Recent Advances in Iron Catalyzed Oxidation Reactions of Organic Compounds

Iron-catalyzed oxidation reactions have been increasingly investigated in the past two decades and have seen a major increase in research activity. This review article demonstrates the vigorous research activities in the field based on examples from the most recent literature. Catalyst systems are discussed that are active in the oxygenation of alkanes and alkenes to obtain alcohols, ketones or epoxides. Iron-catalyzed oxidation of alcohols to the corresponding carbonyl units are also included. Enantioselective and heterogeneous catalyst systems are presented as well, and a brief overview of mechanistic pictures is given.     

壳聚糖钯催化剂在合成有机酮反应中的催化作用研究

以壳聚糖为载体,负载金属Pd作为催化剂,研究了其对酰氯和三丁基锡化合物偶联反应的催化活性,详细考察了影响反应的各种因素,得出反应的最佳条件：有机锡试剂与酰氯的用量都是10mmol,催化剂用量0．2g。溶剂丙酮用量20ml。反应时间20h。催化剂可以重复使用,催化剂循环使用5次,偶联反应的产率仍为50％。     

生物油含氧化合物加氢脱氧反应机理研究进展

分析了不同原料制备的生物油含氧化合物的组成差异,综述了生物油中典型含氧化合物（酚类化合物、呋喃类化合物、醚类化合物、酸类和酯类化合物）的加氢脱氧机理,重点介绍了含氧化合物加氢脱氧动力学数据及反应路径;同时,还对生物油加氢精制过程进行了描述,主要论述了生物油加氢精制过程的机制以及O、S、N等杂原子在不同催化剂下的脱除活性;最后指出生物油加氢精制面临的问题是人们对其反应机理了解不够深入,而模型化合物加氢脱氧无法真实反映生物油的反应过程,今后应重点研究不同类型含氧化合物的相互作用和真实生物油的反应机理。     

下Pd/C催化剂催化 松香加氢反应的研究

在超临界CO₂条件下采用Pd/C催化剂进行催化松香加氢反应的研究。超临界CO₂条件与常规条件下反应产物相比较,产品中枞酸、去氢枞酸含量都较常规条件下的氢化松香产品低。详细考察了反应温度、反应时间、催化剂用量、催化剂重复使用对反应的影响。结果表明Pd/C催化剂中Pd的流失是造成催化剂失活的主要原因。     

非晶态雷尼镍催化剂低温催化生物油模型化合物加氢的研究

采用非晶态雷尼镍催化剂,在高压反应釜内对二丙酮醇、糠醛、苯酚和愈创木酚等生物油模型化合物进行低温催化加氢实验,研究了模型化合物催化加氢特性、反应机理以及催化剂性质。实验结果表明:温度是影响此类催化剂活性的最主要因素,温度过高容易导致催化剂晶化而降低催化活性;在反应温度180℃、压力3MPa、反应时间4 h以及催化剂量8%(wt)时,模型化合物的转化率和饱和醇的选择性分别达到100.00%和97.74%以上;在此反应条件催化真实生物油的体系中,饱和醇的收率达到44.00%,p H从4.08升至5.13;通过对模型反应机理的探讨,得出模型主要通过两种加氢方式进行:即不同化合物分别以其O上的孤对电子选择性地与催化剂上的两种活泼态H(弱吸附的Ni-H、游离的原子态氢)进行加氢反应,完成催化加氢过程。     

Ionic Liquids as Solvents for Catalyzed Oxidations of Organic Compounds

This review summarizes the oxidation methods of organic compounds carried out in the presence of a catalyst using ionic liquids or molten ammonium salts as solvents. From an ecological point of view, these procedures are particularly interesting when the catalyst is efficiently immobilized in the solvent, thus leading to a reusable system.     

轻烃中含氧化合物的色谱分析

将2mm的填充柱与0.25mm的毛细管柱串联,就可以将含氧化合物有效分离、准确定量。用于分析乙烯、丙烯、碳四及液化石油气中的甲醇、叔丁醇、二甲醚、甲基叔丁基醚等含氧化合物,效果较好。     

Aerobic Oxidative Iodination of Organic Compounds with Iodide Catalyzed by Sodium Nitrite

Selective and efficient iodinations of organic compounds were achieved by an aerobic oxidative process catalyzed by sodium nitrite using potassium iodide in acidic media. Using the potasasium iodide (KI)/air/sodium nitrite (NaNO₂; cat.)/sulfuric acid (H₂SO₄) iodinating system, activated and moderately deactivated aromatic compounds were exclusively or preferentially iodinated at the para position. In protic solvents ketones and 1,3‐dicarbonyl compounds were iodofunctionalized at the α carbonyl position, while in the case of aryl methyl ketones bearing an activated aromatic ring, the regioselectivity of iodination could be directed by the solvent used. In acetonitrile (MeCN) the aromatic ring was selectively iodinated, while in aqueous rethanol (EtOH) functionalization of the methyl carbon atom took place. Alkenes were transformed to vicinal iodohydrins or vicinal iodoalkoxy derivatives following Markovnikov‐type regioselectivity and anti stereoselectivity, while 1,2‐diiodoalkenes with preferentially E orientation were formed from alkynes.     

有机锡烷在Pd/C催化下与有机卤化物的偶联反应

考察了活性炭负载钯催化剂对有机锡烷和有机卤化物如卤代烷、α－卤代酸酯、α－卤代酮等偶联反应的催化作用,发现该负载钯催化剂对偶联反应具有很高的催化活性,且制备容易,可循环使用。对反应机理进行了研究和探讨,XPS实验表明,催化剂中的钯可以看成是两配位不饱和的,经过氧化加成、金属转换、还原消除过程完成催化反应。     

浅析气相色谱法测定乙烯中含氧化合物

文章主要针对气相色谱法测定乙烯中氧化物的实验展开了探讨,通过结合一系列具体的实验实例,对实验所用仪器及试剂和实验方法作了简要的概述,并系统分析讨论了实验的所得结果,以期能为乙烯工业生产上的分析需要提供有益的参考借鉴。     

球形Pd催化剂应用于对氯硝基苯催化加氢

在聚乙二醇、环己胺和水组成的W/O乳状液体系中,用BH4-还原Pd2+制得了球形纳米Pd催化剂,并用XRD、XPS、TEM等方法表征了催化剂的结构、表面电子态和形貌等。通过催化对氯硝基苯加氢制备对氯苯胺来评价其催化性能。结果表明,该催化剂具备较高的催化活性和选择性,对氯硝基苯转化率达到100%,对氯苯胺的选择性达到99%以上,催化剂稳定性较好可以套用6次以上。     

Partial Oxidation of Hydrocarbons and Oxygenated Compounds on Perovskite Oxides

Research of perovskite oxide catalysts (AB03) with a rare-earth ion as an A-site and a transition metal ion as a B-site has been concentrated on the complete oxidation of hydrocarbons, particularly related to exhaust control, and revealed that they are potential catalysts for deep combustion of hydrocarbons (1). The complete oxidation activities have been reported to be mainly controlled by the physicochemical property of the B-site metal cations such as the electronic configuration of d-electron (2), the binding energy of B-0 bond (3) and the stabilization energy of the crystal field (4), rather than the relatively small and less important effect of the rare-earth ion of the A-site (5) and also improved by the substitution of other metal cations for A- or B-site (6,7). Although it is difficult to find many investigations on the application of perovskite-type oxides to partial oxidation, in this chapter, the movement to the partial oxidation of hydrocarbons and oxygenated compounds using various perovskite oxides as catalysts is summarized.     

Recent Developments in Organic Pigments

Azo, vat and phthalocyanine pigments are discussed briefly. The demand for high-grade pigments has led to the development of new classes of organic pigments, viz. quinacridone, dioxazine, perylene—perinone, fluorubine, pyrrocoline, and isoindolinone pigments. The preparation and properties of these pigments are discussed, particular attention being paid to the range of colours and the fastness properties obtained and to the prospects of commercial development.     

Heterogeneous Asymmetric Hydrogenation of N-Heterocyclic Compounds: Hydrogenation of Tetrahydroisoquinoline Derivatives

The preparation and application of heterogeneous chiral catalysts are described. Heterogeneous Pd, Ir and Ru catalysts were tested in the enantioselective hydrogenations of N-heterocyclic compounds, namely 6,7-dimethoxy-3,4-dihydroisoquinoline and 1-methylene-2-ethoxycarbonyl-6,7-dimetoxy-3,4-dihydroisoquinoline in the presence of optically pure cinchonidine, (S,S)- and (R,R)-Ts-DPEN ligands. Cinchonidine-modified metal catalysts exhibited low ee, whereas catalysts stabilized by triphenylphosphane and modified by (S,S)-Ts-DPEN afforded promising ee values (70–80 %). Immobilized Ru(II)-aminophosphane complexes were found to be active in these hydrogenations producing the corresponding tetrahydroisoquinoline derivatives in high optical purities (up to 97 %). The latter catalysts were characterized by infrared spectroscopy, solid-state MAS NMR spectroscopy and elemental analysis. Recycling of these catalysts showed constant or increasing activities in racemic hydrogenation, whereas the presence of the chiral ligands led to leaching of the active species in the liquid phase.     

杂多化合物应用研究新进展

简要介绍了杂多化合物的基本特性 ,重点对近几年杂多化合物在催化、功能材料(导电材料、磁性材料、分子基材料等 )、药物化学、分析化学等方面的应用作了详细地介绍。     

Selective Hydrogenation of Acetylene on Pd Fiberglass Catalysts

Catalysis in Industry - Key properties of silicate glasses are determined. These include the ability to stabilize the highly dispersed Pd nanoparticles in a bulk of fiberglass (FG), the high...     

有机中间体催化加氢技术进展

介绍了近年来有机中间体催经加氢技术进展,并提出了催化加氢技术的主要影响因素,存在问题及今后发展方向。     

有机铝化合物在有机合成中的应用

有机铝化合物因其产量大、价廉，作为有机金属化合物反应性高，因此在有机合成中应用广泛。本文对有机铝化合物的应用及发展作一简略概述。