined charge transfer (CT) bands have been observed for complexes of C60 with all the pyridines studied except 4-picoline. From an analysis of the trends in the CT absorption bands the ionisation potentials of the methylpyridines have been determined. The electron affinity of C60 has also been determined from the spectral data. The formation constants of the complexes exhibit a very good linear free energy relationship from which the Hammett p parameter for the complexation process is found to be -2.96. 相似文献
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Piotr Tomasik Adam Woszczyk Rudolph A. Abramovitch 《Journal of heterocyclic chemistry》1979,16(6):1283-1286
Oxidation of pyridine, 3-picoline, 3,5-lutidine, quinoline, isoquinoline and acridine with hydrated copper sulfate at high temperatures gives the corresponding pyridones, possibly via the intramolecular reaction of a base - Cu(II) complex. Overall conversions are rather poor. 2- And 4-picolines and their methyl homologues undergo some demethylation under these conditions and some picolinic acid is isolated from 2-picoline. 2- And 4-ethylpyridines give both pyridine and 2- and 4-picoline, respectively. 相似文献
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The densities of pyridine, 2-picoline, 3-picoline, and 4-picoline were measured at elevated pressures (0.1 to 40) MPa at four temperatures over the range (298.15 to 328.15) K with a high-pressure apparatus. The high-pressure density data were fitted to the Tait equation and the isothermal compressibility were calculated with a novel computation procedure with the aid of this equation. 相似文献
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《Analytical letters》2012,45(3):139-145
Abstract Cyclic voltammetry and polarography were used to investigate the complexes formed between hemin and 4-picoline in aqueous ethanol solutions. The number of ligands and the effect of pH on the polarographic wave were determined and used to elucidate the mechanism of the electrode reactions. Cyclic voltammetry confirmed the proposed mechanisms. Equilibrium constants were determined where possible. 相似文献
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Fernando Hung-Low Gabriela C. Uzcátegui Juan Alvarez Marisol C. Ortega Alvaro J. Pardey Clementina Longo 《Reaction Kinetics and Catalysis Letters》2005,84(1):87-92
Summary Rhodium(I) complexes, [Rh(COD)(amine)2](PF6) (COD = 1,5-cyclooctadiene, amine = 4-picoline, 3-picoline, 2-picoline, pyridine, 3,5-lutidine or 2,6-lutidine) immobilized on poly(4-vinylpyridine) in contact with water catalyzed both the hydroxycarbonylation of 1-hexene to propionic acid and the water-gas shift reaction (WGSR). The role of the coordinated amine on the catalytic activity was examined. 相似文献
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Alvaro J. Pardey Fernando Hung-Low Gabriela C. Uzcátegui Marisol C. Ortega Clementina Longo 《Reaction Kinetics and Catalysis Letters》2006,88(2):203-208
Summary In this work, a mechanistic study of the hydroxycarbonylation of 1-hexene to heptanoic acid and the water gas shift reaction
(WGSR) catalyzed by the rhodium(I) complexes, [Rh(COD)(amine)2](PF6) (COD = 1,5-cyclooctadiene, amine = 4-picoline, 3-picoline, 2-picoline, pyridine, 3,5-lutidine or 2,6-lutidine) immobilized
on poly(4-vinylpyridine) in contact with water under CO is discussed. Catalytic cycles for these reactions bearing common
Rh-H catalytic species are proposed. 相似文献
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Germán Gascón Marisol C. Ortega José D. Suárez Alvaro J. Pardey Clementina Longo 《Reaction Kinetics and Catalysis Letters》2008,94(1):85-89
Rhodium(I) complexes, cis-[Rh(CO)2(amine)2](PF6) (amine = 4-picoline, 3-picoline, 2-picoline, pyridine, 3,5-lutidine or 2,6-lutidine) dissolved in an aqueous solution of
tetrabutylammonium hydrogensulfate (N(C4H9)4HSO4), catalyze the water-gas shift reaction (WGSR). The role of the coordinated amine on the catalytic activity was examined. 相似文献