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离子液体的酸性测定及其催化的二苯醚/十二烯烷基化反应 总被引:20,自引:0,他引:20
采用乙腈探针红外光谱法测定了[bmim]Cl/AlCl3类离子液体的酸性.结果表明,乙腈可以区分离子液体的酸类型(Bronsted酸或Lewis酸),同时可以指示离子液体的Lewis酸强度.使用[bmim]Cl/AlCl3类离子液体催化二苯醚与十二烯的烷基化反应,研究了离子液体的酸强度、反应温度和醚烯比对反应的影响,并与AlCl3催化体系进行对比.结果发现,该离子液体对二苯醚与十二烯烷基化反应的催化活性明显高于AlCl3.使用离子液体作催化剂显著提高了烷基化反应的产率,简化了产物的分离与提纯,且对环境友好.当控制反应温度为80℃,原料醚烯摩尔比为7,并采用酸强度适中的离子液体时,目标产物单十二烷基二苯醚的产率接近90%. 相似文献
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氯铝酸室温离子液体介质中Blanc氯甲基化反应的研究 总被引:6,自引:0,他引:6
在卤化1-烷基吡啶,1-甲基-3-烷基咪唑季胺盐和盐酸三甲胺与无水 AlCl3构成的氯铝酸室温离子液体反应介质中,尝试了苯及其衍生物和氯甲醚的 Blanc氯甲基化反应。结果表明底物的不同对反应有较大影响,苯与氯甲醚反应主 要生成氯甲基化产物,而烷基苯与氯甲醚反应则主要生成二苯基甲烷衍生物。反应 具有适中至高的转化率和选择性,依据底物的不同,反应结束后可以和离子液体系 分层,便于产物分离。氯铝酸离子液体具有一定的重复使用性。 相似文献
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氯铝酸室温离子液体中缩醛和缩酮反应 总被引:16,自引:0,他引:16
以取代硫酸等无机酸,实现清洁合成为目的,在1-烷基吡啶和1-甲基-3- 烷基咪唑季胺盐与无水AlCl_3构成的室温离子液体为催化剂和反应介质中,尝试了 醛和酮与甲醇的缩合反应。醛与甲醇反应,产物以缩醛为主,酮与甲醇反应则有相 当量的Aldol缩合产物。依反应底物不同,可获得中至高的转化率和选择性。同时 ,一些产物因不溶于离子液体中而分层,便于产物分离。 相似文献
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氯铝酸室温离子液体介质中正碳十二烯选择环化反应 总被引:3,自引:0,他引:3
在氯化1-丙基-3-甲基咪唑(PMImCl)、氯化1-丁基-3-甲\r\n基咪唑(BMImCl)、氯化1-丁基吡啶(BPCl)和溴化1-乙基吡啶(E\r\nPBr)季铵盐与AlCl3构成的室温离子液体介质中,首次发现正十二碳烯\r\n(简称十二烯)可以高选择性地发生环化反应生成环十二烷.依次在反\r\n应管中加入氯铝酸室温离子液体、乙醇和十二烯,其中AlCl3的量为0.\r\n01mol,AlCl3与季铵盐的摩尔比为2,乙醇为10ml,十二烯为2ml(9.\r\n3mmol).当反应体系中不添加乙醇时,十二烯转化率和环十二烷选择\r\n性仅分别为4.2%和73.1%.这是由于十二烯和氯铝酸离子液体形成\r\n两相体系而不易充分接触,故十二烯转化率和环十二烷选择性较低.当\r\n反应体系中加入乙醇时,十二烯和氯铝酸离子液体体系变为单相,使得\r\n十二烯和氯铝酸离子液体可以充分接触,十二烯转化率和环十二烷选择\r\n性可分别达到12.4%和82.9%.压力对提高十二烯转化率和环十二烷\r\n选择性有很大的影响.p(N2)=3.0~6.0MPa下反应12h,十二烯转\r\n化率和环十二烷选择性可分别达到27.2%和93.8%.反应结束后加热\r\n除去乙醇,产物自动与离子液体分层,便于分离,且离子液体介质可重\r\n复使用. 相似文献
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室温离子液体反应介质中叔丁醇氢酯基化反应的研究 总被引:12,自引:0,他引:12
反应温度为100~140 ℃,CO初始压力为2~6 MPa条件下,研究了室温离子液 体与过渡金属三苯基膦配合物构成的催化反应体系中,叔丁醇与乙醇的氢酯基化反 应。同有机溶剂作为反应介质相比,室温离子液体中具有更好的催化活性,并且叔 丁醇可经羰化反应直接生成特戊酸乙酯,产物与催化体系不溶,可以容易地实现分 离。详细考察了金属配合物、离子液体、温度、压力与时间的不同对反应的影响。 相似文献
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Neithnadka Premsai Rai 《合成通讯》2013,43(17):2891-2896
A simple and efficient synthesis of tert‐butyl ethers from various alcohols and substituted phenols using tert‐butyl bromide in the presence of basic lead carbonate as a catalyst. The catalyst is easily recovered via filtration and can be reused up to three times without appreciable loss of activity. 相似文献
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Simultaneous measurement of methyl tert‐butyl ether and tert‐butyl alcohol in human serum by headspace solid‐phase microextraction gas chromatography–mass spectrometry 下载免费PDF全文
Rui Zhang Yong Mei Yanru Liu Hao Dai Hongfang Xia Xin Zhang Yukang Wu Yingying Gu Xiaowu Peng 《Biomedical chromatography : BMC》2015,29(10):1492-1498
The abundant production of methyl tert‐butyl ether (MTBE) and its widespread use have led to an increase in the potential for human exposure. This work described a simple, fast, sensitive, reliable and low‐cost method for the simultaneous measurement of MTBE and its metabolite, tert‐butyl alcohol (TBA) in human serum by headspace solid‐phase microextraction gas chromatography–mass spectrometry. Extraction conditions were optimized and 40 °C, 10 min, 250 rpm and 0.3 g NaCl for a 1 mL sample were the optimal conditions. This method showed good analytical performance in terms of sensitivity with limits of detection in serum (1 mL) of 0.03 µg/L for MTBE and 0.05 µg/L for TBA, accuracy (mean recovery values) from 75.8% to 85.8%, precision (relative standard deviations) <10% and sample stability (biodegradation) <10% after 28 days. A verification experiment proved the reproducibility and stability of this method as well. Finally the method was used to detect 212 specimens, and the internal dose levels for MTBE in human serum were presented in China. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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IntroductionInthepastfewyears,thecalixareneshaveparticularlyatractedatentionfromresearcherswhohavebeenworkingonhost-guestcomp... 相似文献
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Vikas N. Telvekar 《合成通讯》2013,43(21):2827-2829
tert‐Butyl hypochlorite and tert‐butyl hypobromide react with aldoximes and convert them into hydroximinoyl chloride and bromide, respectively; however, under the same reaction conditions, tert‐butyl hypoiodite deoximates aldoximes and ketoximes to give corresponding aldehydes and ketones in high yield (>94%) in a short reaction time (~20 min). 相似文献
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《Journal of Coordination Chemistry》2012,65(2):141-145
Reaction of tert -butyl isocyanide with [Ir(COD)Cl] 2 and NH 4 PF 6 yields [Ir(CNBu t ) 5 H](PF 6 ) 2 ( 1 ). The hydride ligand is observed by both proton NMR and infrared spectroscopy. Complex 1 is triclinic, P-1, a = 11.307(3), b = 14.619(3), c = 15.486(3) Å, f = 98.204(3), g = 106.851(3), n = 106.953(3)°, Z = 2, 6746 reflections [I S 2 σ (I)], R1 = 0.0397, w R 2 = 0.0984. The closest Ir-Ir interatomic distance within the crystal is 8.6 Å. EPR and cyclic voltammetry studies also support the identity of 1 . 相似文献
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L. Brandsma O. Bj⊘rlo A. C.H.T.M. van der kerk-van Hoof H. W. A. Biessels J. Schuring H. D. Verkruijsse 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):261-264
Abstract Addition of two mol equivalents of t-butyl alcohol to a mixture of powdered arsenic and three mol equivalents of lithium in liquid ammonia gives a suspension of lithium arsenide LiAsH2. Subsequent addition of a large excess of t-butyl alcohol and n-octyl iodide at very low temperatures affords n-octyl arsine in -65% yield. 相似文献
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Contributions to the Chemistry of Phosphorus. 243 On the Oxocyclotetraphosphanes (PBut)4O1–4 Under suitable conditions, the reaction of tetra‐tert‐butylcyclotetraphosphane, (PBut)4, with dry atmospheric oxygen gives rise to the corresponding monoxide (PBut)4O ( 1 ) which has been isolated by column chromatography. The reaction with hydrogen peroxide furnishes a mixture of oxocyclotetraphosphanes (PBut)4O1–4 consisting of two constitutionally isomeric dioxides (PBut)4O2 ( 2 a , 2 b ), the trioxide (PBut)4O3 ( 3 ), and the tetraoxide (PBut)4O4 ( 4 ), in addition to 1 . According to the 31P NMR parameters the oxygen atoms are exclusively exocyclically bonded to the phosphorus four‐membered ring. Which of the P atoms are present as λ5‐phosphorus follows from the different low‐field shifts of the individual P nuclei compared with the starting compound. Accordingly, 1 is 1,2,3,4‐Tetra‐tert‐butyl‐1‐oxocyclotetraphosphane, 2 a and 2 b are 1,2,3,4‐Tetra‐tert‐butyl‐1,2‐dioxo‐ and ‐1,3‐dioxocyclotetraphosphane, respectively, 3 is 1,2,3,4‐Tetra‐tert‐butyl‐1,2,3‐trioxocyclotetraphosphane, and 4 is 1,2,3,4‐Tetra‐tert‐butyl‐1,2,3,4‐tetraoxocyclotetraphosphane. When the oxidation reaction proceeds a fission of the P4 ring takes place. 相似文献
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四叔丁基金属酞菁催化活化CO2与环氧丙烷的环加成反应 总被引:8,自引:0,他引:8
以四叔丁基金属酞菁与三正丁胺等有机碱组成的二元催化体系催化活化CO2与环氧丙烷进行环加成反应制备碳酸丙烯酯.同一种金属酞菁与不同有机碱组成的二元催化体系的催化活性与有机碱的碱性强弱一致.有机碱的用量和反应时间对反应均有一定影响,温度对反应的影响较大.与未取代的金属酞菁相比,四叔丁基金属酞菁表现出更高的催化活性.四叔丁基酞菁镁的催化活性高于四叔丁基酞菁铁,在140℃,以四叔丁基金属酞菁镁/三正丁胺为催化剂,碳酸丙烯酯的产率达90.4%. 相似文献