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全氟烷基磺酰亚胺盐催化芳香化合物硝化反应的研究 总被引:8,自引:0,他引:8
利用系列全氟烷基磺酰亚胺盐[M(NPf2)n]作为一种新型的Lewis酸催化剂,用于催化芳香化合物与等摩尔65% (m∶m)硝酸的硝化反应. 通过考察不同的催化剂、反应时间、反应温度和反应介质效应等因素对甲苯硝化的影响,以及比较1 mol% Yb[N(C4F9SO2)2]3催化不同结构的取代芳烃硝化反应的效果,表明全氟烷基磺酰亚胺盐不仅具有环境友好和原子经济的特点,而且是一类比常规Lewis酸更有效的、芳香化合物硝化反应的催化剂. 相似文献
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全氟烷基磺酰亚胺配合物及其催化应用 总被引:4,自引:2,他引:2
介绍了全氟烷基磺酰亚胺(PFSI)配合物的结构、性质及制备,综述了一些全氟烷基磺酰亚胺配合物作为Lewis酸催化剂的最新应用进展,并对其催化应用前景进行了展望. 相似文献
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季铵盐型离子液体中全氟烷基磺酰亚胺盐催化的芳烃硝化反应 总被引:1,自引:0,他引:1
全氟烷基磺酰亚胺盐与季铵型离子液体(Cu(N(C4F9SO2)2)2/[N4446][NTf2] 或 In(NTf2)3/[N4446][NTf2])组成的新催化体系,可以很好的催化芳香族化合物的硝化反应。以氯苯的硝化为例,用硝酸和醋酸酐混合物为硝化试剂,在2mol%的Cu(N(C4F9SO2)2)2或In(NTf2)3催化剂催化下,室温下反应10分钟,氯苯的转化率就可分别达到87.6% 和 90.6%,反应产物的邻/对位比为4.3和4.8。并且这种催化剂与离子液体组成的催化体系很容易被回收,并可以连续使用5次以上。 相似文献
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合成了MCM-41负载的双(全氟烷基磺酰亚胺)催化剂 (HN(SO2Rf)2,Rf为全氟烷基),并用XRD, FTIR, SEM, TG-DTA and N2-吸附技术等对它们的结构进行了表征。将这些负载催化剂(HN(SO2Rf)2/MCM–41)用作对苯二酚和叔丁醇的烷基化反应的催化剂,研究了各种反应条件对该反应的影响。在优化反应条件下,仅用5 mol% HN(SO2C4F9)2/MCM-41催化该反应,可以得到高产率(52.0%)的2-叔丁基对苯二酚。研究结果表明,该新型负载催化剂可以至少重复使用6次,而其催化活性基本不变。 相似文献
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通过溶剂热的方法,成功制备一类具有良好疏水性和强酸性的高分子,聚二乙烯苯-对苯乙烯磺酰基全氟丁基磺酰亚胺(记作H-PDVB-0.3-SSFAI).用于催化水相中长链脂肪酸的酯化反应,可获得88%转化率(24 h);在直接酯化反应体系中,转化率最高能达到95%~96%(5~6 h);催化短链的乙酸和己酸的酯化反应,伯醇和环己醇都能顺利进行,其中,环己醇转化率87%~92%(4 h).催化剂能循环使用至少7次.在无溶剂条件下用于催化另一类酯化反应Pechmann缩合,制备7-羟基香豆素,能在140℃高温下循环使用4次,平均产率约90%.H-PDVB-0.3-SSFAI的良好疏水性、强酸性和丰富多孔性,是影响其催化效率的关键. 相似文献
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酸官能团C4F9SO2NHSO2-通过两步溶胶-凝胶法,链接到SiO2载体上,制备得到一种新型的有机-无机杂化固体酸(PSFSI-MSMA15/SiO2).反应以对苯乙烯磺酰基全氟丁基磺酰亚胺钠(1)为原料,与3-甲基丙烯酰氧基丙基三甲氧基硅烷(MSMA)共聚形成预聚体(2),2与原硅酸四乙酯水解缩合,获得PSFSI-MSMA15/SiO2,负载的酸官能团通过FT-IR,TG/DTG及XPS表征,酸负载量约0.62 mmol/g,热稳定性可达到210℃.实验结果表明,酸组分在水体系中稳定,是一种耐水性强酸.催化性能及可循环性在进一步研究中. 相似文献
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Guilong Li 《合成通讯》2013,43(1):34-43
An efficient acetylation of alcohols and phenols catalyzed by lithium bis(perfluoroalkylsulfonyl)-imide was developed. This acetylation features good yields, mild reaction condtions, and simple workup procedures. Furthermore, the catalyst bearing a long perfluoroalkyl chain is recoverable and readily reusable without losing any activity. 相似文献
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Serenella Medici Massimiliano Peana Alessio Pelucelli Maria Antonietta Zoroddu 《Molecules (Basel, Switzerland)》2021,26(9)
Rhodium is one of the most used metals in catalysis both in laboratory reactions and industrial processes. Despite the extensive exploration on “classical” ligands carried out during the past decades in the field of rhodium-catalyzed reactions, such as phosphines, and other common types of ligands including N-heterocyclic carbenes, ferrocenes, cyclopentadienyl anion and pentamethylcyclopentadienyl derivatives, etc., there is still lively research activity on this topic, with considerable efforts being made toward the synthesis of new preformed rhodium catalysts that can be both efficient and selective. Although the “golden age” of homogeneous catalysis might seem over, there is still plenty of room for improvement, especially from the point of view of a more sustainable chemistry. In this review, temporally restricted to the analysis of literature during the past five years (2015–2020), the latest findings and trends in the synthesis and applications of Rh(I) complexes to catalysis will be presented. From the analysis of the most recent literature, it seems clear that rhodium-catalyzed processes still represent a stimulating challenge for the metalloorganic chemist that is far from being over. 相似文献
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Sheng-Huei Hsiao Perng-Chih Huang 《Journal of polymer science. Part A, Polymer chemistry》1998,36(10):1649-1656
Two sulfonyl group-containing bis(ether anhydride)s, 4,4′-[sulfonylbis(1,4-phenylene)dioxy]diphthalic anhydride ( IV ) and 4,4′-[sulfonylbis(2,6-dimethyl-1,4-phenylene)dioxy]diphthalic anhydride (Me- IV ), were prepared in three steps starting from the nucleophilic nitrodisplacement reaction of the bisphenolate ions of 4,4′-sulfonyldiphenol and 4,4′-sulfonylbis(2,6-dimethylphenol) with 4-nitrophthalonitrile in N,N-dimethylformamide (DMF). High-molar-mass aromatic poly(ether sulfone imide)s were synthesized via a conventional two-stage procedure from the bis(ether anhydride)s and various aromatic diamines. The inherent viscosities of the intermediate poly(ether sulfone amic acid)s were in the ranges of 0.30–0.47 dL/g for those from IV and 0.64–1.34 dL/g for those from Me- IV. After thermal imidization, the resulting two series of poly(ether sulfone imide)s had inherent viscosities of 0.25–0.49 and 0.39–1.19 dL/g, respectively. Most of the polyimides showed distinct glass transitions on their differential scanning calorimetry (DSC) curves, and their glass transition temperatures (Tg) were recorded between 223–253 and 252–288°C, respectively. The results of thermogravimetry (TG) revealed that all the poly(ether sulfone imide)s showed no significant weight loss before 400°C. The methyl-substituted polymers showed higher Tg's but lower initial decomposition temperatures and less solubility compared to the corresponding unsubstituted polymers. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1649–1656, 1998 相似文献
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Dr. Weiwei Fang Yang Zhang Jiajie Wu Cong Liu Dr. Haibo Zhu Prof. Dr. Tao Tu 《化学:亚洲杂志》2018,13(7):712-729
Over the past two decades, supramolecular gels have attracted significant attention from scientists in diverse research fields and have been extensively developed. This review mainly focuses on the significant achievements in supramolecular gels and catalysis. First, by incorporating diverse catalytic sites and active organic functional groups into gelator molecules, supramolecular gels have been considered as a novel matrix for catalysis. In addition, these rationally designed supramolecular gels also provide a variety of templates to access metal nanocomposites, which may function as catalysts and exhibit high activity in diverse catalytic transformations. Finally, as a new kind of biomaterial, supramolecular gels formed in situ by self‐assembly triggered by catalytic transformations are also covered herein. 相似文献
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Covalent organic frameworks (COFs) as an emerging type of crystalline porous materials, have obtained considerable attention recently. They have exhibited diverse structure and attractive performance in various catalytic reactions. It is highly expected to have a systematic and comprehensive review summing up COFs‐derived catalysts in homogeneous and heterogeneous catalysis, which is favorable to the judicious design of an efficient catalyst for targeted reaction. Herein, we focus on summarizing recent and significant developments in COFs materials, with an emphasis on both the synthetic strategies and targeted functionalization, and categorize it in accordance with the different types of catalytic reactions. Their potential catalysis applications are reviewed thoroughly. Moreover, a personal view about the future development of COFs catalysts with respect to the large‐scale production is also discussed. 相似文献