负载型钌催化剂在化工中的应用

综合评述了制备负载型钌催化剂的研究现状,着重探讨了其在化学工业中的研究进展.所涉及的反应包括:氨合成、葡萄糖加氢合成山梨醇、苯加氢制环已烯、苯胺加氢制环己胺与二环己胺、二氧化碳甲烷化、催化湿式氧化等,并对它的应用前景进行了展望.     

钌、镍催化剂在加氢实验中的特性对比

用钌、镍催化剂做葡萄糖间歇加氢实验,根据实验现象及山梨醇的质量,针对钌、镍催化剂的一些特性作了分析对比。钌催化剂在葡萄加氢制备山梨醇工艺中,其选择性、活性优于镍催化剂,山梨醇纯度高。     

碳基材料负载钌催化剂的合成及其在催化加氢反应中的应用

本文综述了不同碳材料载体对负载钌催化剂性能的影响,介绍了常见的碳负载钌催化剂的合成方法及其在芳环加氢反应中的应用,并分析了碳负载钌催化剂在未来发展需要解决的问题及研究方向。     

苯部分加氢制环己烯钌基催化剂研究进展

环己烯是重要的化工原料及中间体,广泛应用于合成纤维及其他工业领域。介绍了苯部分加氢制环己烯的技术路线,该技术路线具有安全环保和节能高效的特点,其中,催化反应体系是该技术的关键要素。重点概述了近年来对液相苯部分加氢催化体系中钌基催化剂的研究,包括催化剂前驱体、催化剂制备方法、载体、助催化剂以及添加剂对催化剂性能和产物选择性等的影响。介绍了已工业化的旭化成和神马集团的苯部分加氢工艺。环己烯的市场前景广阔,苯部分加氢工艺是一条经济效益高的工艺路线,实现催化体系的突破对于该工艺至关重要,但存在催化剂成本高、易失活和环己烯收率低的问题。     

钌炭催化剂的制备及其在芳环加氢反应中的应用

芳环加氢反应是最重要的合成反应之一,钌炭催化剂在芳环加氢反应中具有优异的催化性能。综述钌炭催化剂的制备方法和载体性质对钌炭催化剂的影响以及钌炭催化剂在苯、苯甲酸和对苯二甲酸二甲酯等芳环加氢反应中的应用进展。负载型钌炭催化剂的制备方法主要有浸渍法、沉淀法和升华法,超声辅助浸渍法可将大部分钌纳米粒子引入到炭载体的孔道内部,得到限域型负载钌炭催化剂。而镶嵌式钌炭催化剂主要是指通过原位炭化的方法将钌粒子部分镶嵌在炭的孔壁上,一步得到钌炭催化剂,其制备方法主要有软模板剂法和硬模板剂法。除制备方法外,炭的骨架结构、表面性质及氮掺杂对钌炭催化剂的性能影响也较大。镶嵌式钌炭催化剂具有钌纳米粒子和炭载体之间的相互作用强、催化剂抗流失及烧结性能好,在芳环加氢反应中表现出卓越的催化性能和稳定性。随着新制备技术的出现,新型镶嵌式钌炭催化剂将可能实现产业化。     

一种钌催化剂催化醛的转移加氢反应

本文发明了一种在钌催化剂[(p-cymene) Ru Cl2]2和2,2’-二苯并咪唑配体的作用下,使用催化量的Cs2CO3,成功实现了醛在异丙醇中的转移加氢反应,高产率的得到了一系列伯醇产物。该方法不仅选用了低价易得的异丙醇作溶剂和氢源,而且对反应底物有很好的的适用性。     

浅析新型钌基催化剂脱氯还原及加氢反应一体化反应器

近年来,人们对糖醇的需求日益增加,通过玉米等原料生产葡萄糖、麦芽糖等糖类,然后向糖醇类延伸,大大提高了产品的附加值,提高了市场的占有率,因此糖类加氢反应的研究具有很大的工业前景.糖醇中山梨醇应用广泛,主要作为化工和医药原料使用,因此葡萄糖加氢制备山梨醇工艺成为近年来的研究重点,主要针对催化剂进行改进,以提高催化剂的活性...     

钌炭催化剂表面改性及在苯酚加氢反应的应用

通过软模板法成功在镶嵌式钌炭催化剂Ru-OMC表面包覆介孔二氧化硅,研究了催化剂在苯酚加氢反应中的应用,采用N2物理吸附、扫描透射电镜等手段对催化剂进行了系统的表征。结果表明,介孔二氧化硅包覆层改变了催化剂的亲水性质,使得原本疏水性质的Ru-OMC表面变成了亲水性质,提高了环己烷-水2相体系中苯酚加氢反应的转化频率及分离效率。     

苯选择加氢制环己烯在钌基催化体系中的技术进展

环己烯是一种非常重要的有机化工原料,苯选择加氢制环己烯是获取高产量环己烯的最佳途径。长期以来科研工作者们都致力于开发出具有高选择性高收率制环己烯的钌基催化反应体系,然而环境因素使其在工业上大规模应用受到了限制,因此有必要对该领域进一步的深入研究。绿色催化是当下研究的热点之一,开发具有负载少钌且无需反应添加剂的高亲水性催化剂的这一趋势在今后的绿色化学发展中势必加强,因此苯选择加氢制环己烯的技术开发是一项极富有经济意义与科研挑战性的课题。本文从苯选择加氢的反应工艺技术、发展历程、钌基催化剂的反应体系组成以及反应机理等方面,系统介绍了苯选择性加氢制备环己烯的技术进展。     

钌基氨合成催化剂助剂研究进展

钌基氨合成催化剂由于具有低温、低压活性高的优点,而被誉为第二代氨合成催化剂.为了进一步节约能源,降低能耗,达到工业化的要求,国内外许多学者都在对钌基催化剂进行研究.而钌基催化剂中助剂的加入对催化剂活性有着非常大的影响.本文介绍了助剂的研究现状,对助剂的种类及其在催化反应过程所起的作用进行了总结,并介绍了助剂与载体之间的作用以及助剂我持次序的研究现状,旨在为我国进一步开发研制低温低压新一代氨合成催化剂提供参考.     

Ruthenium Phenylindenyl Complex as an Efficient Transfer Hydrogenation Catalyst

An efficient and green protocol for the transfer hydrogenation of carbonyl and imine compounds is presented. The transformations are catalysed by the inexpensive and easily synthesised complex [RuCl(PPh₃)(3‐phenylindenyl)]. Its catalytic activity was compared to that of the most commonly encountered ruthenium complexes in transfer hydrogenation reactions involving several protypical substrates.     

钌-手性膦配体催化剂在不对称催化氢化反应中的应用

较详细的综述了钌-手性膦配体催化剂在不对称催化氢化反应中的最新应用进展，主要从钌-手性膦配体催化剂在芳基丙烯酸(萘普生、布洛芬等)、酰胺类化合物、酮酯等方面的不对称催化反应中的应用进行综述，文章从催化剂活性、立体选择性、转化率和对映选择性等角度讨论了各种合成方法的优点及不足。     

Selective Hydrogenation of Benzene to Cyclohexene Over Colloidal Ruthenium Catalyst Stabilized by Silica

A colloidal ruthenium catalyst stabilized by silica was prepared through microemulsion processing. Ruthenium colloids with particle size about 4 nm are highly dispersed in silica. The selective hydrogenation of benzene to cyclohexene was studied over the catalyst. Much higher activity and selectivity was obtained compared with its supported counterparts.     

钌、镍催化剂在加氢实验中的特性对比

用钌、镍催化剂做葡萄糖间歇加氢实验,根据实验现象及山梨醇的质量,针对钌、镍催化剂的一些特性作了分析对比。钌催化剂在葡萄糖加氢制备山梨醇工艺中,其选择性、活性优于镍催化剂,山梨醇纯度高。     

精细化工中的催化加氢反应

介绍了精细化工中加氢催化剂的类型及其制备方法,以及精细化工中加氢反应的实际应用。     

齐格勒－纳塔型均相加氢催化剂的制备、性能与应用

本文系统阐述了齐格勒－纳塔型均相加氢催化剂的组成及制备方法，对催化剂的性能及应用领域进行了介绍。     

Application of Tethered Ruthenium Catalysts to Asymmetric Hydrogenation of Ketones,and the Selective Hydrogenation of Aldehydes

An improved method for the synthesis of tethered ruthenium(II) complexes of monosulfonylated diamines is described, together with their application to the hydrogenation of ketones and aldehydes. The complexes were applied directly, in their chloride form, to asymmetric ketone hydrogenation, to give products in excess of 99% ee in the best cases, using 30 bar of hydrogen at 60 °C, and to the selective reduction of aldehydes over other functional groups.     

Enantioselective Hydrogenation of the Tetrasubstituted C=C Bond of Enamides Catalyzed by a Ruthenium Catalyst Generated in situ

The enantioselective hydrogenation of enamides bearing an endocyclic tetrasubstituted carbon‐carbon double bond has been performed in the presence of ruthenium catalyst precursors prepared from Ru(cod)(methallyl)₂, Duphos, or BPE as optically active ligand and HBF₄. This promising catalytic system makes possible the selective cis‐hydrogenation with satisfactory enantioselectivities (up to 72% ee) for this type of tetrasubstituted double bonds.     

Advances in Catalyst Systems for the Asymmetric Hydrogenation and Transfer Hydrogenation of Ketones

Hydrogenation of prochiral ketones using chiral transition-metal catalysts represents the cleanest way to access enantiomerically enriched secondary alcohols, which are important building blocks in fine chemicals synthesis. Despite excellent activity, selectivity and compatibility of metal complexes with variety of functional groups, no universal catalysts exist. In this article we summarize the advances in catalyst systems for the asymmetric homogenous and heterogenous hydrogenation of ketones that have been made in past decade. The development of catalysts is oriented in reaching as high as activity with low catalyst loadings, using “greener’’ conditions, and ensuring good recyclability of catalysts. Even though ruthenium complexes represent the largest part of the catalysts, other metals rapidly penetrate this field.     

Selective Hydrogenation of Amides using Ruthenium/ Molybdenum Catalysts

Recyclable, heterogeneous bimetallic ruthenium/molybdenum catalysts, formed in situ from triruthenium dodecacarbonyl [Ru₃(CO)₁₂] and molybdenum hexacarbonyl [Mo(CO)₆], are effective for the selective liquid phase hydrogenation of cyclohexylcarboxamide (CyCONH₂) to cyclohexanemethylamine (CyCH₂NH₂), with no secondary or tertiary amine by‐product formation. Variation of Mo:Ru composition reveals both synergistic and poisoning effects, with the optimum combination of conversion and selectivity at ca. 0.5, and total inhibition of catalysis evident at ≥1. Good amide conversions are noted within the reaction condition regimes 20–100 bar hydrogen and 145–160 °C. The order of reactivity of these catalysts towards reduction of different amide functional groups is primary>tertiary≫secondary. In situ HP‐FT‐IR spectroscopy confirms that catalyst genesis occurs during an induction period associated with decomposition of the organometallic precursors. Ex situ characterisation, using XRD, XPS and EDX‐STEM, for active Mo:Ru compositions, has provided evidence for intimately mixed ca. 2.5–4 nm particles that contain metallic ruthenium, and molybdenum (in several oxidation states, including zero).