共查询到20条相似文献,搜索用时 15 毫秒
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相转移催化在高分子化合物合成中的应用 总被引:7,自引:0,他引:7
综述了相转移催化用于高分子化合物合成的主要研究进展.介绍了季铵盐类及冠醚类相转移催化剂在高聚物的亲核取代反应、阴离子开环聚合反应及自由基聚合反应中的应用.重点总结了亲核取代反应中聚苯乙烯类化合物的功能化及化学修饰,包括合成路线、反应机理、温度以及催化剂和溶剂的种类与用量等因素对反应的影响.冠醚类化合物的催化效果略优于季铵盐类化合物,而后者的成本低、毒性小、应用更广泛,其催化的反应应作为今后研究的重点,以期将相转移催化技术尽早用于工业化生产. 相似文献
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ZHANG Feng LI Ya-zhuo WANG Yun-xin GAO Da-wei SUN Ji-kui ZHANG Yu-min ZHAO Tian-qi CHEN Xiao-dong 《高等学校化学研究》2007,23(4):486-488
Compounds having an active hydroxy group, such as, acyloins can be easily alkylated by alkyl halides in the presence of a phase transfer catalyst (PTC). The reaction is usually carried out in the presence of con-centrated aqueous sodium or potassium hydroxide and a phase transfer catalyst, such as, quaternary ammonium salts^[1-3] species, miscible which facilitate the interphase transfer of making reactions between reagents in two im-phases possible. The reaction involves a series of equilibrium and mass-transfer steps. 相似文献
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ZHANG Feng LI Ya-zhuo WANG Yun-xin GAO Da-wei SUN Ji-kui ZHANG Yu-min ZHAO Tian-qi CHEN Xiao-dong 《高等学校化学研究》2007,23(4)
Introduction Compounds having an active hydroxy group, such as, acyloins can be easily alkylated by alkyl halides in the presence of a phase transfer catalyst (PTC). The reaction is usually carried out in the presence of concentrated aqueous sodium or potassium hydroxide and a phase transfer catalyst, such as, quaternary ammonium salts[1-3], which facilitate the interphase transfer of species, making reactions between reagents in two immiscible phases possible. The reaction involves a series of equilibrium and mass-transfer steps. 相似文献
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S. Madan Kumar 《合成通讯》2013,43(21):2121-2127
A simple and convenient one-pot preparation method for pure diazo carbonyl compounds under tri-phase phasetransfer catalysis conditions is described. 相似文献
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This communication describes a convenient procedure for the preparation of alkylated derivatives of phenobarbital using phase-transfer catalysis without solvent conditions. 相似文献
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以PEG-400为固液相转移催化剂,通过苯甲酰氯与硒氰酸钾反应合成了中间体苯甲酰基异硒氰酸酯,该中间体不需分离,直接与芳胺反应,得到N-苯甲酰基-N'-芳基硒脲(2a~2p),这些化合物用1HNMR,IR及元素分析进行了表征,并用X射线单晶衍射确定了化合物2k的单晶结构.晶体结构表明,该化合物通过分子间氢键组装成了沿a轴无限延伸的一维链状超分子结构.晶体属于单斜晶系,P2(1)/c空间群,晶胞参数:a=1.1073(1)nm,b=0.5745(1)nm,c=2.4356(5)nm,β=92.10(1)°,V=1.5483(4)nm3,Z=4,μ=2.428. 相似文献
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Adam Nelson 《Angewandte Chemie (International ed. in English)》1999,38(11):1583-1585
Both in the laboratory and industrially , phase-transfer catalysis offers the potential to induce asymmetry into reactions with anionic intermediates. Equation (a) provides an example (conditions: a) 10 mol % phase-transfer catalyst, BnBr, CsOH⋅H2O, PhMe, 15–24 h, −78°C). 相似文献
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以氨和二硫化碳为原料的传统合成硫氰酸铵 ( NH4 SCN)工艺分为加压法 [1,2 ]和常压法 [3,4 ] 2种 .常压法设备投资小 ,操作灵活 ,但常压因互不相溶的 CS2 、NH3两相反应体积小 ,速度慢 ,反应时间达 2 5 h以上 ,且 CS2 易挥发 ,使 NH4 SCN产率仅有 60 %左右 .表面活性剂作为相转移催化剂加快反应速度的应用已有报道 [5] .本文采用壬基酚四氧乙烯醚 ( OP- 4)和壬基酚二十一氧乙烯醚 ( OP- 2 1 )混合型催化剂用于 n( CS2 )∶ n( NH3) =1∶ 2 .5反应体系 ,在常温、常压及高速搅拌下 ,第 1步反应缩短为 4h,NH4 SCN产率提高到 70 %以… 相似文献
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Synthesis of 6-benzyloxypurine and its N-alkylation under phase-transfer conditions represents a high-yield and simple procedure for the preparation of 9- and 7-substituted 6-benzyloxypurines and, therefore, related hypoxanthines. 相似文献
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聚苯乙烯三乙醇胺树脂催化合成对硝基苯甲醚 总被引:2,自引:0,他引:2
:讨论了聚苯乙烯三乙醇胺树脂为相转移催化剂催化合成对硝基苯甲醚的方法 ,探讨了最佳反应条件 ,证实了催化剂的重复使用性能 相似文献
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溶剂和杂多酸盐中季铵阳离子对环己烯环氧化反应控制相转移催化的影响 总被引:10,自引:0,他引:10
考察了溶剂和催化剂Q3[PO4(WO3)4]中季铵盐阳离子对环己\r\n烯环氧化反应的影响.在环己烯环氧化反应中,以氯仿和叔丁醇为溶剂\r\n时,环氧化反应的结果最好.当催化剂中季铵盐阳离子的碳数合适时,\r\n才能形成反应控制相转移催化过程.催化剂本身不溶于反应体系,但在\r\n过氧化氢的作用下形成可溶于反应体系的活性物种,均相地催化环氧化\r\n反应.当过氧化氢消耗尽时,催化剂又恢复到起始结构并从反应体系中\r\n析出. 相似文献
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Unsymmetrical ketones were conveniently prepared from the unsymmetrical diorganyl borinates via the insertion of dichlorocarbene into C? B bond under liquid‐liquid phase transfer catalysis conditions and oxidation with alkaline hydrogen peroxide in 35–67% yields. 相似文献