新型离子液体介质中长链烯烃氢甲酰化反应

合成和表征了离子液体[Rmim][p-CH3C6H4SO3](R=CH3(CH2)n—, n=3, 7, 11, 15), 并以所合成的离子液体为反应介质, 考察了水溶性铑膦络合物HRh(CO)(TPPTS)3[TPPTS: P(m-C6H4SO3Na)3]对长链烯烃氢甲酰化反应的催化性能. 结果表明, 离子液体[Rmim][p-CH3C6H4SO3]中R基团链长的变化对催化活性具有重要的影响；而在相同离子液体中, 氢甲酰化反应活性随着烯烃链长的增加明显下降. 与文献报道中广泛使用的离子液体[Bmim]BF4、[Bmim]PF6相比, 该催化体系对长链烯烃氢甲酰化反应具有更好的活性和化学选择性, 在3.0 MPa, 100 ℃的条件下, 1-己烯氢甲酰化反应转化频率(TOF)高达2736 h-1. 反应完成后, 水溶性铑膦络合物能很好地溶解在离子液体中, 与有机物自动分层, 催化剂的循环使用易于实现.     

SiO_2负载的磺化三苯膦铑配合物催化高碳烯氢甲酰化及反应中的氘逆同位素效应

水溶性磺化三苯膦铑配合物担载在SiO_2表面制得的负载化水溶性Wilkinson催化剂具较大的比表面积,当1-己烯、1-辛烯、1-庚烯和十一烯酸甲酯等液态高碳烯烃在这种催化剂上于固定床加压流动态反应器中连续进行氢甲酰化催化反应时,产物醛的选择性98～100%,并可在适当过量配体存在下保持较高的催化活性.在这种催化剂上分别于CO用/H_2和CO/D_2气氛下进行烯烃氢甲酰化反应,可观察到显著的氘逆同位素效应.根据分析,初步认为酰基物中间体氢解反应可能是SiO_2负载的磺化三苯膦铑配合物催化剂上高碳烯氢甲酰化的速控步骤.     

铑/双膦配体催化均相内烯烃氢甲酰化反应的研究进展

烯烃氢甲酰化反应是工业上合成醛的重要方法.由于双膦配体良好的配位能力,形成的铑配合物有很好的催化活性,在内烯烃氢甲酰化反应中,可以有效地提高直链醛选择性.本文系统地综述了近年来双膦配体铑配合物催化均相内烯烃氢甲酰化反应的研究进展,讨论了双膦配体结构对催化剂活性和生成直链醛选择性的影响.     

离子液体两相不对称氢甲酰化催化反应的研究

从(R)-BINAP出发制备水溶性磺酸钠盐配体(R)-BINAPS,采用离子液体BF4和PF6为介质,实现其Rh配合物对乙酸乙烯酯的两相不对称氢甲酰化反应.实验结果表明,在以BF4为介质的乙酸乙烯酯不对称氢甲酰化反应中,该催化剂在温和条件下显示出高于相应均相体系的产物ee值和异构醛选择性,并在6次循环使用中,反应产物的ee值、选择性和转化率均无明显改变;在离子液体体系中添加适当的甲苯时,油溶性配体(R)-BINAP与Rh组成的配合物催化剂亦可形成类似的两相反应体系,但其活性和选择性在重复使用中呈明显下降趋势.本文还考察了溶剂体系、膦铑比、温度、压力、时间等的影响,并尝试苯乙烯的两相不对称氢甲酰化反应.     

新型铱配合物催化水作氢源的氢甲酰化反应（英文）

基于不同电子和空间效应的膦配体L1～L4,合成了一系列新型铱配合物Ir-L1～Ir-L4,考察了配体在铱配合物催化水作氢源的氢甲酰化反应中的影响.研究表明,具有较强π-受电子能力的离子型双齿膦配体L4 (~1_(J31P-77Se)=781 Hz)修饰的铱配合物可以同时促进水煤气变换反应和烯烃氢甲酰化反应:以Ir-L4配合物为催化剂, 1-己烯的转化率高达93%,产物醛(直链醛和支链醛)的收率为93%,1-己烯加氢副产物己烷的收率小于1%,表明水作氢源几乎完全抑制了烯烃加氢副反应.此外, Ir-L4催化体系结合离子液体([Me Ph3P]Br)还可实现催化剂的回收循环5次.     

有机胺功能化离子液体中离子型铑(Ⅲ)配合物催化的1-辛烯两相氢甲酰化反应

考察了离子型+3价铑配合物1a和2a作为催化剂前体在1-辛烯氢甲酰化反应中的催化行为.实验结果表明,在无助剂存在下,配合物1a和2a表现出较差的催化性能,而廉价低毒的有机叔胺助剂如三乙胺或N-甲基哌啶可以显著提升配合物1a和2a的催化性能,可获得800 h-1以上的转化频率(TOF).当以哌啶功能化离子液体[PEmim]BF4兼作助剂和溶剂时,不仅可以促进配合物1a和2a对氢甲酰化反应的活性和选择性,还可实现"离子液体-有机"两相氢甲酰化反应,使得锁定在[PEmim]BF4离子液体相中的配合物1a(或2a)催化剂得以简单两相分离和回收循环使用,但在5次循环使用过程中锁定在[PEmim]BF4中的催化剂存在向有机相流失和失活的问题,导致产物壬醛的收率逐渐下降.     

Ru-[bmim]BF4 的制备及催化苯选择加氢反应性能

以离子液体1-丁基-3-甲基咪唑四氟硼酸盐([bmim]BF4)-水混合溶剂为介质,采用化学还原法制备了Ru-[bmim]BF4催化剂,并利用紫外-可见光谱、红外光谱、透射电镜、X射线衍射和X射线光电子能谱对催化剂进行了表征.结果表明,Ru在[bmim]BF4中分散较好,粒径~2nm,且离子液体中咪唑阳离子与部分Ru形成了金属卡宾配合物.利用苯选择加氢反应对该催化剂性能进行了评价,发现Ru-卡宾配合物存在时,催化剂活性较低,但环己烯选择性较高.在本文反应条件下,苯转化率为12.2%,环己烯选择性为40.5%.重复使用该催化剂时,由于Ru-卡宾配合物在反应中转变为Ru0,其催化活性增加,但环己烯选择性下降.继续多次使用该催化剂,其性能基本保持稳定.     

金属离子对RhCl（CO）（TPPTS）2催化1—己烯氢甲酰化反应的影响

在以水溶性铑－膦配合物为催化剂的烯烃氢甲酰化反应中,铑的存在形态及配位结构对烯烃氢甲酰化反应的转化率及选择性起着决定性的作用．在反应过程中,特别是工业生产过程中,会由于各种原因导致一些杂质进入反应体系,这些杂质可能会影响铑－膦配合物催化剂的性质,改变...     

水溶性铑—膦配合物催化长链烯烃氢甲酰化反应研究—反应条件的影响

本文研究了两相催化体系中，在ＣＴＡＢ（Ｃ１６Ｈ３３ＮＭｅ３Ｂｒ）存在下，水溶性铑－膦配合物ＲｈＣｌ（ＣＯ）（ＴＰＰＴＳ）２对１－己烯氢甲酰化反应的催化性能，详细考察了反应温度、压力、膦／铑比等对催化活性的影响。结果表明，在１．０ＭＰａ恒压下，反应温度１００℃，膦／铑摩尔比为１６，Ｈ２：ＣＯ＝１：１的条件下，１－己烯氢甲酰化的转化频率（ＴＯＦ）可达到３９．８ｍｉｎ＾－１。在此反应条件下，有机相和水相     

水溶性铑－膦配合物催化长链烯烃氢甲酰化反应研究──反应条件的影响

本文研究了两相催化体系中，在ＣＴＡＢ（Ｃ＿（１６）Ｈ＿（３３）ＮＭｅ＿３Ｂｒ）存在下，水溶性铑－膦配合物ＲｈＣｌ（ＣＯ）（ＴＰＰＴＳ）＿２对１－己烯氢甲酰化反应的催化性能，详细考察了反应温度、压力、膦／铑比等对催化活性的影响。结果表明，在１．０ＭＰａ恒压下，反应温度１００℃，膦／铑摩尔比为１６，Ｈ＿２：ＣＯ＝１：１的条件下，１－己烯氢甲酰化的转化频率（ＴＯＦ）可达到３９．８ｍｉｎ￣（－１）。在此反应条件下，有机相和水相容易分离，铑－膦配合物流失到有机相中的量极小。     

离子液体[BMim]BF4对SDS水溶液表面活性和聚集能力的促进

采用表面张力测定法和核磁共振谱等方法研究了阴离子表面活性剂十二烷基硫酸钠(SDS)在水溶性室温离子液体[BMim]BF4/水混合溶剂中的表面性质及聚集行为, 发现极少量[BMim]BF4的介入就可以显著降低SDS的临界胶束浓度, 提高体系的表面活性; 且[BMim]BF4在混合溶剂中所占的摩尔分数(x1)在一定范围内(0相似文献   

高活性离子液体-铑膦络合物体系催化1-己烯氢甲酰化反应

 The hydroformylation of 1-hexene catalyzed by rhodium-TPPTS complexes in the ionic liquid [bmim]BF4 was studied. The activity and selectivity of the rhodium-TPPTS complexes in [bmim]BF4 were much higher than those reported in other ionic liquids. The TOF of 1-hexene and selectivity for aldehyde were 1508 h-1 and 92%, respectively, under the optimum conditions. The high activity of the catalyst is ascribed to the absence of halide ions as well as the much higher solubility of hydrogen and rhodium-TPPTS complexes in [bmim]BF4 than in [bmim]PF6.     

室温离子液体中乙酸钠和氯苄催化合成乙酸苄酯

在多种1，3-二烷基咪唑和烷基吡啶室温离子液体中考察了较温和条件下乙酸 钠和氯化苄作用合成乙酸苄酯反应。在反应温度下（60 ℃），熔融的三水合乙酸 钠与离子液体相混溶，氯苄同乙酸钠作用得到乙苄酯，它与四氟硼酸1-乙基-3-甲 基咪唑离子液体不溶而分层。反应结束后产物乙酸苄酯可直接倾析得到，乙酸苄酯 产率达到90%，纯度超过99%。此离子液体催化体系简化了产物分离，离子液体可以 重复使用。     

Preparation of fructone catalyzed by water-soluble Brφnsted acid ionic liquids

Fructone(2-methyl-2-ethylacetoacetate-1,3-dioxolane),a flavouring material,has been synthesized from ethyl acetoacetate and glycol using five water-soluble Br(?)nsted acid ionic liquids as catalysts for the first time.The used Br(?)nsted acid ionic liquids include [Hmim]Tfa,[Hmim]Tsa,[Hmim]BF_4,[Bmim]HSO4,[Bmim]H_2PO_4,and[Hmim]BF_4 showed the highest catalytic activity for the preparation of fructone.After reaction,the product could be isolated from the reaction system automatically,and the ionic liquid could be directly reused without dehydration.     

Nitrile-functionalized pyridinium ionic liquids: synthesis, characterization, and their application in carbon-carbon coupling reactions

A series of relatively low-cost ionic liquids, based on the N-butyronitrile pyridinium cation [C(3)CNpy](+), designed to improve catalyst retention, have been prepared and evaluated in Suzuki and Stille coupling reactions. Depending on the nature of the anion, these salts react with palladium chloride to form [C(3)CNpy](2)[PdCl(4)] when the anion is Cl(-) and complexes of the formula [PdCl(2)(C(3)CNpy)(2)][anion](2) when the anion is PF(6)(-), BF(4)(-), or N(SO(2)CF(3))(2)(-). The solid-state structures of [C(3)CNpy]Cl and [C(3)CNpy](2)[PdCl(4)] have been established by single-crystal X-ray diffraction. The catalytic activity of these palladium complexes following immobilization in both N-butylpyridinium and nitrile-functionalized ionic liquids has been evaluated in Suzuki and Stille coupling reactions. All of the palladium complexes show good catalytic activity, but recycling and reuse is considerably superior in the nitrile-functionalized ionic liquid. Inductive coupled plasma spectroscopy reveals that the presence of the coordinating nitrile moiety in the ionic liquid leads to a significant decrease in palladium leaching relative to simple N-alkylpyridinium ionic liquids. Palladium nanoparticles have been identified as the active catalyst in the Stille reaction and were characterized using transmission electron microscopy.     

An efficient method to synthesize TNAD by the nitration of 1,4,5,8- tetraazabicyclo-[4,4,0]-decane with N20s and acidic ionic liquids

An experimental study was carried out on the direct nitration of 1,4,5,8-tetraaza-bicyclo-[4,4,0]-decane to synthesize 1,4,5,8-tetranitro-1,4,5,8-tetraazabicyclo-[4,4,0]-decane(TNAD) with N2O5 catalyzed by acidic ionic liquids. Various ionic liquids, such as [HMim]X, [(CH2)4SO3HMim]X and [Capl]X(X = pTSO, NO3, HSO4), and various parameters such as equivalents of ionic liquid, molar ratio of N2O5 to the starting material, reaction time and temperature, and solvent were investigated. Ionic liquid [(CH2)4SO3HMim]HSO4 showed better catalytic activity. In the presence of 3% molar ratio of [(CH2)4SO3HMim]HSO4 ionic liquid to the staring material, the yield of 1,4,5,8-tetranitro-1,4,5,8-tetraazabicyclo-[4,4,0]-decane was improved by 6.2% compared to the system without ionic liquid.     

Efficient Lewis acid ionic liquid-catalyzed synthesis of the key intermediate of coenzyme Q10 under microwave irradiation

An efficient synthesis of a valuable intermediate of coenzyme Q(10) by microwave-assisted Lewis acidic ionic liquid (IL)-catalyzed Friedel-Crafts alkylation is reported. The acidity of six [Etpy]BF(4)-based ionic liquids was characterized by means of the FT-IR technique using acetonitrile as a molecular probe. The catalytic activities of these ionic liquids were correlated with their Lewis acidity. With increasing Lewis acid strength of the ionic liquids, their catalytic activity in the Friedel-Crafts reaction increased, except for [Etpy]BF(4)-AlCl(3). The effects of the reaction system, the molar fraction of Lewis acid in the Lewis acid ILs and heating techniques were also investigated. Among the six Lewis acid ionic liquids tested [Etpy]BF(4)-ZnCl(2) showed the best catalytic activity, with a yield of 89% after a very short reaction time (150 seconds). This procedure has the advantages of higher efficiency, better reusability of ILs, energy conservation and eco-friendliness. The method has practical value for preparation of CoQ(10) on an industrial scale.     

Br(o)nsted酸性离子液体在醛醇缩合反应中的应用

合成了一系列Br(o)nsted酸性离子液体并将其应用在醛醇缩合反应中.醛醇缩合产物由于极好的溶剂性质等被广泛用作溶剂和试剂.离子液体[BSmim][OTf]在甲醛和乙二醇缩合生成1,3-二氧五环的反应中表现出了极好的催化活性,甲醛转化率和主产物1,3-二氧五环选择性分别可以达到96.1％和92.4％.对影响离子液体催化性能的因素进行了探索,并对催化反应中的离子液体的用量、反应温度、反应时间以及反应物料比进行了考察.通过Hammett酸度函数法测定了所用到离子液体的酸性,结果表明离子液体酸性与其在缩合反应中的催化活性顺序完全一致,酸性越强催化性能越好.结合实验给出了离子液体[BSmim][OTf]催化甲醛和乙二醇缩合反应的可能的反应机理.该催化剂体系具有良好的催化性能,反应可以在较温和的条件下进行,实现了高活性和高选择性的目标,产物易分离,催化剂重复使用7次,其催化活性基本不变.并将该Br(o)nsted酸性离子液体进一步应用到其他醛(酮)醇缩合反应中.     

On the involvement of NHC carbenes in catalytic reactions by iridium complexes, nanoparticle and bulk metal dispersed in imidazolium ionic liquids

D/H exchange reactions at C2, C4 and C5 of the imidazolium cation were observed in catalytic hydrogenation reactions promoted by classical Ir(I) colloid precursors and [Ir(0)](n) nanoparticles dispersed in deuterated imidazolium ionic liquids indicating the participation of carbene species in this media. However, no D/H exchange reaction was observed in cyclohexene hydrogenation promoted by iridium bulk metal dispersed in the ionic liquid [BMI]-d(3).NTf(2). The D/H labeling experiments suggest that the ionic liquids interact with the metal centers preferentially as aggregates rather than isolated ions.