含N4O2配体的铁(Ⅱ)配合物的合成、结构及催化烷烃氧化反应

Two iron(Ⅱ) complexes [Fe(tpdoen)](FeCl₄)Cl (2, tpdoen=N,N-bis(2-pyridylmethoxyethyl)-N-(2-pyridylmethyl)amine) and [Fe(tpdoen)](ClO₄)₂ (3) with an N₄O₂ ligand containing two potentially π-coordinate oxygen atoms were synthesized as functional models of non-heme iron oxygenases. The X-ray crystal structure analysis corroborated that complex 3 possesses a significantly distorted six-coordinate pseudooctahedral configuration, in which all six heteroatoms (N₄O₂) coordinate to the iron center. The catalytic property of complex 3 for alkane oxidation were explored using H₂O₂, TBHP and mCPBA as oxidants in the presence of excess substrates under mild conditions. When cyclohexane oxidation process was monitored by UV-Vis spectra using H₂O₂ as oxidant at 0 ℃, a short-life band appeared at ca. 550 nm, which is attributed to the in-situ Fe(Ⅲ)-OOH species. CCDC: 607630.     

冠醚化对双Schiff碱钴（Ⅱ）配合物催化氧化性能的影响

合成了冠醚化钴（Ⅱ）Ｓｃｈｉｆ碱配合物１ｃ及其相关类似物１ｂ，测定了它们的氧加合常数，考查了它们对异丙苯的催化氧化性能，并与未冠醚化的类似物１ａ作比较，讨论了１ｃ分子中的冠环对催化氧化性能的影响     

聚苯乙烯微球固载2,6-双(2-苯并咪唑)吡啶的Fe (III)配合物催化氧化活性研究

2,6-双（2-苯并咪唑）吡啶（bbp）在氯甲基化交联聚苯乙烯（CPS）微球上进行烷基化反应制得CPS-bbp,然后与FeCl₃·6H₂O进行配合得到配合物CPS-Fe（Ⅲ）-bbp.以该配合物为催化剂分别使用过氧化氢（H₂O₂）和叔丁基过氧化氢（TBHP）作氧化剂对苯乙烯、α-甲基苯乙烯和环己烯进行了催化氧化反应研究.过氧化氢氧化能力强,15 min内反应基本完成,α-甲基苯乙烯和苯乙烯的氧化产物苯乙酮和苯甲醛选择性分别高达98.49%和95.87%;TBHP的氧化缓慢而平稳,24 h后反应基本完成,对α-甲基苯乙烯和环己烯的氧化选择性较好,分别达到97.44%,和94.82%.     

Pronounced Catalytic Activity of Manganese(III)–Schiff Base Complexes in the Oxidation of Alcohols by Tetrabutylammonium Peroxomonosulfate

A novel and practical catalytic method for efficient and highly selective oxidation of a wide range of benzylic, allylic, aliphatic, primary, and secondary alcohols to the corresponding aldehydes and ketones using tetrabutylammonium peroxomonosulfate catalyzed by tetradentate Schiff base–Mn^III complexes has been developed. Electron‐deficient and hindered alcohols required longer reaction times for oxidation in this catalytic system. The electron‐poor and hindered salicylidene ring of the ligand enhanced the catalytic activity and stability of Mn catalysts. The desired turnover numbers obtained in the oxidation reactions indicated the high efficiency and relative stability of these simple Schiff base complexes in this catalytic system.     

嫁接型席夫碱配合物的制备及其催化性能

应用超声波技术在温和条件下以氯丙基三甲氧基硅烷为偶联剂, 制得了嫁接过渡金属Zn, Cu, Fe和Co的N,N-双水杨醛缩二乙烯三胺席夫碱配合物[SiO₂-M(NNOO)], 并与传统加热搅拌法制得的样品的物性和催化性能做了比较. 应用IR和UV-Vis谱学技术对其进行了初步表征, 结果表明, 两种方法制得的嫁接型配合物的红外光谱均呈现出胺基和席夫碱相应基团的特征吸收, 配体和配合物红外和紫外光谱之间的差别表明配合物结构的存在. 将所制得的样品在苯乙烯选择氧化制苯甲醛反应中进行了催化性能的测试, 考察了反应时间和催化剂对苯乙烯转化率和选择性的影响, 结果表明苯乙烯转化率均在90%以上, 苯甲醛选择性最高可达93.5%, 产物选择性与反应时间和催化剂中过渡金属的类型均有关系.     

Synthesis and magnetic properties of 3-D [Ru(II/III)(2)(O(2)CMe)(4)](3)[M(III)(CN)(6)] (M = Cr,Fe, Co)

Three-dimensional network structures of [Ru(II/III)(2)(O(2)CMe)(4)](3)[M(III)(CN)(6)] (M = Cr, Fe, Co) composition have been formed and their magnetic properties characterized. [Ru(II/III)(2)(O(2)CMe)(4)](3)[M(III)(CN)(6)] (M = Cr, Fe, Co) have nu(CN) IR absorptions at 2138, 2116, and 2125 cm(-1) and have body-centered unit cells (a = 13.34, 13.30, and 13.10 A, respectively) with -M-Ctbd1;N-Ru=Ru-Ntbd1;C-M- linkages along all three Cartesian axes. [Ru(II/III)(2)(O(2)CMe)(4)](3)[Cr(III)(CN)(6)] magnetically orders as a ferrimagnet (T(c) = 33 K) and has an unusual constricted hysteresis loop.     

Outer-Sphere Electron Transfer in Methylene Chloride: Concentration, Salt, and Temperature Dependences of the Oxidation of beta-Re(2)X(4)(cis-1,2-bis(diphenylphosphino)ethylene)(2) (X = Cl, Br) by [Co(dimethylglyoximate)(3)(BF)(2)]BF(4) and the Oxidation of Re(2)Br(4)(PMe(2)Ph)(4) by [Co(1,2-cyclohexanedione dioximate)(3)(BBu)(2)]BF(4)

The kinetics of the oxidation of beta-Re(2)X(4)(cis-1,2-bis(diphenylphosphino)ethylene)(2) (X = Cl, Br) by the cobalt clathrochelate [Co(dimethylglyoximate)(3)(BF)(2)]BF(4) and the oxidation of Re(2)Br(4)(PMe(2)Ph)(4) by the cobalt clathrochelate [Co(1,2-cyclohexanedione dioximate)(3)(BBu)(2)]BF(4) have been studied by the stopped-flow method as a function of temperature (-85 to -19 degrees C), added Bu(4)NBF(4) (0-0.100 M), and reactant concentration in the low dielectric solvent methylene chloride. For each reaction, approximately 100 different conditions were studied. The observed rate constants were well fit by a mechanism involving separate paths for free ion and the ion-paired Co(III) oxidant. The analysis yielded values for DeltaH() and DeltaS() for each path of each reaction and consistent DeltaH degrees and DeltaS degrees values for the ion-pairing of the cationic reactant and the electrolyte. In addition, temperature-dependent electrochemical measurements in 0.10 M Bu(4)NBF(4) yielded DeltaH degrees and DeltaS degrees for the electron transfer process. This is the first measurement of the homogeneous electron transfer reactivity of the dirhenium complexes, and they showed the expected high reactivity. The most notable result is a very high inhibition (ca. 700-fold) by added salt of only the [Co(dmg)(3)(BF)(2)]BF(4) reactions. We attribute this to a change of rate-controlling step, for the ion-paired path, to one involving anion migration. This appears only to occur when the magnitude of ion-pairing free energy is significantly greater than the magnitude of the free energy change for the electron transfer process.     

Synthesis and Crystal Structure of a Co(II) Complex with Schiff Base and Imidazole Ligand

1 INTRODUCTION The chemical behavior of metal complexes with Schiff base ligand has attracted much attention be- cause of their catalytic activity in some industrial[1, 2] and biochemical processes[3~5]. As some metal com- plexes have shown the catalytic activity in some polymerization reactions[2, 6], we are recently inte- rested in polymerizartion of organo-silicon com- pounds catalyzed by Schiff base complexes of tran- sition metals. A series of Schiff base complexes have been prepare…     

Versatile Catalytic Applications of Manganese(II,III) Schiff Base Complexes (Review)

Russian Journal of General Chemistry - Manganese forms a big number of complexes with Schiff bases that are extensively used as catalysts of oxidation, epoxidation, decarboxylation, coupling...     

席夫碱三核锌(II)配合物的晶体结构及荧光活性研究

以二甲基甲酰胺(DMF)为溶剂成功合成了水杨醛缩水杨酰肼席夫碱/2-氨基吡啶/锌三元混配配合物晶体, 通过测定配合物的红外、元素分析和单晶衍射等物理性质, 确定该配合物是一种三核配合物. Ｘ射线衍射实验结果表明: 标题配合物晶体属于三斜晶系, 空间群为P1, Z＝1, 分子式为Zn₃(L1)₂(2-NH₂-py)₄•0.5DMF, a＝1.15359(9) nm, b＝1.92734(15) nm, c＝2.31772(19) nm, α＝78.290(2)°, β＝78.6930(10)°, γ＝88.1090(10)°, V＝4.9478(7) nm³, D_c＝1.498 g/cm³. F(000)＝2288, μ(Mo Kα)＝1.506 mm^－1, R＝0.0449, wR＝0.0787. 同时在DMF溶液中测定了该Schiff碱及其锌配合物的荧光活性.     

丙氨酸席夫碱锰配合物催化环己烯的空气环氧化

丙氨酸席夫碱锰配合物催化环己烯的空气环氧化;分子氧     

微量热法研究Schiff碱钴配合物的抗菌活性

微量热法研究Ｓｃｈｉｆｆ碱钴配合物的抗菌活性黄在银＊屈松生冯英俞芸（武汉大学化学系武汉４３００７２）关键词二羟基苯甲醛葡萄糖Ｓｃｈｉｆ碱配合物，微量热法，抗菌活性，大肠杆菌１９９７－０８－１８收稿，１９９７－１１－０３修回国家自然科学基金及高等学校博...     

Synthesis and Structure of Heterometallic Bi(III) Complex with Diethylenetriaminepentaacetic Acid

A new heterometallic Bi(III) complex with diethylenetriaminepentaacetic acid anion (Dtpa)⁵⁻ of the composition [Co(Tsc)₃]₂[Bi(Dtpa)]₂SO⁴ ⋅ 6H₂O (I) (Tsc is thiosemicarbazide) is synthesized and its crystal structure is determined. The complex consists of the [Co(Tsc)₃]³⁺ cations, [Bi(Dtpa)]²⁻ and SO ₄ ²⁻ anions, and crystallization water molecules. The SO ₄ ²⁻ ion and two water molecules are randomly disordered over two positions. In the complex cation [Co(Tsc)₃]³⁺, the metal polyhedron has fac-form. The carboxyl groups of octadentate (Dtpa)⁵⁻ ligand in the [Bi(Dtpa)]²⁻ anion are fully deprotonated. The coordination polyhedron of the Bi atom is a distorted bicapped trigonal prism. Thermogravimetric analysis of complex I indicates that its decomposition occurs through several stages, i.e., dehydration, burning of organic ligands, and the formation of inorganic residue.__________Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 6, 2005, pp. 446–454.Original Russian Text Copyright © 2005 by Bulimestru, Petrenko, Gulea, Gdaniec, Simonov.     

Fe(bipy)(CN)(4)](-) as a versatile building block for the design of heterometallic systems: synthesis, crystal structure, and magnetic properties of PPh(4)[Fe(III)(bipy)(CN)(4)] x H(2)O, [[Fe(III)(bipy)(CN)(4)](2)M(II)(H(2)O)(4)] x 4H(2)O, and [[Fe(III)(bipy)(CN)(4)](2)Zn(II)] x 2H(2)O [bipy = 2,2'-Bipyridine; M = Mn and Zn

The new cyano complexes of formulas PPh(4)[Fe(III)(bipy)(CN)(4)] x H(2)O (1), [[Fe(III)(bipy)(CN)(4)](2)M(II)(H(2)O)(4)] x 4H(2)O with M = Mn (2) and Zn (3), and [[Fe(III)(bipy)(CN)(4)](2)Zn(II)] x 2H(2)O (4) [bipy = 2,2'-bipyridine and PPh(4) = tetraphenylphosphonium cation] have been synthesized and structurally characterized. The structure of complex 1 is made up of mononuclear [Fe(bipy)(CN)(4)](-) anions, tetraphenyphosphonium cations, and water molecules of crystallization. The iron(III) is hexacoordinated with two nitrogen atoms of a chelating bipy and four carbon atoms of four terminal cyanide groups, building a distorted octahedron around the metal atom. The structure of complexes 2 and 3 consists of neutral centrosymmetric [[Fe(III)(bipy)(CN)(4)](2)M(II)(H(2)O)(4)] heterotrinuclear units and crystallization water molecules. The [Fe(bipy)(CN)(4)](-) entity of 1 is present in 2 and 3 acting as a monodentate ligand toward M(H(2)O)(4) units [M = Mn(II) (2) and Zn(II) (3)] through one cyanide group, the other three cyanides remaining terminal. Four water molecules and two cyanide nitrogen atoms from two [Fe(bipy)(CN)(4)](-) units in trans positions build a distorted octahedron surrounding Mn(II) (2) and Zn(II) (3). The structure of the [Fe(phen)(CN)(4)](-) complex ligand in 2 and 3 is close to that of the one in 1. The intramolecular Fe-M distances are 5.126(1) and 5.018(1) A in 2 and 3, respectively. 4 exhibits a neutral one-dimensional polymeric structure containing two types of [Fe(bipy)(CN)(4)](-) units acting as bismonodentate (Fe(1)) and trismonodentate (Fe(2)) ligands versus the divalent zinc cations through two cis-cyanide (Fe(1)) and three fac-cyanide (Fe(2)) groups. The environment of the iron atoms in 4 is distorted octahedral as in 1-3, whereas the zinc atom is pentacoordinated with five cyanide nitrogen atoms, describing a very distorted square pyramid. The iron-zinc separations across the single bridging cyanides are 5.013(1) and 5.142(1) A at Fe(1) and 5.028(1), 5.076(1), and 5.176(1) A at Fe(2). The magnetic properties of 1-3 have been investigated in the temperature range 2.0-300 K. 1 is a low-spin iron(III) complex with an important orbital contribution. The magnetic properties of 3 correspond to the sum of two magnetically isolated spin triplets, the antiferromagnetic coupling between the low-spin iron(III) centers through the -CN-Zn-NC- bridging skeleton (iron-iron separation larger than 10 A) being very weak. More interestingly, 2 exhibits a significant intramolecular antiferromagnetic interaction between the central spin sextet and peripheral spin doublets, leading to a low-lying spin quartet.     

Catalytic Oxidative Decarboxylation of Some Benzylcarboxylic Acid Derivatives by a New Iron(III) Schiff Base Complex

A quadridentate Schiff base ligand of N,N’-bis(2-hydroxy-α-methylbenzylidene)ethylenediamine (HMBEDA) and its new iron(III) complex were synthesized and identified by analytical, spectral data (1H NMR, 13C NMR FT-IR and UV-visible) and molar conductance. A rapid and efficient homogeneous oxidative decarboxylation of some benzylcarboxylic acid derivatives was carried out by a catalytic amount of iron(III) Schiff base complex in chloroform, using tetrabutylammonium periodate as a mild oxidant in good to excellent yields at room temperature.     

Co(III) and Fe(III) complexes of Schiff bases derived from 2,4-dihydroxybenzaldehyde S-allyl-isothiosemicarbazonehydrobromide

Two new complexes, [Co(L¹)(Py)₃]Cl_0.75Br_0.25 (L¹=4-hydroxy salicylaldehyde S-allyl-isothiosemicarbazonato-N,N′,O) and [Fe(L²)Cl]·C₂H₅OH (L²=S-allyl-N¹-(4-hydroxy salicylaldehyde)-N⁴-(salicylaldehyde)isothiosemicarbazide-N,N′,O,O′), have been synthesized and characterized by elemental analysis, FT-IR and UV–vis spectroscopy, and molar conductivity. The solid-state structures of the complexes were also determined by single crystal X-ray diffraction. The iron(III) and cobalt(III) complexes adopt distorted square-pyramidal and octahedral geometries, respectively. The strength of the bonding in these complexes was investigated by thermogravimetric studies with both exhibiting stability with complete decomposition not occurring until ca. 600?°C.     

Alkane Oxidation with Molecular Oxygen Using a New Efficient Catalytic System: N-Hydroxyphthalimide (NHPI) Combined with Co(acac)(n)() (n = 2 or 3)

A novel class of catalysts for alkane oxidation with molecular oxygen was examined. N-Hydroxyphthalimide (NHPI) combined with Co(acac)(n)() (n = 2 or 3) was found to be an efficient catalytic system for the aerobic oxidation of cycloalkanes and alkylbenzenes under mild conditions. Cycloalkanes were successfully oxidized with molecular oxygen in the presence of a catalytic amount of NHPI and Co(acac)(2) in acetic acid at 100 degrees C to give the corresponding cycloalkanones and dicarboxylic acids. Alkylbenzenes were also oxidized with dioxygen using this catalytic system. For example, toluene was converted into benzoic acid in excellent yield under these conditions. Ethyl- and butylbenzenes were selectively oxidized at their alpha-positions to form the corresponding ketones, acetophenone, and 1-phenyl-1-butanone, respectively, in good yields. A key intermediate in this oxidation is believed to be the phthalimide N-oxyl radical generated from NHPI and molecular oxygen using a Co(II) species. The isotope effect (k(H)/k(D)) in the oxidation of ethylbenzene and ethylbenzene-d(10) with dioxygen using NHPI/Co(acac)(2) was 3.8.     

Polymer Supported Schiff Base Complexes of Iron(III), Cobalt(II) and Nickel(II) Ions and their Catalytic Activity in Oxidation of Phenol and Cyclohexene

The polymer supported transition metal complexes of N,N′‐bis (o‐hydroxy acetophenone) hydrazine (HPHZ) Schiff base were prepared by immobilization of N,N′‐bis(4‐amino‐o‐hydroxyacetophenone)hydrazine (AHPHZ) Schiff base on chloromethylated polystyrene beads of a constant degree of crosslinking and then loading iron(III), cobalt(II) and nickel(II) ions in methanol. The complexation of polymer anchored HPHZ Schiff base with iron(III), cobalt(II) and nickel(II) ions was 83.30%, 84.20% and 87.80%, respectively, whereas with unsupported HPHZ Schiff base, the complexation of these metal ions was 80.3%, 79.90% and 85.63%. The unsupported and polymer supported metal complexes were characterized for their structures using I.R, UV and elemental analysis. The iron(III) complexes of HPHZ Schiff base were octahedral in geometry, whereas cobalt(II) and nickel(II) complexes showed square planar structures as supported by UV and magnetic measurements. The thermogravimetric analysis (TGA) of HPHZ Schiff base and its metal complexes was used to analyze the variation in thermal stability of HPHZ Schiff base on complexation with metal ions. The HPHZ Schiff base showed a weight loss of 58% at 500°C, but its iron(III), cobalt(II) and nickel(II) ions complexes have shown a weight loss of 30%, 52% and 45% at same temperature. The catalytic activity of metal complexes was tested by studying the oxidation of phenol and epoxidation of cyclohexene in presence of hydrogen peroxide as an oxidant. The supported HPHZ Schiff base complexes of iron(III) ions showed 64.0% conversion for phenol and 81.3% conversion for cyclohexene at a molar ratio of 1∶1∶1 of substrate to catalyst and hydrogen peroxide, but unsupported complexes of iron(III) ions showed 55.5% conversion for phenol and 66.4% conversion for cyclohexene at 1∶1∶1 molar ratio of substrate to catalyst and hydrogen peroxide. The product selectivity for catechol (CTL) and epoxy cyclohexane (ECH) was 90.5% and 96.5% with supported HPHZ Schiff base complexes of iron(III) ions, but was found to be low with cobalt(II) and nickel(II) ions complexes of Schiff base. The selectivity for catechol (CTL) and epoxy cyclohexane (ECH) was different with studied metal ions and varied with molar ratio of metal ions in the reaction mixture. The selectivity was constant on varying the molar ratio of hydrogen peroxide and substrate. The energy of activation for epoxidation of cyclohexene and phenol conversion in presence of polymer supported HPHZ Schiff base complexes of iron(III) ions was 8.9 kJ mol^?1 and 22.8 kJ mol^?1, respectively, but was high with Schiff base complexes of cobalt(II) and nickel(II) ions and with unsupported Schiff base complexes.