担载型PtCl_2(PPh_3)_2,Pt_3(CO)_3(PPh_3)_4和Pt_4(CO)_5(PPh_3)_4催化剂的程序升温热分解的研究

用HP5988A型色谱-质谱仪的多离子选择检测器和310工程计算机系统考察了PtCl_(2-)(PPh_3)_2,Pt-3(CO)_3(PPh_3)_4和Pt_4(CO)_5(PPh_3)_4等化合物在γ-Al_2O_3,TiO_2和SiO_2载体上的程序升温热分解特性。结果表明:铂簇合物在TPDE-H_2下的脱羰基过程比TPDE-He下简单。在TPDE-H_2下,在373K能检测到单一的CO_2脱附峰,三苯基膦配体在不同载体上的分解和脱附时,苯是主要脱附产物(≥90mol％);在TPDE-He下,三苯基膦配体的分解和脱附特性同载体性质明显有关。若以脱附苯的mol％为指标,则TiO_2>γ-Al_2O_3>SiO_2。另外,在两种情况下,三苯基膦配体的分解和脱附,均因铂的存在而加速。在脱附产物中,均未发现任何含磷化合物,证明磷在铂簇合物分解后还残留在催化剂上。     

SYNTHESIS AND CHARACTERIZATION OF (PPh_3)_3Co(μ-CO)_2 V(CO)_2Cp AND (PPh_3)

ＳＹＮＴＨＥＳＩＳＡＮＤＣＨＡＲＡＣＴＥＲＩＺＡＴＩＯＮＯＦ（ＰＰｈ_３）_３Ｃｏ（μ－ＣＯ）_２Ｖ（ＣＯ）_２ＣｐＡＮＤ（ＰＰｈ_３）ＨＰｔ（μ－ＣＯ）（μ－ＰＰｈ_２）Ｖ（ＣＯ）_２ＣｐＣｈａｎｇＰｉｎｇＳＨＡＯ（ＤａｌｉａｎＩｎｓｔｉｔｕｔｅｏｆＣｈ?..     

Synthesis and Crystal Structure of {(PPh_3)_2CIRuCIRu(PPh_3) B_(10)H_8[OCH(CH_3)_2)]_2}

1INTRODUCTIONAlthoughseveralhundredpolyhedralmetallaboraneshavebeencharacterized,theincidenceofruthenaboranesisparticularlysurprising.(hThefirstpolyhedralruthenaboraneisstructurallytypifiedbythecompound[(PPh,)2RuB,,HS(OEt),j,whichisobtainedin40%yieldsfromthereactionbetweentRuCI,(PPh,),jandcloso-tB,,H,,j'--inCHCI,/EtOH.tZiWithCH,COOH/THFt'iandC,H,COOH/CH,CI,">insteadofCHCI,/EtOH,twocompoundsF{(PPh,)2Ru}~(p-MeCO,)3--(pH)z-{RuB,,H,}jand[(PPh,)2(PhCOO)RuB,,HSCljhav…     

含2-羟基吡啶负离子配体(hp~-)的铂(Ⅱ)配合物cis-PtCl(hp)(PPh_3)_2和cis-Pt(hp)_2(PPh_3)_2的结构

我们制得了两种含2-羟基吡啶负离子配体的铂(II)配合物:cis-PtCl(hp)(PPh_3)_2和cis-Pt(hp)_2(PPh_3)_2.其晶体结构测定的结果表明,两种配合物中的铂(II)离子呈近似平面的四边形配位.2-羟基吡啶负离子配体以酮式异构体形式通过氮原子配位于铂上.     

SYNTHESIS AND STRUCTURE OF trans-RuCPh_2PN(i-Bu)PPh_2]_2Cl_2

<正> The reaction of Ru(DMSO)4Cl2 and Ph2PN (i-Bu)Ph2(1:2) gave the title compound, trans-RuCPh2PN(i-Bu)PPh2]2Cl2. Crystallographic data for C56 H58Cl2N2P4Ru: triclinic, space group P1, a = 11. 575(1), b = 12. 193(3), c = 20. 297(4)A, α=75. 30(2),β=76.28(1),γ= 72. 08(2)°, V = 2596. 6(8)A3, Z = 2, Mr = 1054. 97, Dc=1. 35g/cm3,μ(MoKa) = 5. 58cm-1, F (000) = 1092; R = 0. 046 and Rw = 0. 056 for 3411 observed reflections. The Ru atom is coordinated by four P atoms and two Cl atoms, forming an octahedral configuration.     

MOLECULAR AND CRYSTAL STRUCTURE OF (μ-HOCH_2 CH_2 S)_2 Fe_2 (CO)_4(PPh_3)_2

<正> The molecular and crystal structure of the complex (μ-HOCH2CH2-S)2 Fe2(CO)4(PPh3)2 synthesized by reaction of ethylene epoxide with (μ-Lis)2Fe2(CO)6, followed by EtOH alcoholysis and PPh3 substitution,was determined by X-ray diffraction technique. The crystals are triclinic,space group P 1,with a= 10. 902(2),b=12. 106 (2),c=16. 123(4) A ,V= 2079. 36A3,α=78. 13(1),β=89. 37(2),γ=87. 93(1)°, Z = 2,Dx=1. 44 g/cm3.μ(MoKa) = 9. 149cm-1, F(000) = 940. The final R and Rw equal to 0. 055 and 0. 068,respectively,for 3598 observed independent reflections. In this molecule two PPh3 ligands are trans to the Fe - Fe bond and axially coordinated to two iron atoms. In addition,two hydroxylethyl groups are attached to bridging sulfur atoms by e-type of bond and thus this molecule is an ee conformer.     

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

1 INTRODUCTION The transition metal cluster complexes exhi- biting multistep redox processes have attracted more and more attention because of their potential applications in the areas of photonic and electronic devices[1～4]. The oxo-centered carboxyla…     

Enantioselective synthesis of (2S,2′R)-erythro-methylphenidate

A new approach towards the enantioselective synthesis of (2S,2′R)-erythro-methylphenidate (1) is described. The key step in the synthesis utilizes Evans' 4-substituted-2-oxazolidinone chiral auxiliary to control the diastereofacial selectivity in the hydrogenation of enamine intermediate 6, yielding the hydrogenated product 7 with excellent diastereoselectivity. Methanolysis of 7 afforded 1 with excellent enantiopurity.     

Synthesis, Structure and Properties of Co(NH_2CSNHNH_2)_3Cl_3·1/2HCl

The single crystal of title compound was obtained in the solution of DMF and CH3OH under the radiation of IR lamp. The crystallographic parameters obtained are as follows: trigonal system, space group P 31C, Z=4, a=b=1.0008(2) nm, c=2. 4011 nm; final R=0. 099, Rw = 0. 092. The properties of title compound were characterized by IR, UV, EPR, XPS and CV measurements.     

Syntheses and Structures of Two Ruthenium(III)Complexes [Ru(PPh_3)_2(S_2CNR_2)Cl_2]·CH_2Cl_2(R=Et and ~iPr)

Oxidation reaction of [Ru(PPh_3)_3Cl_2] with tetraethylthiuram disulfide[Et_2NCS_2]_2 or tetra-iso-pmpylthiumm disulfide[~iPr_2NCS_2]_2 afforded mthenium(Ⅲ)complexes[Ru(PPh_3)_2(S_2CNR_2)cl_2]·CH2Cl2(R=Et 1,~iPr 2)which were characterized by single-crystal X-ray diffraction.Complex 1 crystallizes in triclinic,space group Pīwith a=11.5065(6),b=12.1458(7),C=18.0034(9)(A),α=109.380(4),β=95.279(4),γ=97.969(4)°,ν=2324.8(2)(A)~3 and Z=2.Complex 2 belongs to the monoclinic system,space group P21/n with a=12.5752(3),b=20.7562(5),e=17.6821(3)(A),β=105.934(1)°,ν=4437.94(17)(A)~3 and Z=4.Both mononuclear complexes 1 and 2 have an octahedral configuration around the central ruthenium atom which is bonded to one chelated dithiocarbamate ligand,two PPh_3 ligands in mutually tram and two chlorides in mutually cis positions.The average Ru-S,Ru-P and Ru-Cl bond lengths are 2.377(2),2.412(2)and 2.369(2)(A) for 1,and 2.376(2),2.414(1)and 2.383(2)(A) for 2,respectively.The electrochemical properties of these two complexes were studied in CH_2Cl_2 solution by cyclic voltammetry.     

Sustainable and efficient 2,3-dihydroquinazolin-4(1H)-ones production over heterogeneous and recyclable Al-MCM-41 supported dual imidazolium ionic liquids nanocomposites

A type of Al-MCM-41 supported dual imidazolium ionic liquids nanocomposites have been synthesized and efficiently used as catalysts in the one-pot synthesis of 2,3-dihydroquinazolin-4(1H)-ones. It was shown that the highest efficiency was achieved in the condensation of a range of aldehydes and anthranilamide in the presence of the (2)Al-MCM-41@ILCeCl₄(0.5) solid catalyst under mild conditions. Hot filtration test confirmed that the reaction follows a heterogeneous pathway. Moreover, the catalyst was stable, very active, robust, and displayed good recyclability without significant loss of catalytic activity after five consecutive cycles during the process. Green reaction conditions, operational simplicity, feasibility, high to excellent yields, sustainability of the functionalized catalyst are the main highlights of the present protocol.     

(1S, 2S)-DPEN修饰的负载型钌-铑双金属催化剂催化苯乙酮及其衍生物的不对称加氢

制备了以三苯基膦(PPh3)作为助剂的Ru-Rh/γ-Al2O3 催化剂, 在氢氧化钾的异丙醇溶液中, 用(1S, 2S)-DPEN [(1S, 2S)-1,2-diphenylethane-1,2-diamine]作手性修饰剂对苯乙酮及其衍生物进行不对称催化加氢, 此催化剂表现出较高的催化活性和良好的对映选择性. 优化反应条件, 苯乙酮、乙基苯基酮和异丙基苯基酮的转化率分别达到92.5%, 95.9%, 100%, 生成(R)-构型产物的ee值分别达到79.6%、81.2%和81.4%.     

The effect of Pt nanoparticles distribution on the removal of cyanide by TiO2 coated Al-MCM-41 in blue light exposure

With an aim to enhance the photocatalytic activity, Pt loaded TiO₂–Al-MCM-41 catalysts with high surface area were synthesized by a multistep route. The waste of the rice processing, rice husk (RH), was used as the precursor for the extraction of silica. The diffuse reflectance and photoluminescence spectroscopy revealed the extension of the absorption edge in the visible region and exciton trapping nature of the dispersed platinum. The structural analysis was carried out by XRD, whereas X-ray photoelectron spectroscopy identified the chemical states of the components of the synthesized powders. The BET surface area measurements revealed the reduction in the surface area and pore volume with the increasing platinum loading. TEM micrographs showed the uniform distribution of TiO₂ and Pt nanoparticles at the surface of Al-MCM-41. The photocatalytic efficiency of the synthesized powders as photocatalysts was obtained for the removal of 100 ppm CN⁻ from aqueous solution in fluorescent blue light exposure. Compared to unsupported TiO₂, the Pt-loaded catalysts exhibited substantially high activity for the removal of CN⁻. A plausible mechanism for the removal of cyanide ions was proposed. The catalysts showed excellent stability and reproducibility in the successive use.     

（1S，2S）－DPEN修饰的负载型钌膦配合物催化苯乙酮及其衍生物不对称加氢反应研究

对不含官能团的简单芳香酮来说,由于除酮羰基外不具有与催化剂中心金属进行配位的辅助功能基团,因此导致钌-膦配合物催化剂对这类酮加氢的对映选择性不高[1-2].     

(1S,2S)-1,2-二苯基乙二胺修饰Ir/HAP催化苯乙酮及其衍生物的不对称加氢反应

采用浸渍法在温和条件下制备了羟基磷灰石负载的铱催化剂(Ir/HAP), 并以X射线衍射(XRD), 透射电子显微镜(TEM), X射线光电子能谱(XPS), 比表面积测定(BET)以及附带能量散射X射线谱的扫描电子显微镜(SEM-EDS)等手段对载体和催化剂进行了表征. 以(1S,2S)-1,2-二苯基乙二胺((1S,2S)-DPEN)为手性修饰剂时, 该催化剂对苯乙酮及其衍生物不对称加氢反应表现出较高活性和对映选择性(ee). 在氢气压力为3.0 MPa、303 K条件下反应3 h, 苯乙酮及其衍生物的加氢转化率在94.7%以上, 其中生成2'-(三氟甲基)苯乙醇的对映选择性高达81.5%. 在不使用其它配体作稳定剂的情况下, 该结果比目前文献报道值高. 通过对比研究发现, 羟基磷灰石作为载体优于二氧化硅等其它无机载体. 催化剂通过简单离心分离可循环使用多次, 无明显的金属铱流失.     

5,10,15,20-四羟基苯基卟啉醋酸钴在Si-MCM-41中瓶中造船法组装及表征

用瓶中造船法将5,10,15,20-四羟基苯基卟啉醋酸钴组装在Si-MCM-41中.通过ICP元素分析、DTA差热分析及XRD、EPR、XPS、UV-Vis光谱等对组装前后样品的含量、热稳定性、醋酸钴与5,10,15,20-四羟基苯基卟啉的配位情况、钴卟啉配合物在分子筛中的水热稳定性进行了研究.结果表明,醋酸钴与5,10,15,20-四羟基苯基卟啉完全能在Si-MCM-41中进行配位,配合物在Si-MCM-41中具有良好的水热稳定性及热稳定性.     

Enantioselective hydrogenation in the presence of the rhodium(i) complex with (+)-4S,5S-N4,N4,N5,N5,2,2-hexamethyl-1,3-dioxolane-4,5-dimethaneamine

Hydrogenation of -acetamidocinnamic and itaconic acids and their esters was carried out in the presence of the cationic Rh^I triflate complex with (+)-4S,5S-N ⁴,N ⁴,N ⁵,N ⁵,2,2-hexamethyl-1,3-dioxolane-4,5-dimethaneamine (DIODMA). The optical yields depended on the nature of the solvent and the hydrogen pressure and reached 30%. The catalytically active forms of the complexes and their transformations in the presence of phosphines, molecular hydrogen, and the substrate were studied by ¹H and ³¹P NMR spectroscopy.     

The Steric Effect of trans-(1S,2S)-1-Substituted-2 (N,N-dialkyl-amino)-1-indanol Derivatives as Chiral Ligands in the Catalytic Enantioselective Addition of Diethylzinc to Aldehydes

Optically active trans-(12,2S)-1-substituted-2(N,N-dialkylamino)-1-indanol derivatives have been prepared and used in the asymmetric addition of diethylzinc to aldehydes to give sec-alcohol in good yield with up to 93.1% enantiomeric excess.     

双膦配合物RuCl2(dppe)(NH2CH2CH2NH2)的合成及催化性能研究

合成了双膦配合物RuCl2(dppe)(NH2CH2CH2NH2)[dppe=1,2-二(二苯膦基)乙烷]。考察了此配合物对苯乙酮及其衍生物加氢反应的催化性能,并对各种反应参数变化对加氢反应的影响进行了详细的研究。结果表明,此配合物对苯乙酮的加氢反应具有良好的催化活性,在苯乙酮/(CH3)3COK/配合物的摩尔比为5000:40:1、氢气压力为3 MPa的条件下,于70℃反应5 h,苯乙酮的转化率可达到99.6%。     

Solvent and support effects in enantioselective hydrogenation of isophorone with (s)-α,α - diphenyl-2-pyrrolidinemethanol modified palladium

Asymmetric heterogeneous catalytic hydrogenation of isophorone has been investigated over (S)-α,α-diphenyl-2-pyrrolidinemethanol modified Pd. The influence of solvent and support effects is discussed. The impact of water, acidic and basic additives on enantioselectivity is described. This revised version was published online in June 2006 with corrections to the Cover Date.