共查询到20条相似文献,搜索用时 250 毫秒
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高效液相色谱法同时测定间二甲胺基苯甲酸、间氨基苯甲酸和间硝基苯甲酸 总被引:2,自引:0,他引:2
1 引 言间二甲胺基苯甲酸是重要的染料、医药、农药和有机试剂的中间体 ,尤其是压敏和热敏染料结晶紫内酯的重要中间体之一。随着对结晶紫内酯的需求不断增长 ,国内近几年正在研究开发该产品。本文是伴随以间硝基苯甲酸为原料 ,加氢还原为间氨基苯甲酸 ,再以甲醛甲基化合成间二甲胺基苯甲酸的研究过程的分析测试研究。本方法适用于间二甲胺基苯甲酸产品检测及含有各种中间产物的过程检测。2 实验部分2 .1 仪器和试剂 Waters高效液相色谱仪 (包括 5 15泵 ;772 5I手动进样器 ,2 0 μL定量管 ;4 86紫外检测器 ) ,Anastar… 相似文献
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间羟基苯甲醛制备新方法研究 总被引:1,自引:0,他引:1
间羟基苯甲醛是一种重要的精细化工原料,主要用于药物合成,香料生产及电镀工业等领域。目前工业生产间羟基苯甲醛大都采用苯甲醛的硝化反应、还原反应、重氮化水解和间甲酚的乙酰化反应、氯化反应及水解反应两种方法。由于这两种化学方法反应步骤多,伴生的付产物量多,... 相似文献
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间磺酸基偶氮氯膦(CPAmS)是测定钍优良试剂,本文研究了在β-环糊精及溴化十六烷基三甲基铵存在下,该试剂与La(Ⅲ)的显色反应,并用于钛酸镧烧结物中游离氧化镧的测定,结果满意.1试验部分1.1试剂与仪器La(Ⅲ)标准溶液:按常法配成1.omg·ml~(-1)贮备液,用时稀释为10μg·ml~(-1)工作溶液 相似文献
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用KOH/Al2O3合成N—烷基咪唑 总被引:11,自引:0,他引:11
N-烷基化咪唑类化合物的合成常以咪唑为原料,在强碱的作用下,经烷基化反应而获得。方法有醇钠或氨基钠与咪唑反应,生成咪唑负氮离子,然后再与烷基化试剂反应以及在相转移催化下咪唑与烷基化试剂的反应。近年来,应用无机载体试剂进行各种有机合成反应已引起人们的广泛兴趣。我们以KOH/Al_2O_3为载体试剂合成了10种N-烷基咪唑衍生物,收率一般在80%以上。其中某些反应室温下即可完成,操作十分简便。且载体经再生后使用活性不变。 相似文献
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D. A. Predvoditelev M. A. Malenkovskaya E. E. Nifant’ev 《Russian Journal of General Chemistry》2007,77(10):1715-1717
Synthesis of 10-membered phosphorus-containing macroheterocycles derived from 1,3;1′,3′-dibenzylidene derivatives of dipentaerythritol and trivalent phosphorus compounds, ethyl phosphorodichloridite and ethyl tetraethylphosphorodiamidite, was studied. It was established that the synthesis is controlled by reaction temperature, along with reactant molar ratio. 相似文献
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在强碱性水溶液体系中,以水玻璃为硅源,以铝酸钠为铝源,在类质同晶高硅P沸石晶种导向作用下,反应物中自发生成的A型沸石可转晶为纯相高铝MAP沸石。升高反应温度有利于提高产物的结晶度。由不同温度下的晶化曲线计算出MAP沸石表观生长活化能为59.6kJ.mol^-^1。不用晶种时,同一反应物体系结晶产物为单一的A型沸石。在该反应物体系中,A型沸石的成核活化能与生长活化能分别为40.3和50.7kJ.mol^-^1。MAP高的生长活化能以及A型沸石相对低的成核与生长活化能揭示合成MAP沸石时使用晶种的原因。 相似文献
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Concise Synthesis of 2‐Arylpropanoic Acids and Study of Unprecedented Reduction of 3‐Hydroxy‐2‐arylpropenoic Acid Ethyl Ester to 2‐Arylpropenoic Acid Ethyl Ester by BH3⋅THF
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M. Shahid Islam Syarhabil Ahmad Mary Rose Attu F. Holger Foerstering M. Mahmun Hossain 《Helvetica chimica acta》2015,98(9):1273-1286
We have developed a concise method of synthesizing racemic arylpropanoic acids, which have been widely used as nonsteroidal anti‐inflammatory drugs (NSAIDs). The synthesis involves only four steps from commercially available benzaldehyde. The synthesis incorporates an unprecedented reduction reaction, conversion of 3‐hydroxy‐2‐arylpropenoic acid ethyl ester to 2‐arylpropenoic acid ethyl ester by BH3?THF. The reduction reaction has been investigated and optimized. 相似文献
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An inverted Raman microscope spectrometer has been used to profile the spatial evolution of reactant and product concentrations for a chemical reaction within a microreactor operating under hydrodynamic flow control. The Raman spectrometer was equipped with a laser source at wavelength of 780 nm, confocal optics, a holographic transmission grating, and a charge-coupled device (CCD) detector. The microreactor consisted of a T-shaped channel network etched within a 0.5 mm thick glass bottom plate that was thermally bonded to a 0.5 mm thick glass top plate. The ends of the channel network were connected to reagent reservoirs that were linked to a syringe pump for driving the solutions by hydrodynamic pumping within the channels. The microchannels were 221 micro m wide and 73 micro m deep. The synthesis of ethyl acetate from ethanol and acetic acid was investigated as a model system within the microreactor as Raman scattering bands for each reactant and product species were clearly resolved. Raman spectral intensities of each band were proportional to concentration for each species and hence all concentrations could be quantitatively measured after calibration. By scanning specific Raman bands within a selected area in the microchannel network at given steps in the X-Y plane, spatially resolved concentration profiles were obtained under steady-state flow conditions. Under the flow conditions used, different positions within the concentration profile correspond to different times after contact and mixing of the reagents, thereby enabling one to observe the time dependence of the product formation. Raman microscopy provides a useful complementary technique to UV/VIS absorbance and fluorescence methods for the in situ monitoring and analysis of chemical reaction species having their lowest S(0)-S(1) absorption bands too far in the UV to be of use, due to their probable overlap with the bands from other reactant, product and solvent molecules. 相似文献
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本文报道了由香叶醇为起始原料合成Sarcophytol-B(1)关键中间体--(Z,E,E)-2-异丙基-5,9,13-三甲基十四碳-2,4,8,12-四烯酸乙酯(2)的新途径。其中关键步骤是溴化法呢基三苯基鏻(8)和2-氧代-3-甲基丁酸乙酯(3)的Wittig反应。 相似文献
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The synthesis of the potent antitumor agent (±)-streptonigrin has been achieved in 14 linear steps and 11% overall yield from ethyl glyoxalate. The synthesis features a challenging ring-closing metathesis reaction, followed by elimination and aromatization, to furnish a key pentasubstituted pyridine fragment. 相似文献
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This contribution describes a concise synthesis to ethyl trans-[(4S)-methoxy-(2S)-pyrrolidinylmethoxy]cyclohexanecarboxylate (2b) as a key intermediate of very late antigen-4 (VLA-4) antagonist trans-4-[1-[[2,5-dichloro-4-(1-methyl-3-indolylcarboxyamide)phenyl]acetyl]-(4S)-methoxy-(2S)-pyrrolidinylmethoxy]cyclohexanecarboxylic acid (1). The synthesis employs a reductive etherification as a key reaction using (2S,4S)-1-benzyloxycarbonyl-4-methoxypyrrolidine-2-carboxyaldehyde (12) and trans-4-triethylsilyloxycyclohexanecarboxilic acid ethyl ester (13b). This synthesis provides 2b in 6 steps with 38% overall yield from commercially available starting material. 相似文献