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1.
The synthesis and characterization of several new ruthenium complexes containing heterocyclic thiolate ligands are described. CpRu(PPh3)2Cl reacts with thiolate anions to give CpRu(PPh3)2SR, (1) [R = 2-mercaptobenzimidazolyl (a), 2-mercaptobenzothiazolyl (b), and 2-mercaptobenzoxazolyl (c)] in good yields. The CpRu(PPh3)-(CO)SR (2) complexes are obtained by treating (1) with CO gas in THF at room temperature. The one-pot reaction of CpRu(PPh3)2Cl, thiolate anions with chelate bisphosphine ligands (P–P), gave CpRu(P–P)SR where P–P = Ph2PCH2PPh2 (dppm) (3); Ph2PCH2CH2PPh2 (dppe) (4).  相似文献   

2.
采用密度泛函理论以及B3LYP方法和单激发组态相互作用(CIS)方法分别优化了一系列[Os(II)(CO)3(tfa)(L)](tfa为三氟乙酸; L=O^O(1), O^N(2), N^N(3), 其中O^O为六氟乙酰丙酮, O^N为羟基喹啉, N^N为3-(三氟甲基)-5-(2-吡啶基)吡唑)配合物的基态和激发态结构. 利用含时密度泛函理论(TD-DFT)结合极化连续溶剂化模型(PCM)计算了配合物在CH2Cl2溶液中的吸收和发射光谱. 研究结果表明, 优化得到的几何结构参数和相应的实验值符合得非常好, 激发态几何构型相对基态变化较小, 这与实验上观察到的较小的斯托克斯频移现象一致. 配合物1-3的最低能吸收分别在342、431和329 nm, 其磷光发射分别在521、638 和488 nm. 配合物1-3的最高占据分子轨道和最低空轨道主要表现为L配体的π和π*轨道特征, 所以它们的最低能吸收归属于π-π*电荷跃迁, 并混有少量的金属到配体的电荷跃迁(MLCT)和配体之间电荷跃迁(LLCT)微扰, 且其高能吸收也表现为配体内部(IL)和配体间(LL)的电荷跃迁. 此外, 它们的磷光发射和吸收有相似的跃迁特征.  相似文献   

3.
ZnII and CuII complexes of the ligand edampda2– [N,N-bis(pyridylmethyl)-ethylenediamine-N,N-diacetate] have been studied in solution by 1H n.m.r. and e.p.r. spectroscopies, respectively. [ZnII(edampda)] exists in solution in a major octahedral isomer (ca. 83%) in which the two carboxylate donors and two pyridylmethyl donors remain stereochemically rigid up to 333K at pD=6.0. The major octahedral complex has equivalent glycinato and pyridyl donors as shown by equivalent AB quartets for each type of chelate. By contrast, the [ZnII(edta)]2– analogue complex is known to have processes which rapidly equilibrate the coordinated carboxylates leading to coalesced, broad singlets instead of AB quartets down to 273K (freezing point of the sample). The minor [ZnII(edampda)] species has one pendant pyridylmethyl arm. The complex does not increase in abundance up to 333K via dissociation of the major species, suggesting that it possesses a different five-coordinate geometry (approximate trigonal bipyramid). The [CuII(edampda)] complex exhibits an e.p.r. spectrum that is intermediate between rhombic or tetragonal CuII complexes (near D4h) and the reversed-e.p.r. type of trigonal bipyramidal CuII complexes (ca. D3h). The single g value of 2.079 for gg>2.03 identifies the [CuII(edampda)] complex as distorted toward trigonal bipyramidal whereas its [CuII(edtaH2)(H2O)] analogue is known to be distorted toward square pyramidal. A binuclear CuI complex of edampda2– is formed only as a transient, and it rapidly disproportionates into [CuII(edampda)] and Cu metal. A mononuclear [CuI(edampda)]– complex persists for up to 8 h, but is oxidized within 3 min by O2 to the CuII complex. [CuII(edampda)] oxidizes to CuIII with a highly irreversible wave on glassy-carbon at +1.09V compared to the [NiII/III(edampda)] wave at +1.32V.  相似文献   

4.
A comparison of the electrochemical properties of a series of dinuclear complexes [M(2)(L)(RCO(2))(2)](+) with M = Mn or Co, L = 2,6-bis(N,N-bis-(2-pyridylmethyl)-sulfonamido)-4-methylphenolato (bpsmp(-)) or 2,6-bis(N,N-bis(2-pyridylmethyl)aminomethyl)-4-tert-butylphenolato (bpbp(-)) and R = H, CH(3), CF(3) or 3,4-dimethoxybenzoate demonstrates: (i) The electron-withdrawing sulfonyl groups in the backbone of bpsmp(-) stabilize the [M(2)(bpsmp)(RCO(2))(2)](+) complexes in their M(II)(2) oxidation state compared to their [M(2)(bpbp)(RCO(2))(2)](+) analogues. Manganese complexes are stabilised by approximately 550 mV and cobalt complexes by 650 mV. (ii) The auxiliary bridging carboxylato ligands further attenuate the metal-based redox chemistry. Substitution of two acetato for two trifluoroacetato ligands shifts redox couples by 300-400 mV. Within the working potential window, reversible or quasi-reversible M(II)M(III)? M(II)(2) processes range from 0.31 to 1.41 V for the [Co(2)(L)(RCO(2))(2)](+/2+) complexes and from 0.54 to 1.41 V for the [Mn(2)(L)(RCO(2))(2)](+/2+) complexes versus Ag/AgCl for E(M(II)M(III)/M(II)(2)). The extreme limits are defined by the complexes [M(2)(bpbp)(CH(3)CO(2))(2)](+) and [M(2)(bpsmp)(CF(3)CO(2))(2)](+) for both metal ions. Thus, tuning the ligand field in these dinuclear complexes makes possible a range of around 0.9 V and 1.49 V for the one-electron E(M(II)M(III)/M(II)(2)) couple of the Mn and Co complexes, respectively. The second one-electron process, M(II)M(III)? M(III)(2) was also observed in some cases. The lowest potential recorded for the E°(M(III)(2)/M(II)M(III)) couple was 0.63 V for [Co(2)(bpbp)(CH(3)CO(2))(2)](2+) and the highest measurable potential was 2.23 V versus Ag/AgCl for [Co(2)(bpsmp)(CF(3)CO(2))(2)](2+).  相似文献   

5.
Photocatalysis of biscarbonylrhenium complexes cis,trans-[Re(dmbpy)(CO)2(PR3) (PR′3)]+ (dmbpy=4,4′-dimethyl-2,2′-bipyridine: R, R′=Ph (1a +); p-FPh (1b +); R=Ph, R′=OEt (1c +); R, R′=O-i-Pr (1d +)) is reported for the first time. The rhenium complexes with two triarylphosphine ligands (1a +, 1b +) efficiently photocatalyzed CO2 reduction with triethanolamine as a sacrificial donor. On the other hand, the complexes with one or two trialkylphosphite ligand(s) (1c +, 1d +) had low photocatalytic abilities under the same reaction conditions.  相似文献   

6.
The photo-induced decarbonylation of CpCr(NO)(CO)2 (1a) in MeCN solution in the presence of R2E2 (E = S, Se; R = Me, Ph) leads to the formation of chalcogenolato-bridged binuclear complexes Cp2Cr2(NO)2(-ER)2 [E = S; R = Me (2a), Ph (3a); E = Se, R = Me (4a), Ph (5a)] while reactions between CpM(NO)(CO)2 [M = Mo (1b), W (1c)] and Ph2E2 (E = S, Se) result in mononuclear complexes CpM(NO)(EPh)2 [M = Mo; E = S (9b), Se (10b); M = W, E = S (11c), Se (12c)]. The corresponding reactions of (1b) with Me2E2 (E = S, Se) yielded both mono and binuclear complexes: CpMo(NO)(SeMe)2 (8b), Cp2Mo2(NO)2(-EMe)2 [E = S (6b), Se (7b)]. The new complexes have been characterized by i.r., 1H-, 13C-n.m.r. spectra and by electron-impact mass spectrometry.  相似文献   

7.
Electrochemical studies of the newly synthesized bis(triphenyl phosphine) ruthenium(II) complex, cis-[RuCl2(L)(PPh3)2] (1, with L = 2-(2′-pyridyl)quinoxaline, C13N3H9), were performed in acetonitrile (ACN). For this purpose, cyclic voltammograms (CVs) as well as electrochemical impedance spectra (EIS) were recorded on either glassy carbon (GC), platinum (Pt), gold (Au), or multi-walled carbon nanotube (MWCNT) electrodes. Qualitative examination of solutions of 1 in ACN was performed on the basis of conductivity measurements and electrospray ionization mass spectrometry (ESI–MS). The conductivity data suggest that 1 is a 1 : 1 type electrolyte in ACN. The ESI spectra further demonstrate that upon dissolution of 1 in ACN progressive replacement of chloro- and PPh3-ligands by ACN occurs, leading to formation of [RuCl(L)(PPh3)(CH3CN)2]+Cl?, [2 + Cl ? ]. The CVs recorded for [2 + Cl ? ] on various working electrodes demonstrate that the reversibility of the redox couple 22 +/+ enhances with the order: Au < Pt < MWCNT < GC. The EI spectra verify that GC and MWCNT electrodes provide insignificant barrier for interfacial electron transfer since they afford less charge-transfer resistance.  相似文献   

8.
Oxidative addition of XCN (X = Br, I) to Cp′Co(CO)L (L = CO, PPh3) leads to the formation of Cp′CoL(CN)X. The complexes C′pCoTCNE(L) do not react with XCN.  相似文献   

9.
Heteroligand complexes Ln(L)(iso-Bu2PS2)2(NO3) (Ln = Sm, Tb, Dy; L = Phen, 2,2??-Bipy) (I?CVI) are synthesized. The structure of Dy(Phen)(iso-Bu2PS2)2(NO3) (III) is determined from the data of X-ray structure analysis. The crystal structure of complex III is based on discrete mononuclear molecules in which the Dy atom has distorted dodecahedral coordination (polyhedron N2O2S4). The ligands Phen, iso-Bu2PS 2 ? and NO 3 ? are bidentate-cyclic. According to the X-ray diffraction analysis data, complexes I and II are isostructural to compound III. Complexes I?CVI have photoluminescence in the visible spectral range. The photoluminescence spectra of solid samples of compounds I?CVI exhibit bands corresponding to the radiative electron transitions of the Sm3+, Tb3+, and Dy3+ ions. Among the studied compounds I?CVI, the Tb(III) complexes are characterized by the most intense photoluminescence.  相似文献   

10.
The new [Pt(5)(CO)(5){Cl(2)Sn(μ-OR)SnCl(2)}(3)](3-) (R = H, Me, Et, (i)Pr; 1-4) clusters contain trigonal bipyramidal (TBP) Pt(5)(CO)(5) cores, as certified by the X-ray structures of [Na(CH(3)CN)(5)][NBu(4)](2)[1]·2CH(3)CN and [PPh(4)](3)[4]·3CH(3)COCH(3). The TBP geometry, which is rare for group 10 metals, is supported by an unprecedented interpenetration with a nonbonded trigonal prism of tin atoms. By capping all the Pt(3) faces, the Sn(II) lone pairs account for both Sn-Pt and Pt-Pt bonding, as indicated by DFT and topological wave function studies. In the TBP interactions, the metals use their vacant s and p orbitals using the electrons provided by Sn atoms, hence mimicking the electronic picture of main group analogues, which obey the Wade's rule. Other metal TBP clusters with the same total electron count (TEC) of 72 are different because the skeletal bonding is largely contributed by d-d interactions (e.g., [Os(5)(CO)(14)(PR(3))(μ-H)(n)](n-2), n = 0, 1, 2). In 1-4, fully occupied d shells at the Pt(ax) atoms exert a residual nucleophilicity toward the adjacent main group Sn(II) ions permitting their hypervalency through unsual metal donation.  相似文献   

11.
Pyrolysis a the cluster Os3(µ-H h (CO)10 (SnMe2 H) produced an as yet unidentified purple duster, which upon reaction with PEt2Ph at room temperature, gave essentially a quantitative yield of the cluster Os3(µ-H)3(CO)93-Sn) Os3(µ-H)(CO)10(PEt2Ph), 4. The X-ray structure of 4 (as the toluene solvate) shows that it consists Or two Os, triangles linked through a µ4-Sn unit, such that one of the Os3 triangle is µ3-bonded to the Sn atom (Os-Sn range 2.689(2)–2.707(2) Å) and the other is bonded via a single covalent bond (Os-Sn = 2.643(2) Å). The phosphine ligand occupies the equatorial site on a second osmium atom a be latter Os3 moiety that is syn to the Sn atom; the unique bridging hydride ligarid is believed to occupy a site that Acis to both the P and Sn atoms. Crystallographic data for compound4. 0.5C7H8: space group,P ; ca= 11862(4) Å,b = 12.940(4) Å,c = 16.513(5) Å, =68.96(3),=80.60(3)°,=62.49(2).R=0.029, 4118 observed reflections.  相似文献   

12.
The complexes [MI2(CO)3(NCMe)2] (M = Mo or W) react with one equivalent of L in CH2Cl2 at room temperature to give initially the mononuclear seven-coordinate complexes [MI2(CO)3(NCMe)L] which have been isolated for M = W; L = 3Cl-py, 3Br-py, 4Cl-py and 4Br-py. These compounds dimerise to give the iodidebridged dimers [M(μ-I)I(CO)3L]2 by displacement of acetonitrile. When M = Mo; L = 3Cl-py, 3Br-py, 4Cl-py and 4Br-py, and when M = Mo and W; L = py, 2Me-py (for M = W only), 4Me-py, 3,5-Me2-py, 2Cl-py and 2Br-py, only the dimeric complexes have been isolated. The ease of dimerisation of [MI2(CO)3(NCMe)L] is discussed in terms of the steric and electronic effects of the substituted pyridines.  相似文献   

13.
14.
Abstract

The attempt to generate the metal-phosphorus double bonded system Cp(CO)2M=PPh2 (M=Mo, W) (4a,b) via thermal or photochemical decarbonylation of Cp(CO)3M-PPh2 (la,b) leads to the formation of hydrido-phosphido-bridged complexes (μ2-H) (μ2-PPh2)[M(CO)2Cp]2 (2a,b).  相似文献   

15.
《Polyhedron》1987,6(9):1781-1784
New heterotrimetallic complexes were isolated by reaction of M(CO)3(NN)L (M = Mo, W; NN = bipy, phen; L = thioureas) either with HgX2 (X = Cl, Br, I) giving complexes of the formula [M(CO)3(NN)(X)]2Hg or with M′(CO)3(NN′)(Cl)(HgCl) (M′ = Mo, W; NN′ = bipy, phen) producing compounds of the type (Cl)(NN)(CO)3MHgM′(CO)3(NN′)(Cl). These new photosensitive substances were characterized through IR spectroscopy and conductivity measurements. Structures involving XMHgM′X bonding are proposed and the reactions are discussed in terms of an insertion of the fragment M(CO)3(NN) into the HgX bonds.  相似文献   

16.
The heteroelement-containing alkylidene imide complexes with molybdenum and tungsten Et3SiCH=Mo(NAr)(OR)2 (I), Et3 ECH=W(NAr)(OR)2 (E = Si (II), Ge (III); Ar = 2,6-i-Pr2C6H3; R=CMe2 CF3) and π-complex (RO)2(ArN)Mo(CH2=CH-GeEt3) (IV) were synthesized by the reaction of Alkyl-CH=M(NAr) (OR)2 (M=Mo, W; Alkyl = t-Bu, PhMe2C) with organosilicon and organogermanium vinyl reagents Et3ECH=CH2 (E = Si, Ge). The structure of compounds I–III was determined by X-ray diffraction (XRD). The complexes I–IV are active initiators of metathesis polymerization of cycloolefins.  相似文献   

17.
The new clusters Fe2 M(CO)103-S)(µ3-Te), I (M=W) and 2 (M=Mo) have been isolated from the room temperature reaction of Fe2(CO)6(µ-STe) andM(CO)5(THF) (M=W, Mo), respectively. Compounds1 and2 have been characterized by IR, 125 Te NMR spectroscopy, and elemental analysis. The structure of compound1 has been established by X-ray crystallography. It belongs to the triclinic space groupP witha=6.844(2) Å,b=9.397(2) Å,c=13.681(10) Å, =81.64(2)°,=81360r,=812(2)°,V=861.2(3) Å3,Z=2,D e =2.835 g cm–3. Full-matrix least-squares refinement of1 converged to R=0.043, andR w .=0.115. The structure consists of a Fe2 WSTe square pyramid and the W atom occupies the apical site of the square pyramid.  相似文献   

18.
Two new mixed metal cluster complexes PtRu3(CO)10(PPh3)(3-S)2,3 14% yield and PtRu3(CO)9(PPh3)2(3-S)2,4 23% yield were obtained from the reaction of Ru3(CO)9(3-S)2,1 with Pt(PPh3)2(C2H4) at 0°C. The cluster of4 consists of a spiked triangle of four metal atoms with two triply bridging sulfido ligands. The reaction of Ru4(CO)11(4-S)2,2 with Pt(PPh3)2(C2H4) yielded the expanded mixed-metal cluster complex PtRu4(CO)12(PPh3)(4-S)2,5 in 12% yield. The structure of the cluster5 can be described as a pentagonal bipyramid of five metal atoms and two sulfido ligands with one metal-metal bond missing. Compounds4 and5 were characterized by a single-crystal X-ray diffraction analyses.  相似文献   

19.
报导了对配合物M(bpy)2 M=Fe,Ru,Os)的量子化学密度泛函(DFT)法研究的结果.在B3LYP/LanL2DZ方法与基组的水平上进行计算 ,探讨M(bpy)32 的电子结构特征及相关性质 ,特别是中心原子对配合物的配位键长、光谱性质、电荷布居及化学稳定性等的影响规律 ,为该类配合物的合成 ,为分析光、电、催化作用机理提供理论参考.  相似文献   

20.
Heteroligand complexes Tm(L)(iso-Bu2PS2)2(NO3) (L = 2,2′-Bipy (II), Phen (III)) are synthesized. According to the X-ray phase analysis data, complex III is isostructural to mononuclear compound [Dy(Phen)(iso-Bu2PS2)2(NO3)] including, according to the X-ray diffraction data, a coordination polyhedron DyN2O2S4 (distorted dodecahedron). Single crystals of compounds [Ln(2,2′-Bipy)(iso-Bu2PS2)2(NO3)] · C6H6 (Ln = Tm (IV), Tb (V)) are obtained. An X-ray diffraction analysis shows that the crystal structures of these isostructural compounds are formed by molecules of mononuclear complexes [Ln(2,2′-Bipy)(iso-Bu2PS2)2(NO3) and uncoordinated C6H6 molecules. In complexes IV and V, the ligands [Ln(2,2′-Bipy)(iso-Bu2PS 2 ? , and NO 3 ? are bidentate-cyclic. The coordination polyhedron LnN2O2S4 is a distorted dodecahedron. Complexes II and III possess photoluminescence in the visible spectral range (λmax = 478 and 477 nm, respectively).  相似文献   

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