电化学合成2-甲硫基苯并噻唑

以2-巯基苯并噻唑（MBT）为底物，四甲基氯化铵（TMAC）为甲基源，常温常压电解一锅合成2-甲硫基苯并噻唑（MTBT）。取100 mL溶液电解时，电流密度为1.00 A/dm3、n(TMAC):n(MBT) = 3:1、c(MBT)= 0.1mol/L、总电量为理论值（964.85 C）的1.5倍，产物MTBT收率达88%以上。密度泛函理论（DFT）研究认为，TMAC电还原产物三甲胺协助了MBT电氧化，而且促进了MTBT的形成，与实验 结果相符。     

2-巯基苯并噻唑氧化合成苯并噻唑

以2-巯基苯并噻唑为原料,用双氧水进行氧化合成苯并噻唑,从反应原料的含量、反应温度、氢氧化钠含量、酸化时间4个方面优化了合成工艺。结果表明,优化反应条件为:50 mmol双氧水滴加到溶解有25 mmol 2-巯基苯并噻唑的100 mL浓度为0.25 mol/L氢氧化钠溶液中进行氧化,双氧水的滴加时间为30～40 min;反应温度为60～65℃;酸化时间为50～60 min,苯并噻唑收率为85%。     

2-苯并噻唑磺酰氯的合成

以2-巯基苯并噻唑和10%次氯酸钠溶液为原料合成2-苯并噻唑磺酰氯。优化反应条件:当n(2-巯基苯并噻唑)∶n(次氯酸钠)=1.00∶6.12,反应温度为-10℃,反应时间6 h,优化条件下产物收率达85.8%,其结构经ESI-MS和1H NMR确证。     

2-乙硫基苯并噻唑的合成研究

提出了以2-巯基苯并噻唑为原料,碱的醇溶液为反应介质,与溴乙烷反应合成2-乙硫基苯并噻唑的新方法。并探讨了反应温度、时间、碱溶液的浓度对反应收率的影响。优化条件为:70℃反应1.5 h,NaOH溶液浓度为30%。优化条件下2-乙硫基苯并噻唑收率为86.73%(以2-巯基苯并噻唑计)。工艺原料廉价易得,操作简单。     

2-氯代苯并噻唑的合成研究

选用新的相转移催化剂,采用2—巯基苯并噻唑和亚硫酰氯为原料合成2—氯代苯并噻唑∶缩短了反应时间,简化了操作,反应的最佳摩尔比为2—氯代苯并噻唑∶亚硫酰氯=1∶1.2,最佳反应温度为115℃,催化剂用量为2—巯基苯并噻唑重量的0.5％,2—氯代苯并噻唑的收率为92.7％。     

2-巯基苯并噻唑衍生物的合成方法

介绍了几种2-巯基苯并噻唑衍生物的合成方法,即2-巯基苯并噻唑(MBT)通过选择性的引入-C2H5、-C4H9、-C7H7、-SC8H17-SC7H7、-SC6H5、-SC3H7官能团来合成一系列的衍生物的方法.产物经IR,HNMR和元素分析表明是预想的官能团和结构.     

2—甲硫基—5—甲氧基—苯并噻唑合成方法的研究

以间氨基苯酚为原料，合成２－甲硫基－５－甲氧基－苯并噻唑，原料易得，合成路线短，该化合物用作感蓝染料的中间体。     

2-巯基苯并噻唑

介绍橡胶硫化促进剂2-巯基苯并噻唑的物理性质和主要的制备方法。简要评述了2-巯基苯并噻唑在我国和日本的生产及需求现状,同时概述了2-巯基苯并噻唑作为促进剂的应用范围及其国内外价格。     

铜-2-巯基苯并噻唑含量测定的高效液相色谱研究

建立了测定铜-2-巯基苯并噻唑含量的高效液相色谱方法。用ODS-C18柱分离,以乙腈和醋酸铵水缓冲溶液为流动相,并对方法的线性,精密度,重复性和回收率进行了考察,结果表明利用高效液相色谱法能够方便准确的测定铜-2-巯基苯并噻唑含量。     

Poly(arylenecarbonate)s oligomers by carbonate interchange reaction of dimethyl carbonate with bisphenol-A

Summary Fast atom bombardment mass spectrometry (FAB-MS) has been used to identify oligomers with different end groups obtained by the carbonate interchange reaction of bisphenol-A with dimethyl carbonate and the partial methanolysis of poly(bisphenol-A carbonate)s. Based on the FAB-MS data, a reaction pathway for the formation of compounds in the synthesized oligomers is proposed.NCL communication No. 5920     

1,1-二甲硫基-2-硝基乙烯的合成

研究了以硝基甲烷和二硫化碳为原料,合成1,1-二甲硫基-2-硝基乙烯。考察了反应温度、反应时间、甲基化试剂、溶剂、投料比等对于反应产物的影响,得到优化工艺条件为:反应温度35℃,反应时间3h。以硫酸二甲酯为甲基化试剂,常温下反应时间3 h,重结晶得1,1-二甲硫基-2-硝基乙烯,收率为84%,产物通过IR、1H-NMR鉴定。     

Synthesis of dimethyl ether (DME) by catalytic distillation

The intrinsic kinetics of liquid phase catalytic dehydration of methanol to dimethyl ether over a macroporous sulphonic acid ion exchange resin was determined in a fixed-bed micro-reactor in the temperature range of 391–423 K and pressures up to 2.0 MPa. The kinetic model based on Eley–Rideal mechanism, as well as the power-rate law model, was adopted for fitting the experimental data. However, the Langmuir–Hinshelwood mechanism is not feasible for describing the dehydration reaction of methanol, as deduced from the macroscopic kinetic data and/or no dependence of methanol conversion on initial methanol concentration in the absence of water at the inlet using acetone as inert solvent. Moreover, an improved process consisting of the combination of a fixed-bed reactor and a catalytic distillation column for the synthesis of DME (Process A) was proposed, and a mathematical model was established, into which the intrinsic kinetics obtained in this work was incorporated. The comparison of operating performance among the improved process, Process B consisting of a fixed-bed reactor and two ordinary distillation columns, and Process C consisting of a catalytic distillation column and an ordinary distillation column was also made. It was found that the improved process is more promising than others in energy consumption, production capacity and column number under the same product purity, and is easy to be implemented based on Process B that is currently used in the actual industrial plants with a long catalyst lifetime.     

苯噻氰

苯噻氰是一种性能优良的杀菌剂,有3种常见合成方法,包括2种2-巯基苯并噻唑法和1种氯甲基化法。一种2-巯基苯并噻唑法是用2-巯基苯并噻唑与溴氯甲烷反应生成2-氯甲基硫代苯并噻唑,2-氯甲基硫代苯并噻唑再与硫氰化钠反应得到苯噻氰;另一种2-巯基苯并噻唑法是先将溴氯甲烷与硫氰化钠反应生成硫氰酸氯甲酯,然后硫氰酸氯甲酯与2-巯基苯并噻唑反应得到苯噻氰。氯甲基化法是先用2-巯基苯并噻唑与多聚甲醛和氯化氢反应生成2-氯甲基硫代苯并噻唑,2-氯甲基硫代苯并噻唑再与硫氰化钠反应得到苯噻氰。     

相转移催化法合成1-(2,3-环氧丙基)-2-甲基-5-硝基咪唑

在相转移催化剂四丁基溴化铵存在下,奥硝唑与碱性溶液反应,脱去HCl,得到1-(2,3-环氧丙基)-2-甲基-5-硝基咪唑。研究了碱性溶液种类、碱性溶液的浓度、催化剂加入量、反应温度对目标产物收率的影响。结果表明,较佳反应条件为:奥硝唑∶四丁基溴化铵(质量比)=0.6,碱性溶液为5%NaOH水溶液,反应温度15℃,反应时间1 h,在此条件下,目标产物收率83.9%,纯度99.4%。对目标产物进行了IR及1H NMR表征,并对催化反应机理进行了分析。     

苄胺与碳酸二甲酯甲基化反应体系热力学分析

采用Benson和Joback基团贡献法对苄胺与碳酸二甲酯反应体系进行了热力学分析,计算了反应体系的焓变、熵变、吉布斯自由能变及反应平衡常数,讨论了反应温度对苄胺与碳酸二甲酯甲基化反应和甲氧羰基化反应的影响.计算结果表明,在373.15-453.15 K之间,甲基化反应为吸热反应,且反应为自发过程,反应平衡常数K(O)...     

2-(2'-(2-甲苯磺酰酯乙氧基)-4'-N-三氟乙酰氨基苯基)苯并噻唑的合成

以邻氨基苯硫酚等为原料,与对氨基水杨酸缩合,再经酰化反应、烷基化反应和酯化反应而制得标题化合物,总收率31.7%.     

Production of biodiesel with glycerol carbonate by non‐catalytic supercritical dimethyl carbonate

New biodiesel production processes comprising one‐step and two‐step supercritical dimethyl carbonate methods have been pioneered. The use of dimethyl carbonate allows the reaction conditions to be mild and thus avoid unwanted deterioration of substrates during reaction. In this process, without any catalyst applied, supercritical dimethyl carbonate converts triglycerides (rapeseed oil) into fatty acid methyl esters (FAME) along with glycerol carbonate as a value‐added by‐product, instead of glycerol. Free fatty acids could be also converted into FAME so that the total yield of biodiesel for both methods resulted in over 96 wt%. In addition, the produced FAME satisfy the fuel requirements for the international standards of biodiesel specification.     

纳米CeO_2催化CO_2与甲醇反应合成碳酸二甲酯的研究

本文介绍了金属催化剂纳米CeO2的制备方法,通过对催化剂结构、性质的表征和催化活性的比较,确定出高效的催化剂,并优化了气固相CO2与甲醇直接合成DMC的反应条件。借此,实验得到以下结果:通过对5种方法制备的纳米CeO2催化剂的比较,发现溶胶凝胶法制备的纳米CeO2催化活性最好,甲醇的转化率可达0.215%,DMC选择性为100%。考察了CO2和甲醇合成DMC的较合适的工艺条件是:反应温度433K,反应压力1.0MPa,催化剂用量0.5g,CO2和甲醇摩尔比2.0,甲醇的转化率可达0.215%,DMC选择性为100%。     

1,3,4-Thiadiazoles and 1,3-thiazoles from one-pot reaction of bisthioureas with 2-(bis(methylthio)methylene)malononitrile and ethyl 2-cyano-3,3-bis(methylthio)acrylate

Bisthioureas reacted with either 2-(bis(methylthio)methylene)malononitrile or ethyl 2-cyano-3,3-bis(methylthio)acrylate to give 1,3,4-thiadiazoles and 1,3-thiazoles. Only, the reactive allyl derivative of bisthioureas reacted with the bis(methylthio)methylene compounds to give 1,3-thiazoles. The mechanism was discussed. The structures of products were proved by MS, IR, NMR and elemental analyses and X-ray structure analysis.