三苯基膦-氯化钌-DPEN催化取代苯乙酮不对称加氢

用三苯基膦-氯化钌-DPEN配合物作催化剂催化了苯乙酮和几种邻位取代苯乙酮的不对称氢化反应。结果表明：此配合物对苯乙酮和几种邻位取代苯乙酮进行不对称氢化反应具有良好的催化性能和较高的对映选择性，在优化的条件下，其不对称氢化反应的转化率可达到100％，其ee值可达到49％～78％。

一羰基二氢三(三苯基膦)合钌的合成及表征

在碱性条件下,由三氯化钌、三苯基膦与甲醛溶液反应制备了一羰基二氢三(三苯基膦)[RuH_2(CO) (Ph_3P)_3]。考察了三苯基膦、甲醛溶液、碱的种类及用量和溶剂种类及用量、反应时间等对反应的影响。结果表明,在氮气保护、反应温度78℃、氢氧化钾存在条件下,n(三氯化钌):n(三苯基膦):n(甲醛溶液)=1:6:160,乙醇为溶剂,反应时间2 h,RuH_2(CO)(Ph_3P)_3收率可以达到84%以上。对所得的目标产物进行了IR,~1H NMR,^(13)CNMR,^(31)P NMR,UV以及熔点测试等表征。

水溶性钌簇合物Ru_3（CO）_9（dpps）_3催化含官能团烯烃的选择氢化和羰化反应

用水溶性钌簇合物Ｒｕ３（ＣＯ）９（ｄＰＰｓ）３（ｄＰＰｓ＝Ｐｈ２Ｐ—ｍ—Ｃ６Ｈ４ＳＯ３Ｎａ，下同）为催化剂，考察了α，β－不饱和酸、苯乙烯、苯乙酮、苯甲醛和环己酮等的加氢反应。发现了题示簇合物［Ｒｕ３（ＣＯ）９（ｄＰｐｓ）３］是催化上述含官能团烯烃的选择氢化的有效催化剂。在甲醇溶液中，该簇合物也有效地催化乙烯羰化生成丙酸甲酯和二乙酮。添加几种卤化物不仅提高了催化活性，而且改变了产物分布。根据催化剂的ＩＲ和ＸＰＳ分析结果，讨论了可能的催化活性物种。

手性钌螯合催化剂的合成及在α⁃羟基酯的动态动力学氢化反应中的应用

设计并合成了一系列基于(R)-2-(二苯基膦基)-1-苯基-N-(2′-吡啶甲基)-1-乙胺及其衍生物的手性钌螯合催化剂.采用核磁共振波谱及高分辨质谱对其进行表征,并给出单晶结构.以α-羟基酯类化合物为研究对象,通过酯的动态动力学氢化还原反应,发展了一种合成手性二醇的方法.研究结果表明,该催化体系能有效实现酯的氢化还原,并获得一定的对映选择性.

丙烯酸-2,4,6-三硝基苯乙酯的合成及热分解

以TNT、甲醛为原料,在弱碱性条件下反应合成得到2,4,6-三硝基苯乙醇(PicCH2CH2OH);PicCH2CH2OH在浓硫酸催化下和丙烯酸在甲苯中回流反应24h,合成得到丙烯酸-2,4,6-三硝基苯乙酯,产率为62%。采用紫外可见光谱(UV-Vis)、核磁共振氢谱(1HNMR)、红外光谱(FTIR)、质谱(MS)以及元素分析等对产物结构进行了表征。利用热重分析(TG)对产物热稳定性进行了研究,采用Kissinger方法和Ozawa方法计算其热分解活化能Ea分别为99.78,102.96kJ·mol-1。

丁腈橡胶催化加氢反应研究

氢化丁腈橡胶具有良好的耐油性和耐氧性,广泛应用于汽车和石油行业,通过丁腈橡胶溶液均相催化加氢制得,采用铑类和钯类均相催化剂。考察不同溶剂、催化剂及m(Ru)∶m(丁腈橡胶)对丁腈橡胶加氢的影响。采用红外光谱法和核磁法对氢化丁腈橡胶的结构进行分析,筛选出价廉、活性高和选择性高的催化剂。结果表明,在丁腈橡胶加氢反应中,丁酮可作为溶剂,Ru(PPh3)3Cl2催化剂具有高活性和高选择性。在丁酮200 m L、丁腈橡胶5 g、Ru(PPh3)3Cl2催化剂、m(Ru)∶m(丁腈橡胶)=0.000 20∶1、反应温度140℃、氢压8.0 MPa和反应时间4 h条件下,加氢度和选择性均达到100%,具有与Rh(PPh3)3Cl相当的催化性能。

Electronic Communication Between Co and Ru Sites Decorated on Nitrogen-Doped Carbon Nanotubes Boosting the Alkaline Hydrogen Evolution Reaction

Designing highly efficient Pt-free electrocatalysts with low overpotential for an alkaline hydrogen evolution reaction(HER)remains a significant challenge.Here,a novel and efficient cobalt(Co),ruthenium(Ru)bimetallic electrocatalyst composed of CoRu nanoalloy decorated on the N-doped carbon nanotubes(CoRu@N-CNTs),was prepared by reacting fullerenol with melamine via hydrothermal treatment and followed by pyrolysis.Benefiting from the electronic communication between Co and Ru sites,the as-obtained CoRu@N-CNTs catalyst exhibited superior electrocatalytic HER activity.To deliver a current density of 10 mA·cm^(-2),it required an overpotential of merely 19 mV along with a Tafel slope of 26.19 mV·dec^(-1)in 1 mol·L^(-1)potassium hydroxide(KOH)solution,outperforming the benchmark Pt/C catalyst.The present work would pave a new way towards the design and construction of an efficient electrocatalyst for energy storage and conversion.

Promoting role of Ru species on Ir-Fe/BN catalyst in 1,2-diols hydrogenolysis to secondary alcohols

Noble metal-based-bimetallic catalysts have been highly investigated and applied in wide applications including biomass transformation via regioselective C−O hydrogenolysis while further modification especially with noble metal is highly promising yet still under investigation.Herein,Ru was found as an effective modifier among the screened noble metals(Ru,Pt,Rh,Pd,Au,and Ag)for Ir-Fe/BN(Ir=5 wt%,Fe/Ir=0.25)catalyst in terminal C−O hydrogenolysis of 1,2-butanediol(1,2-BuD)to 2-butanol(2-BuOH).Only trace amount of Ru(up to 0.5 wt%)was effective in terms of high 2-BuOH selectivity(>60%)and activity(about twice).Larger amount of Ru species(3 wt%)highly enhanced the activity but gave low selectivity to 2-BuOH with by-products of terminal C−C bond scission.Optimized catalyst(Ru(0.5)-Ir-Fe/BN)was reusable at least 4 times and gave moderate 2-BuOH yield(47%)in hydrogenolysis of 1,2-BuD.The promoting effect of Ru addition(0.5 wt%)to Ir-Fe/BN on hydrogenolysis of various alcohols was also confirmed.Combining catalytic tests with various characterizations,the promotion mechanism of Ru species in trimetallic catalysts was clarified.The Ru species in Ru(0.5)-Ir-Fe/BN form alloy with Ir and are enriched at the interface with BN surface,and direct interaction between Ru and Fe was not necessary in Ru-Ir-Fe alloy.The interface of Ir and Fe on the surface of Ir-Fe alloy may work as active sites for 1,2-diols to secondary alcohols via direct C−O hydrogenolysis,in which Ru-modified Ir activates H_(2) to form hydride-like species.The activity of Ru species in C−C bond cleavage was highly suppressed due to the direct interaction with Ir species and less exposed to substrate.Larger loading amount of Ru species(3 wt%)led to the formation Ru-rich trimetallic alloy,which further works as active sites for C−C bond scission.

RuHCl(PPh_3)_3的简便合成及其无溶剂条件下催化1-十八烯双键异构化研究

以RuC l2(PPh3)3为原料,EtOH/KOH组合试剂为氢供体,通过升温方式控制,方便地合成了产率为91.9%的RuHC l(PPh3)3,其结构用NMR、MS、IR、IE和ICP得到了表征;通过IR,NMR分析研究表明,反应经过了[Ru]-OEt中间体过程.用RuHC l(PPh3)3作为催化剂,无溶剂条件下可以有效地催化1-十八烯的双键异构化,在180℃时,催化剂与1-十八烯的摩尔比为1∶200,反应时间为24 h时,1-十八烯的转化率为94.6%.

Efficient and stable Ru(Ⅲ)-choline chloride catalyst system with low Ru content for non-mercury acetylene hydrochlorination

Herein,we report an excellent,supported Ru(III)‐ChCl/AC catalyst with lower Ru content,where the ionic complex ChRuCl4 serves as the active component for acetylene hydrochlorination.The prepared heterogeneous Ru‐10%ChCl/AC catalyst shows excellent activity and long‐term stability.In this system,ChCl provides an environment for the ChRuCl4 to be stabilized as Ru(III),thus suppressing the reduction of the active species and the aggregation of ruthenium species during the reaction.The interaction between reactants and catalyst species was investigated by catalyst characterizations in combination with DFT calculations to disclose the effect of the ChRuCl4 complex and ChCl on the catalytic performance.This inexpensive,efficient,and long‐term catalyst is a competitive candidate for application in the hydrochlorination industry.

Study on Chemisorption and Desorption of Hydrogen and Nitrogen on Ru-based Ammonia Synthesis Catalyst

The effects of promoters K, Ba, Sm on the chemisorption and desorption of hydrogen and nitrogen, dispersion of metallic Ru. and catalytic activity of active carbon (AC) supported ruthenium catalyst for ammonia synthesis have been studied by means of pulse chromatography, temperature-programmed desorption, and activity test. Promoters K, Ba and Sm increased the activity of Ru/AC catalysts for ammonia synthesis significantly, and particularly, potassium exhibited the best promotion on the activity because of the strong electronic donation to metallic Ru. Much higher activity can be obtained for Ru/AC catalyst with binary or triple promoters. The activity of Ru/AC catalyst is dependent on the adsorption of hydrogen and nitrogen. The high activity of catalyst could be ascribed to strong dissociation of nitrogen on the catalyst surface. Strong adsorption of hydrogen would inhibit the adsorption of nitrogen, resulted in decrease of the catalytic activity. Ru/AC catalyst promoted by Sm2O3 shows the best dispersion of metallic Ru, since the partly reduced SmOx on the surface modifies the morphology of active sites and favors the dispersion of metallic Ru. The activity of Ru/AC catalysts is in accordance to the corresponding amount of nitrogen chemisorption and the desorption activation energy of nitrogen. The desorption activation energy for nitrogen decreases in the order of Ru>Ru-Ba>Ru-Sm>Ru-Ba-Sm>Ru-K>Ru-K-Sm>Ru-K-Ba>Ru-K-Ba-Sm, just opposite to the order of catalytic activity, suggesting that the ammonia synthesis over Ru-based catalyst is controlled by the step of dissociation of nitrogen.

Ru surface density effect on ammonia synthesis activity and hydrogen poisoning of ceria-supported Ru catalysts

Evaluating the effect of metal surface density on catalytic performance is critical for designing high-activity metal-based catalysts.In this study,a series of ceria(CeCO_(2))-supported Ru catalysts(Ru/CeCO_(2))were prepared to analyze the effect of Ru surface density on the catalytic performance of Ru/CeCO_(2) for ammonia synthesis.For the Ru/CeCO_(2) catalysts with Ru surface densities lower than 0.68 Ru nm^(-2),the Ru layers were in close contact with CeCO_(2),and electrons were transferred directly from the CeCO_(2) defect sites to the Ru species.In such cases,the adsorption of hydrogen species on the Ru sites in the vicinity of 0 atoms was high,leading to a high ammonia synthesis activity and strong hydrogen poisoning.In contrast,the preferential aggregation of Ru species into large particles on top of the Ru overlayer resulted in the coexistence of Ru clusters and particles,for catalysts with a Ru surface density higher than 1.4 Ru nm^(-2),for which Ru particles were isolated from the direct electronic influence of CeCO_(2).Consequently,the Ru-Ceth interactions were weak,and hydrogen poisoning can be significantly alleviated.Overall,electron transfer and hydrogen adsorption synergistically affected the synthesis of ammonia over Ru/CeCO_(2) catalysts,and catalyst samples with a Ru surface density lower than 0.31 Ru nm^(-2) or exactly 2.1 Ru nm^(-2) exhibited high catalytic activity for ammonia synthesis.

Chiral BINAP-based hierarchical porous polymers as platforms for efficient heterogeneous asymmetric catalysis

Two vinyl‐functionalized chiral2,2'‐bis(diphenylphosphino)‐1,1'‐binaphthyl(BINAP)ligands,(S)‐4,4'‐divinyl‐BINAP and(S)‐5,5'‐divinyl‐BINAP,were successfully synthesized.Chiral BINAP‐based porous organic polymers(POPs),denoted as4‐BINAP@POPs and5‐BINAP@POPs,were efficiently prepared via the copolymerization of vinyl‐functionalized BINAP with divinyl benzene under solvothermal conditions.Thorough characterization using nuclear magnetic resonance spectroscopy,thermogravimetric analysis,extended X‐ray absorption fine structure analysis,and high‐angle annular dark‐field scanning transmission electron microscopy,we confirmed that chiral BINAP groups were successfully incorporated into the structure of the materials considered to contain hierarchical pores.Ru was introduced as a catalytic species into the POPs using different synthetic routes.Systematic investigation of the resultant chiral Ru/POP catalysts for heterogeneous asymmetric hydrogenation ofβ‐keto esters revealed their excellent chiral inducibility as well as high activity and stability.Our work thereby paves a path towards the use of advanced hierarchical porous polymers as solid chiral platforms for heterogeneous asymmetric catalysis.

Effect of the Para-substituent of the Tridentate Pyridine-based Ru（II） Complex upon the Catalytic Activity in Transfer Hydrogenation

Three stable 4-substituted pyridine-based ruthenium（II）complexes[RuCl2（PPh3）L]（L=4-R-2,6-bis （diethylaminomethylene）pyridine,R=Br,H or allyloxy）were synthesized.The catalytic activities of the complexes toward transfer hydrogenation from alcohols to ketones were investigated.The electronic effects of the para-substituent in the pyridyl ring were probed and we found that the electron-donating group increased the catalytic activity.The result suggests that an electron-donating group is probably preferential for linking the catalytic ruthenium complex and the chemically inert supporting molecules such as a carbosilane dendrimer.

Effect of Diluents on the Extraction of Oxalic Acid by Trialkylphosphine Oxide

In liquid-liquid solvent extraction processes, diluents have a strong influence on the extraction mechanism and efficiency. In this study, benzene, cyclohexane, trichloromethane, carbon tetrachloride, methyl isobutyl ketone (MIBK), butyl acetate, and 1-octanol were used as diluents in the extraction of oxalic acid by trialkylphos-phine oxide (TRPO). The effects of extractant concentration, initial concentration of oxalic acid and diluent type on the extraction equilibrium partition coefficient are analyzed. The sequence of the extraction ability by different diluents is MIBK > butyl acetate > cyclohexane=benzene > carbon tetrachloride > 1-octanol > trichloromethane. Extraction mechanism was analyzed and extraction model parameters were evaluated.

Linear-regioselective hydromethoxycarbonylation of styrene using Ru-clusters/CeO2 catalyst

Hydroalkoxycarbonylation of olefins has been considered to be one of the most attractive methods to synthesize esters. Controlling the regioselectivities of linear esters(L) and branched esters(B) is a challenging project for researchers working in this reaction. Although most of the attention has been paid to control the regioselectivity through ligand design in homogeneous catalytic systems, study in the area is still limited. Herein, Ru-clusters/CeO2 is employed as a heterogeneous catalyst for the hydromethoxycarbonylation of styrene without any additives. After optimization of the reaction conditions, the conversion of styrene is > 99% with 83% and 12% regioselectivity of linear and branched ester, respectively. By using different supports(CeO2(nanoparticle), CeO2-rod, and CeO2-cube), three catalysts including Ru-clusters/CeO2, Ru/CeO2-rod, and Ru/CeO2-cube are prepared and applied in the reaction. Structural characterizations demonstrate that the L/B ratio is related to the Ru size of supported Ru catalysts. Further Raman characterization and NH3-TPD demonstrate that the metal-support interaction and the concentration of oxygen vacancy of the catalyst have a great influence on the Ru size. The mechanism and kinetic analysis for this reaction are also investigated in this work.

Hydriding/dehydriding properties of Mg-Ni-based ternary alloys synthesized by mechanical grinding

The Mg-Ni-based ternary alloys Mg2-xTixNi(x=0,0.2,0.4)and Mg2Ni1-xZrx(x=0,0.2,0.4)were successfully synthesized by mechanical grinding.The phases in the alloys and the hydriding/dehydriding properties of the alloys were investigated.Mg2Ni and Mg are the main hydrogen absorption phases in the alloys by XRD analysis.Hydriding kinetics curves of the alloys indicate that the hydrogen absorption rate increases after partial substitution of Ti for Mg and Zr for Ni.According to the measurement of pressure-concentration-isotherms and Van't Hoff equation,the relationship between ln p(H2)and 1 000/T was established.It is found that while increasing the content of correspondingly substituted elements at the same temperature,the equilibrium pressure of dehydriding increases,the enthalpy change and the stability of the alloy hydride decrease.

Determination of Boron Trifluoride in Boron Trifluoride Complex by Fluoride Ion Selective Electrode

A method was proposed to determine boron trifluoride in boron trifluoride complex using fluoride ion selective electrode(ISE). Hydroxide was chosen to mask aluminum for the determination of 0.01—0.1 mol/L of fluoride. The simulation indicated that the permissible aluminum masked at a certain p H value was limited and hardly related to F-concentration and boric acid. It is better to control p H value below 11.5 and the aluminum concentration within 0.025 mol/L to minimize the interference of hydroxide to the fluoride ISE. The decomposition conditions of boron trifluoride by aluminum chloride were investigated. It is found that the F-detection ratio will approach 1.0 if the Al/F molar ratio is 0.3—0.7 and aluminum concentration is no more than 0.02 mol/L when heated at 80 ℃ for 10 min. In one word, hydroxide is quite fit to mask aluminum for samples which contain high content of fluoride and aluminum and the BF3 content can be successfully determined by this method.

Synthesis,Structure and Electrochemistry of Triruthenium Cluster Complex [Ru_3(μ_3- O)(μ-CH_3CO_2)_6(py)_2(PPh_2py)](PF_6)·CH_2Cl_2

The reaction between [Ru3(3-O)(-CH3CO2)6(py)2(MeOH)](PF6) (py = pyri- dine) and diphenyl-2-pyridyl-phosphine (PPh2py) gave the triruthenium cluster complex [RuIII3(3-O)(-CH3CO2)6(py)2(PPh2py)](PF6)CH2Cl2 (C40H44Cl2F6N34O13P2Ru3) which was characterized by elemental analysis, IR, UV-Vis and 31P NMR spectroscopy, and X-ray single- crystal diffraction. The structure is of monoclinic, space group P21/n with a = 16.3896(1), b = 16.8773(2), c = 19.1438(2) ? b = 95.888(1), V = 5267.47(9) ?, Mr = 1324.83, Dc = 1.671 g/cm3, F(000) = 2636, m = 1.092 mm-1 and Z = 4. The final refinement gave R = 0.0508 and wR = 0.1111 for 6987 observed reflections (I > 2s(I)). Three Ru(III) atoms bridged by m3-oxo donor form an approximately isosceles triangle. The complex shows three quasireversible one- electron processes at E1/2 = 1.22 +0.03 and 1.20 V vs. Ag/AgCl.

Triangular Halogen Bond and Hydrogen Bond Supramolecular Complex Consisting of Carbon Tetrabromide, Halide, and Solvent Molecule： A Theoretical and Spectroscopic Study

The theoretical calculation and spectroscopic experiments indicate a kind of triangular three bonding supramolecular complexes CBr4…X^-…-H-C, which consist of carbon tetrabromide, halide, and protic solvent molecule （referring to dichloromethane, chloroform and acetonitrile）, can be formed in solution. The strength of halogen and hydrogen bonds in the triangular complexes using halide as common acceptor obeys the order of iodide〉bromide〉chloride. The halogen and hydrogen bonds work weak-cooperatively. Charge transfer bands of halogen bonding complexes between CBra and halide are observed in UV-Vis absorption spectroscopy in three solvents, and then the stoichiometry of 1：1, formation constants K and molar extinction coefficients ε of the halogen bonding complexes are obtained by Benesi-Hildebrand method. The K and ε show a dependence on the solvent dielectric constant and, on the whole, obey an order of iodide〉bromide〉chloride in the same solvents. Furthermore, the C-H vibrational frequencies of solvent molecules vary obviously with the addition of halide, which indicates the C-H…X- interaction. The experimental data indicate that the halogen bond and hydrogen bond coexist by sharing a common halide acceptor as predicted by calculation.