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1.
制备和表征了三种新型质子酸离子液体: 吗啡啉硫酸氢盐([Hnhm]HSO4)、4-甲基吗啡啉硫酸氢盐 ([Hnmm]HSO4)和SO3H-功能化的4-(3-磺丙基)吗啡啉硫酸氢盐([C3SO3Hnhm]HSO4). 以氯乙酸(CAA)和乙醇合成氯乙酸乙酯的酯化反应考察了它们的酸性和催化活性, 并与1-(3-磺酸基)丙基-3-甲基咪唑硫酸氢盐、1-(3-磺丙基)吡啶硫酸氢盐、1-(3-磺丙基)-2-吡咯烷酮硫酸氢盐等三种具有不同氮杂环的SO3H-功能化酸性离子液体以及浓硫酸相对照. 结果表明, 上述SO3H-功能化离子液体对酯化反应的催化性能比非SO3H-功能化的[Hnhm]HSO4和[Hnmm]HSO4都高, 等同甚至优于浓硫酸. 当反应条件为: n(EtOH)∶n(CAA)∶n([C3SO3Hnhm]HSO4)=1.3∶1∶0.2, 反应温度80 ℃, 反应时间3 h, 酯收率可达93.4%. 而且离子液体经真空干燥重复使用9次, 催化活性仍无明显下降. 以[C3SO3Hnhm]HSO4催化乙酸和不同醇的酯化反应获得较高的酯收率和选择性, 离子液体跟酯产物均能自动分相. 还考察了SO3H-功能化酸性离子液体对奥氏体316不锈钢的腐蚀性. 尽管SO3H-功能化离子液体与硫酸的酸性相近, 但对钢试样的腐蚀率不到硫酸的1/3.  相似文献   
2.
甲烷磺酸盐的合成、表征及其催化酯化反应的性能   总被引:15,自引:0,他引:15  
Methane-sulfonate of copper, cobalt, zinc, lanthanide, praseodymium and neodymium are synthesized and characterized by FTIR and TGA. Methane-sulfonates are used as the catalysts in the esterification of chloroacetic acid with isopropanol. Catalytic activity of methane-sulfonates is studied and compared with other Lewis acids. Under the condition of 1.2/1 molar ratio of isopropanol to chloroacetic acid, 1% catalyst (molar percent of chloroacetic acid), 2.5h reaction time, 80~85℃ temperature and benzene as water-carrying agent. The experi-mental results showed that catalytic activity of Lanthanide methane-sulfonate was the best, the yield of isopropyl chloroacetate reaches 88.7%. Copper methane-sulfonate can be reused for three times without distinct loss of catalytic activity.  相似文献   
3.
The efficient selective oxidation and functionalization of C? H bonds with molecular oxygen and a copper catalyst to prepare the corresponding ketones was achieved with ethyl chloroacetate as a promoter. In this transformation, various substituted N‐heterocyclic compounds were well tolerated. Preliminary mechanistic investigations indicated that organic radical species were involved in the overall process. The N‐heterocyclic compounds and ethyl chloroacetate work synergistically to activate C? H bonds in the methylene group, which results in the easy generation of free radical intermediates, thus leading to the corresponding ketones in good yields.  相似文献   
4.
李永胜  李弘  何炳林 《化学学报》2002,60(8):1485-1489
首次报道以自制氯乙酸降冰片烯甲酯(NMCA)为引发剂的苯乙烯、甲基丙烯酸 甲酯的原子转移自由基(ATRP)本体聚合。详细考察了单体转化与反应时间、产物 分子量及分子量分布间的关系。研究发现,此引发引发甲基丙烯酸甲酯ATRP反应所 得聚合物的分子量分布较宽(PDI = 1.80~2.45),且实测值(GPC)与理论值偏差 较大。而NMCA引发的苯乙烯的ATRP反应可得分子量分布较窄(PDI = 1.54)、实验 值(GPC)与理论值基本吻合的产物。单体转化率随反应时间的变化及产物分子量 随单体转化率变化研究证明这一聚合反应具有活性聚合反应特征。产物的NMR分析 证明所合成产物分子中降冰片烯环上双键未参与聚合反应。  相似文献   
5.
崔玉民 《合成化学》2006,14(6):612-614
以5,10,15,20-四苯基卟啉为原料,经硝化,还原和取代反应合成了新化合物5-(对-β-乙酸乙酯基氨基苯基)-10,15,20-三苯基卟啉,其结构经UV,1H NMR,IR和元素分析表征。  相似文献   
6.
氨基磺酸催化合成氯乙酸正丁酯   总被引:4,自引:0,他引:4  
氨基磺酸能够代替硫酸作为酯化催化剂。研究了以氨基磺酸为催化剂,氯乙酸与正丁醇合成氯乙酸正丁酯。研究了反应的影响因素和催化剂的重复使用性能。当氯乙酸、正丁醇和氨基磺酸的摩尔比为0.05:0.15:0.00773,回流分水90min时,酯收率达82.4%。并以氨基磺酸为催化剂合成了氯乙酸异丁酯、氯乙酸仲丁酯、氯乙酸正戊酯、氯乙酸异戊酯和氯乙酸2-戊酯。  相似文献   
7.
酯化反应广泛应用于有机、生物有机以及相关的精细化学品的合成。在各类催化剂中,Lewis酸兼有均相和多相催化剂的优点。但是部分Lewis酸仍存在一些不足,如铪盐和锆盐虽然具有较高的催化活性,  相似文献   
8.
Thermal decompositions of zinc(II) chloroacetate and its complexes with nicotinamide and caffeine were studied by means of TG/DTG, DTA, IR and mass spectroscopy. Thermal analysis showed that presence of the halogen significantly influenced the thermal decomposition. Decompositions may be characterized as two step reactions (release of nicotinamide or caffeine followed by pyrolysis of the carboxylate anion). Zinc chloride, CO, CO2, CH2O, ClCH2CHO were found in gaseous products of the thermal decomposition.  相似文献   
9.
10.
8‐Hydroxyquinolium chloroacetate ( L1 ) was synthesized and characterized. The results suggest that L1 loses ethyl chloroacetate ion on coordination at low pH (2–5) and consequently it behaves as 8‐hydoxyquinoline ( L2 ). Cu2+, Co2+, Pt4+, Pd2+, Au3+, Ag+ and Nd3+ complexes derived from L2 have been synthesized and characterized using spectral, magnetic and thermal measurements. L2 acts as a neutral bidentate ligand in the case of Cu2+, Co2+, Pt4+, Pd2+ and Nd3+ complexes and as a mononegative bidentate ligand in the case of Au3+ and Ag+ complexes. Octahedral geometry is proposed for Cu2+, Co2+ (grey) and Pt4+ complexes and square‐planar for Co2+ (green), Pd2+ and Au3+ complexes. The bond lengths, bond angles, chemical reactivities, binding energies and dipole moments for all compounds were evaluated using density functional theory and molecular electrostatic potential for L1 . Superoxide dismutase radical scavenger‐like activity and cytotoxic activity of the complexes towards HepG2 liver cancer cells has been screened. Cytotoxicity measurements show that Ag+ and Pd2+ complexes have the highest cytotoxic activity while L1 , Cu2+, Co2+ (grey), Co2+ (green), Pt4+ and Nd3+ complexes have no cytotoxic activity. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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