二氢香芹醇的合成研究

在水和有机溶剂中，在碱性条件下，用相转移催化法，由保险粉一步还原（－）-香芹酮制成了二氢香芹醇。本文就还原剂用量、反应时间、溶剂性质和相转移催化剂的种类对还原反应的影响进行了研究，找出较好的反应条件，使二氢香芹醇的收率达到70％。     

保险粉还原香芹酮制取二氢香芹醇的研究

在水和有机溶济中，在碱性条件下，用相转移催化法，由保险粉一步还原1-香芹酮制成了二氢香芹醇．本文就还原剂用量、反应时间、溶剂性质和相转移催化剂的种类对还原反应的影响进行了研究，找出较好的反应条件，使二氢香芹醇的收率达到70％。     

以咪唑为配体固载金属钯催化剂还原芳香卤化物脱卤研究

合成了咪唑卡宾钯硅胶固载催化剂,通过元素分析对合成的催化剂进行了表征。并在催化剂存在条件下,以水合肼为氢供体,在不同结构芳香有机卤代物水溶液中,对其进行了催化还原脱卤反应。结果表明:催化剂有很好的催化活性。在无氢气条件下,以氢供体水合肼为还原剂,能有效地脱除不同结构芳香有机卤代物中的卤素。研究还表明催化剂容易从反应体系中分离出来,可重复使用。研究为降解水环境中的含卤有机物提供了理论依据及技术方法。     

苯酚催化氢转移制环己酮的新工艺

以3-(三苯基膦)二氯化钌[RuCl2(PPh3)3]作催化剂,甲酸钠为氢供体,研究了氢转移催化苯酚加氢制环己酮的新工艺。确定了氢转移加氢过程的适宜反应条件为：甲酸钠和苯酚用量摩尔比为4∶1,反应温度为70 ℃,反应时间为3.0 h,RuCl2(PPh3)3和苯酚用量质量比为5∶100。苯酚的转化率为100%,环己酮产率为95.1%。探讨了以甲酸钠为氢供体的反应过程,发现RuCl2(PPh3)3对苯酚氢转移加氢制环己酮具有优异的催化活性。     

催化剂硫酸氢钾的合成进展

硫酸氢钾是一种廉价、有效和环境友好的合成反应催化剂,硫酸氢钾催化的化学反应具有条件温和、收率较高、后处理工艺简单和环境友好等特点。综述了硫酸氢钾在催化有机合成反应中研究的新进展。     

次磷酸盐在还原碳碳双键上的应用

次磷酸及其盐类在催化剂的作用下,可以还原碳碳双键,碳碳三键,碳氮双键,碳氮三键和碳氧双键.次磷酸盐为氢源的氢转移反应经济安全无污染,它还原有机化合物的反应及产物结构也独特之处.本文对次磷酸盐作为氢源在碳碳双键还原上的应用做了一些综述.     

电催化氮气还原合成氨反应中抑制水解析氢竞争的研究进展

传统工业合成氨Haber-Bosch工艺条件要求严苛,并且存在高能耗以及高CO₂排放问题。电催化氮气还原（nitrogen reduction reaction, NRR）是一种在常温常压下利用氮气合成氨的新工艺,具有成本低、反应条件温和、环境友好等优势。但该反应所需过电位较高,水解析氢反应（hydrogen evolution reaction, HER）竞争明显,导致电流密度和选择性较低,无法达到工业应用水平。本文在介绍电催化NRR合成氨的反应机理的基础上,主要从氮气分子的吸附活化和电还原阶段反应过程出发,综述了电催化氮气还原合成氨反应中HER与NRR的竞争机制。重点梳理了通过设计催化剂和反应体系抑制HER的国内外最新研究成果,最后对电催化NRR合成氨面临的挑战和机遇进行了展望。     

氧化物催化剂在不饱和醛/酮氢转移反应中的应用

不饱和醇是非常重要的有机合成中间体,可通过相应不饱和醛/酮催化加氢还原,其中氢转移还原反应最为简单高效。因此,制备高效醛/酮氢转移反应催化剂成为国内外研究的热点。氧化物催化剂在氢转移反应中具有良好的催化剂活性及选择性,文章综述了氧化物催化剂的制备方法及其应用情况,并对其发展趋势和应用前景作了展望。     

甲酸铵催化转移氢化法制备龙血素A和龙血素B

利用催化转移氢化将查耳酮还原为二氢查尔酮,在反应中研究了以甲酸铵作为氢给予体,Pd/C为催化剂,不同溶剂,不同温度及催化剂的量对反应的影响,并对反应条件进行优化,产率在60%以上。此法与直接加氢还原法比较具有安全性高、反应温度低、设备要求低和选择性高、后处理简单等优点,该法在二氢查尔酮的制备中得到较好结果,具有较广泛的用途。     

钴基催化剂上氢解反应的研究

制备了一系列不同金属含量的Co/SiO2加氢催化剂,考察了催化剂非原位还原条件、进料空速、氢分压变化对其氢解反应影响。结果发现,钴基催化剂在非原位还原后进行反应时有氢解反应伴随发生。催化剂上金属含量越高、还原温度升高和还原时间延长,氢解反应越明显;较高的进料空速及较高的氢分压有助于抑制氢解反应的发生。     

Relative reactivity of hydrogen donor solvent in coal liquefaction

Hydrogen transfer from donor solvent to coal must involve reactions such as hydrogen donation to free radicals and hydrogenation of aromatic structures. The relative reactivities of five typical hydrogen donor solvents, more reactive than tetralin, were determined using a competing elimination reaction in the liquefaction of a bituminous coal at 400 °C and a brown coal at 350 °C. 9,10-Dihydroanthracene, 9,10-dihydrophenanthrene and 1,2,3,4-tetrahydroquinoline exhibited outstanding hydrogen donating ability. Further, the relative reactivities of five mild hydrogen donor solvents such as acenaphthene and indan were determined by a similar elimination reaction using a bituminous coal at 450 °C.     

电解析氢过程中聚吡咯修饰电极的行为

1 INTRODUCTION Hydrogen evolution reaction is an important reaction to produce high purity hydrogen for use in applications such as fertilizers (synthesis of ammonia),food (hydrogenation of fats and oils),petrochemical industry(hydrocracking of petroleum), metallurgical industry (reducing agent in the metallurgical and semiconductors industries) and alkaline production. The main operating cost of the process is the cost of electricity.     

催化剂和芳烃及硫对1—甲基萘以及二（1—萘）甲烷反应的影响

在温和反应条件下探讨了催化剂,芳烃及硫对金属催化剂催化的１－甲基萘（１－ＭＮ）及二９１－萘）甲烷（ＤＮＭ）加氢反应的添加效应,结果表明：Ｆｅ和Ｎｉ对促进１－ＭＮ和ＤＮＭ的加氢非常有效,而供氧溶剂和多环芳烃却显著降低１－ＭＮ和ＤＮＭ的加氢转化率,加入硫显著障碍了加氢反应,却大大促进芳烃加氢裂解反应,初步探讨了有关的反应机理。     

Ruthenium (II) complexes immobilized on swellable polyacrylate matrices: Synthesis and catalytic applications

RuH₂(PPh₃)₄ has been immobilized on swellable polyacrylate matrices to provide heterogenized carboxylate-derivatives. These swellable polymer supported ruthenium (II) complex catalysts have been used in the transfer hydrogenation of aldehydes. Hydrogen donors are formate salt, cyclohexanol, and benzyl alcohol. The catalysts exhibit good activity for hydrogen transfer reduction of aldehydes. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Water-Induced Degradation of Barium Titanate Ceramics Studied by Electrochemical Hydrogen Charging

Water-induced degradation of barium titanate (BTO) ceramics has been investigated using electrochemical hydrogen charging, in which the silver electrodes of BTO ceramic specimens are made cathodes in a 0.01 M NaOH solution to evolve hydrogen by electrolysis of water. After 80 h of treatment, the resistance of BTO decreases by ∼3 orders of magnitude, and the dielectric loss obviously increases. The degradation can be explained by the reduction reaction of atomic hydrogen with BTO. Hydrogen acts as a donor in BTO, and electrons are formed by the reduction. It is proposed that the reduction reaction of atomic hydrogen at ambient temperature by electrolysis of water is an important origin for degradation of BTO-based ceramic devices.     

Impedance measurements in catalysis: charge transfer in titania supported noble metal catalysts

Hydrogen treatment of Pt/TiO₂ leads to an exceptional increase in electric conductivity even at moderate temperature presumably due to the formation of donor electrons during a superficial reduction process. Interestingly, after cooling to lower temperatures that are typically applied for catalytic reactions the observed high conductivity was largely preserved. The enhanced charge carrier density in titania is assumed to cause a considerable charge transfer between support and metal. In this work we show that this charge transfer is correlated with typical catalytic parameters (e.g. hydrogen adsorption capacity and catalytic activity for a hydrocarbon skeleton reaction). Based on these observations we suggest and discuss a modified charge transfer mechanism in addition to the decoration mechanism as a possible reason for the SMSI effect occurring during hydrogen treatment already at moderate temperatures. Dedicated to Konrad Hayek.     

贮氢合金催化共轭二烯烃类聚合物双键加氢的研究

研究了共轭二烯烃类聚合物在贮氢合金氢化物存在下双键加氢的情况。结果表明AB；型贮氢合金[包括LaNi5和MINi5-x(CoMnAl)8]可催化NBR、NR、BR、SBS等共轭二烯烃聚合物双键加氢，其氢化度分别可达33．5％、31．1％、45．8％、32．3％。采用IR、^1H NMR、碘量分析法等手段对加氢产物进行了分析，表明聚合物中双键加氢的同时，NBR中的-C≡N和SBS中的苯环不受影响。此外。研究结果还表明合金组成、表面处理方式等对贮氢合金催化共轭二烯烃类聚合物双键加氢活性有影响。合金氢化物在共轭二烯烃类聚合物双键加氢过程中具有提供氢源与催化双重功能。     

Promotion of the electrochemical hydrogenation of nitrobenzene at hydrogen storage alloys studied using a solid electrolyte method

The electrocatalytic properties of an AB₅-type hydrogen storage alloy towards the electrochemical hydrogenation of unsaturated organic compounds have been studied by a solid electrolyte method using electrochemical hydrogenation of nitrobenzene as a model reaction. Voltammetric studies reveal that the kinetics of the nitrobenzene electro-reduction on the hydrogen storage alloy electrode is similar to that on a Ni electrode. Aniline and p-aminophenol are produced as the reaction products. Compared to the Ni electrode, the production of aniline is considerably promoted on the hydrogen storage alloy electrode. Modifying the alloy surface with a thin layer of Cu enhances the reaction selectivity and current efficiency for aniline formation. Compared to a Cu electrode, the electrochemical hydrogenation of nitrobenzene to aniline is promoted on the Cu-modified alloy electrode. The hydrogenation promotion effect is attributed to the chemical reaction between nitrobenzene and metal hydrides that are electrochemically generated in situ. Hydrogen storage alloys therefore make it possible to intensify the electrochemical hydrogenation process of unsaturated organic compounds.