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1.
Recently, much attention has been paid to Ru(II) complexes because of their excellent properties of photochemistry, phtophysis. Bis(2,2'-bipyridine)[4-methyl-4'-(6-bromohexyl)-2,2'-bipyridine] ruthenium(II) perchlorate has been used as an active material for electrochemiluminescent (ECL) sensor for selective detection of oxalic acid.It is known that ECL efficiency of Ru(phen)32+ is much higher than that of Ru(bpy)32+. In order to make out more efficient ECL sensor, we have designed and synthesized a new Ru(II) complex, Ru(phen)2[phen-NHCO(CH2)4Br](PF6)2.  相似文献   

2.
Two mononuclear RuII complexes of polypyridyl ligands, cis-[Ru(bpy)2(4,4′-bpy)Cl](PF6)·H2O (1) and cis-[Ru(phen)2(CH3CN)2](PF6)2 (2) (bpy=2,2′-bipyridyl, 4,4′-bpy=4,4′-bipyridyl, and PHEN=1,10-phenanthroline), have been synthesized and characterized by elemental analyses, IR and UV–vis spectra. The crystal structures of both complexes have been determined by X-ray diffraction, indicating that each RuII center is hexa-coordinated (RuN5Cl for 1 and RuN6 for 2) and takes a distorted octahedral geometry. The favored feature of both complexes is that they are quite useful complex precursors for further constructing new functional architectures.  相似文献   

3.
A light-driven system consisting of tris(2,2′-bipyridine)ruthenium(II) (Ru(bpy)32+) as the photosensitizer, semicarbazide as the electron donor and molecular oxygen as the electron acceptor has been employed for hydrogen peroxide production. The efficiency of this photosystem markedly depends on pH: while the peroxide yield is almost negligible at acid, neutral or slightly alkaline pH, it reaches significant values at high hydroxide concentrations, the initial rate of H2O2 formation drastically increasing from pH 12 to pH 14. In 1 M NaOH solutions containing Ru(bpy)32+ and semicarbazide at optimum concentrations, the number of catalytic cycles (or turnover number) undergone by the ruthenium complex over the complete course of the photochemical reaction is as high as 1.1 × 104.

Spectrofluorometric and laser flash photolysis techniques were used to study the primary photochemical reactions involving the excited state of the ruthenium complex as well as the photochemically generated species Ru(bpy)33+ and Ru(bpy)3+. It is proposed that at pH 14 a sequence of reactions leading to O2 photoreduction by electrons from semicarbazide takes place, with the concomitant formation of H2O2; the excited state of Ru(bpy)32+ appears to react via oxidative quenching by oxygen rather than via reductive quenching by semicarbazide. At neutral pH, in contrast, there is no H2O2 formation owing to the fact that semicarbazide is unable to reduce (Ru(bpy)33+ to Ru(bpy)32+, although the photoexcited ruthenium complex is quenched equally by oxygen.  相似文献   


4.
A mixed-ligand monomeric complex [Zn(bpy)2(MeCO2)](ClO4)·H2O (bpy = 2,2′-bipyridine) has been prepared and characterized by X-ray crystallography. The zinc(II) atom is surrounded in a highly distorted octahedral N4O2 environment with Zn---N bonds at 2.121(5)–2.131(4) Å and Zn---O bonds at 2.155(4)–2.246(4) Å. The acetato group forms an unusual out-of-plane hydrogen bond with the lattice water molecule.  相似文献   

5.
Several new RhIII complexes, [Rh(tpy)(bpy)L](PF6)2 (tpy=2,2′:6′,2″-terpyridine, bpy=2,2′-bipyridine, and L=monoanions of phenylcyanamide(pcyd)), 4-methylphenylcyanamide (4-MePcyd), 2,4-dimethylphenylcyanamide (2,4-Me2pcyd), 4-methoxyphenylcyanamide (4-MeOPcyd), 2-chlorophenylcyanamide (2-Clpcyd) and 2,5-dichlorophenylcyanamide (2,5-Cl2pcyd) have been synthesized and characterized by elemental analysis, IR, 1H NMR and electronic absorption spectroscopies. ORTEP drawing of [Rh(tpy)(bpy)(2,5-Cl2pcyd)](PF6)2·1/2CH3CN shows three pyridyl rings of the tpy ligand that are nearly coplanar, as are the two rings of bpy. The anionic cyanamide group is coordinated end-on by the nitrile nitrogen to the RhIII. The RhIII–NCN bond is bent, having an angle of 125.4°. This bent bond is largely determined by the σ-bonding interaction of a cyanamide non-bonding electron pair in a sp2 hybrid orbital.  相似文献   

6.
Structural comparison of a new compound[(bpp)3H6]Fe2IIIFe2IIMo24V(H2PO4)8(HPO4)4(PO4)4O48(OH)12· (H2O)4·2H2O(1)[bpp=1,3-di(4-pyridyl)propane] with our previously reported two compounds[(bpy)3FeII]3· Fe2IIIFe2IIMo24V(H2PO4)8(HPO4)4(PO4)4O48(OH)12(H2O)4·12H2O(2) and[(bpy)3FeII]2FeIIFeIIIMo12V(H2PO4)2(H2-xPO4)·(H1+xPO4)(HPO4)2(PO4)2O24(OH)6(H2O)2·9H2O(x=0―1)(3)(bpy=2,2'-bipyridine), which all exhibit one-dimensional mixed-valence iron molybdophosphate anionic chains constructed by alternating connection of FeIII ions and magic[FeII(Mo6P4O31)2] units, reveals that the non-hydrogen atomic ratios of Mo:Fe:P:O within the polymeric anionic chains are the same for all the three compounds, while the polymeric anionic chains of the different compounds bear different numbers of negative charges. And therefore there exist different numbers of counter cations per {Fe2III[Fe2II(P16Mo24VO124)]} unit found in the titled compounds. It discloses that not only are the spatial assembling of counter cations and polymeric inorganic chains of three compounds quite different, but also the O―FeIII―O bond angles and FeIII―O bond lengths of the three different inorganic chains exhibit small differences. What is more important is that such small changes in bond length and bond angle in the assemblage of FeIII―O bonds lead to the considerable fluctuations of inorganic chains in their structural conformation within the three compounds, reflecting an interesting phenomenon of “flexibility" in the pure inorganic one dimensional mixed-valence iron molybdophosphate chains.  相似文献   

7.
Reaction of[Rh(H2O)6]3+ with one molar equivalent of [18]aneN2S4 in refluxing MeOH-H2O (1 : 1 v/v) for 12 h affords an orange solution from which the complex [Rh([18]aneN2S4)](PF6)3 can be isolated upon addition of NH4PF6. A single crystal X-ray structure determination shows a distorted octahedral geometry at rhodium(III) involving the four thioether and two aza-donors of the macrocycle. The complex cation adopts a rac-configuration via meridional coordination of the two SCH2CH2NCH2CH2S linkages.  相似文献   

8.
A series of chromium(III) complexes [Cr(bipy)(HC2O4)2]Cl·3H2O (1), [Cr(phen)(HC2O4)2]Cl·3H2O (2), [Cr(phen)2(C2O4)]ClO4 (3), [Cr2(bipy)4(C2O4)](SO4)·(bipy)0.5·H2O (4) and [Mn(phen)2(H2O)2]2[Cr(phen)(C2O4)2]3ClO4·14H2O (5) were synthesized (bipy=4,4′-bipyridine, phen=1,10-phenanthroline), while the crystal structures of 1 and 3–5 have been determined by X-ray analysis. 1 and 3 are mononuclear complexes, 4 contains binuclear chromium(III) ions and 5 is a 3D supromolecule formed by complicated hydrogen bonding. 1–3 are potential molecular bricks of chromium(III) building blocks for synthesis heterometallic complexes. When we use these molecular bricks as ligands to react with other metal salts, unexpected complexes 4 and 5 are isolated in water solution. The synthesis conditions and reaction results are also discussed.  相似文献   

9.
Aldehyde group-functionalized [Ru(bpy)2L](PF6)2 catalyst was prepared and immobilized onto the mesoporous silica nanoparticles to act as a heterogeneous catalyst for the selective oxidation of thioanisole to methyl phenyl sulfoxide under visible light.The heterogeneous catalyst can be easily recovered by simple centrifugation without chemical treatment,exhibiting comparable catalytic efficiency with homogeneous ones and no decrease in catalytic efficiency after at least 5 cycles.  相似文献   

10.
The reactions of M(CO)4(R′-DAB) (M = Mo) or W; R′-DAB = R′-N=CHCH=NR′ (R′ = i-propyl, t-butyl, or cyclohexyl) with SnCl4 in dichloromethane solution result in the formation, in high yield, of the orange, diamagnetic, seven-coordinate oxidative-addition products M(CO)3(R′-DAB)(SnCl3)Cl. The reactions of Mo(CO)3(R′-DAB)(SnCl3)Cl (R′ = i-Pr or Cy) with an excess of alkyl isocyanide RNC (R = CHMe2, CMe3, or C6H11) in the presence of KPF6 lead to the formation of [Mo(CNR)4(R′-DAB)Cl]PF6 or [Mo(CNR)5(R′-DAB)](PF6)2 depending upon the reaction stoichiometry and reaction conditions. The monocationic chloro species are converted to [Mo(CNR)5(R′-DAB)](PF6)2 upon reflux with the stoichiometric amount of RNC. Under similar reactions conditions M(CO)3(t-Bu-DAB)(SnCl3)Cl (M = Mo or W) derivatives react with alkyl isocyanides with the reductive-elimination of the elements of SnCl4 and the formation of octahedral M(CO)3(CNR)(t-Bu-DAB). The dark red compounds [Mo(CNCMe3)5(R′-DAB)](PF6)2 (R′ = i-Pr or Cy) react readily with cyanide ions at ambient temperatures in methanol to yield [Mo(CNCMe3)4(R′-DAB)(CN)]PF6. Attempts to thermally dealkylate the parent complexes [Mo(CNCMe3)5(R′-DAB)](PF6)2 (R′ = i-Pr or Cy) to these same cyano species were unsuccessful.  相似文献   

11.
Ruthenium(II) perchlorate complexes, [Ru(dppm)3(ClO4)]ClO4 1, [Ru(dppe)3(ClO4)]ClO4 2, and [Ru(dpae)3(ClO4)]ClO4 3, catalyse the selective homogeneous oxidation of alkenes with TBHP and H2O2 as oxidizing agents. Oxidation of cyclohexene with TBHP gave 2-cyclohexene-1-ol, 2-cyclohexenone and 1-(tert-butylperoxy)-2-cyclohexene. The homogeneous liquid phase oxidation of cyclohexene with TBHP shows appreciable solvent effect. Styrene on oxidation with TBHP gave benzaldehyde as the major product and styrene oxide as the minor product. Oxidation with H2O2 is radical-initiated and gives low conversion to products. TBHP and H2O2 are compared for their oxidizing ability and TBHP is more effective than H2O2 as an oxidizing agent. Linear and long chain alkenes are not efficiently oxidized. Cyclooctene and trans-stilbene are oxidized to the corresponding epoxides.  相似文献   

12.
Four dinuclear amino acid cadmium(Ⅱ) complexes [Cd2(tren)2(dl-alaninato)](ClO4)3·H2O(Ⅰ), [Cd2(tren)2·(l-alaninato)](ClO4)3·H2O(Ⅱ), [Cd2(tren)2(dl-phenylalaninato)](ClO4)3(Ⅲ) and [Cd2(tren)2(l-phenylalaninato)]· (ClO4)3(Ⅳ), constructed from mixed ligands of tris(2-aminoethyl)amine(tren) and racemic or natural amino acids( amino acids=dl- or l-alanine, and dl- or l-phenylalanine), have been synthesized and characterized by X-ray crystallography. The structural analysis of complexes Ⅰ and Ⅲ reveals that the cadmium centers are coordinated by one tren ligand and one amino acid molecule with the unusual (N,O,O′)-bridged mode, resulting in asymmetric chromophores of CdN4O and CdN5O in complex Ⅰ, CdN4O2 and CdN5O in complex Ⅲ, respectively. The utility of the four complexes as efficient water-compatible Lewis acid catalysts for the direct aldol reaction in water was examined. The reaction proceeded smoothly to afford the corresponding β-hydroxy ketones in up to 99% yield. Moreover, the diastereoselectivity of the reaction favors the formation of the syn-isomers.  相似文献   

13.
A pure inorganic [P2Mo5O23]6- based cobalt complex [H8(H2O)16][Co(H2O)4(HP2Mo5O23)2] with a sandglass-like shape was synthesized and characterized by means of single-crystal X-ray diffraction, powder X-ray diffraction(PXRD), infrared spectroscopy(IR), thermogravimetry/differential scanning calorimetry(TG/DSC), ultraviolet-visible spectroscopy(UV-Vis) and cyclic voltammogram(CV). Single-crystal X-ray diffraction analysis reveals that the asymmetric unit of compound 1 consists of a half cobalt ion, one [P2Mo5O23]6- anion, two coordinated water molecules and eight lattice water molecules. It is especially intriguing to note that two [P2Mo5O23]6- clusters are symmetrical about the Co ion, like a sandglass. And a chair-like water cluster with an unprecedented centrosymmetric [H8(H2O)16]8+ can be observed in compound 1. Additionally, the electrochemical and catalytic properties of compound 1 were also investigated.  相似文献   

14.
Reaction of HgSO4 with one molar equivalent of L{L = [18]aneN2S4 (1,4,10,13-tetrathia-7,16-diazacyclooctadecane) or Me2[18]aneN2S4 (7,16-dimethyl-1,4,10,13-tetrathia-7,16-diazacyclooctadecane)} in refluxing MeOH-H2O for 15 min affords a colourless solution containing the complex cation [Hg(L)]2+. Addition of excess PF6 counterion gives the complex [Hg([18]aneN2S4)](PF6)2·4/3H2O as a cream coloured solid. A single crystal X-ray structure determination shows mercury(II) bound to a severely distorted octahedral arrangement of the six macrocyclic donor atoms, Hg---S = 2.655(5), 2.735(4), 2.751(4), 2.639(5) Å, Hg---N = 2.473(11), 2.472(17) Å. The cation is in a rac configuration with the two SCH2CH2NCH2CH2S linkages bound meridionally to the metal centre.  相似文献   

15.
Reactions of [(η6-arene)RuCl2]2 (1) (η6-arene=p-cymene (1a), 1,3,5-Me3C6H3 (1b), 1,2,3-Me3C6H3 (1c) 1,2,3,4-Me4C6H2(1d), 1,2,3,5-Me4C6H2 (1e) and C6Me6 (1f)) or [Cp*MCl2]2 (M=Rh (2), Ir (3); Cp*=C5Me5) with 4-isocyanoazobenzene (RNC) and 4,4′-diisocyanoazobenzene (CN–R–NC) gave mononuclear and dinuclear complexes, [(η6-arene)Ru(CNC6H4N=NC6H5)Cl2] (4a–f), [Cp*M(CNC6H4N=NC6H5)Cl2] (5: M=Rh; 6: M=Ir), [{(η6-arene)RuCl2}2{μ-CNC6H4N=NC6H4NC}] (8a–f) and [(Cp*MCl2)2(μ-CNC6H4N=NC6H4NC)}] (9: M=Rh; 10: M=Ir), respectively. It was confirmed by X-ray analyses of 4a and 5 that these complexes have trans-forms for the ---N=N--- moieties. Reaction of [Cp*Rh(dppf)(MeCN)](PF6)2 (dppf=1,1′-bis (diphenylphosphino)ferrocene) with 4-isocyanoazobenzene gave [Cp*Rh(dppf)(CNC6H4N=NC6H5)](PF6)2 (7), confirmed by X-ray analysis. Complex 8b reacted with Ag(CF3SO3), giving a rectangular tetranuclear complex 11b, [{(η6-1,3,5-Me3C6H3)Ru(μ-Cl}4(μ-CNC6H4N=NC6H4NC)2](CF3SO3)4 bridged by four Cl atoms and two μ-diisocyanoazobenzene ligands. Photochemical reactions of the ruthenium complexes (4 and 8) led to the decomposition of the complexes, whereas those of 5, 7, 9 and 10 underwent a trans-to-cis isomerization. In the electrochemical reactions the reductive waves about −1.50 V for 4 and −1.44 V for 8 are due to the reduction of azo group, [---N=N---]→[---N=N---]2−. The irreversible oxidative waves at ca. 0.87 V for the 4 and at ca. 0.85 V for 8 came from the oxidation of Ru(II)→Ru(III).  相似文献   

16.
Three novel compounds, [Co(en)3]2[Zr2(C2O4)7]·2H20(HNU-2, en=ethylenediamine), [Co(NH3)6]· [Ce(CzO4)3(H2O)]·H2O(HNU-3) and [Co(dien)2][Gd(C2On)3]·0.75H2O(HNU-4, dien=dethylenetriamine) were hydro- thermal synthesized based on the templates of [Co(en)3]C13, [C0(NH3)6]C13 and [Co(dien)2]C13, respectively. The Zr4+ Ce3+ and Gd3+ cations are all coordinated by four oxalates to form [M(C2O4)n(H2O)n]m (M=Zr, Ce or Gd; n=0 or 1; m=4 or 5), which are similar to [In(C2O4)4]5- in NKB-1, and can be regarded as 4-connected building units. The [M(C2O4)a(H2O)n]m units are connected via sharing the bis-bidentate bridging oxalate ligands to form binuclears in HNU-2 and 1D "zigzag" chains in HNU-3 and HNU-4. cular building units to design 3D open frameworks with It is suggested that these compounds could be used as mole- zeolite topologies.  相似文献   

17.
The unique cathodic electrochemiluminescence(ECL) emission of Ru(bpy)32+(bpy=2,2′-bipyridine) was observed via Nafion film at Au electrode[Au/Nafion/Ru(bpy)32+] at about 0.20 V(vs. Ag/AgCl) and applied to the determination of several amino acids without prior derivatization with high sensitivity. The cathodic electrochemilumi-nescence(ECL) exhibits the detection limits and linear ranges of several amino acids comparable to or better than those of capillary electrophoresis with conventional ECL detection method(at 1.10—1.20 V vs. Ag/AgCl) based on precolumn derivatization. The results suggest that the cathodic ECL is promising for the detection of amino acids in bioanalysis.  相似文献   

18.
Photoluminescence (PL) and electrochemiluminescence (ECL) detection techniques are highly sensitive and widely used methods for clinical diagnostics and analytical biotechnology. In this work, a unique ruthenium(II) complex, [Ru(bpy)2(DNBSO-bpy)](PF6)2 (bpy: 2,2′-bipyridine; DNBSO-bpy: 2,4-dinitrobenzenesulfonate of 4-(4-hydroxyphenyl)-2,2′-bipyridine), has been designed and synthesized as a highly sensitive and selective PL and ECL dual-signaling probe for the recognition and detection of bio-thiols in aqueous media. As a thiol-responsive probe, the complex can specifically and rapidly react with bio-thiols in aqueous solutions to yield a bipyridine-Ru(II) complex derivative, [Ru(bpy)2(HP-bpy)]2+ (HP-bpy: 4-(4-hydroxyphenyl)-2,2′-bipyridine), accompanied by the remarkable PL and ECL enhancements. The complex was used as a probe for the PL and ECL detections of cysteine (Cys) and glutathione (GSH) in aqueous solutions. The dose-dependent PL and ECL enhancements showed good linear relationships against the Cys/GSH concentrations with the detection limits at nano-molar concentration level. Moreover, the complex-loaded HeLa cells were prepared for PL imaging of the endogenous intracellular thiols. The results demonstrated the practical utility of the complex as a cell-membrane permeable probe for PL imaging detection of bio-thiols in living cells.  相似文献   

19.
Mononuclear copper(II) complexes of a family of pyridylmethylamide ligands HL, HLMe, HLPh, HLMe3 and HLPh3, [HL = N-(2-pyridylmethyl)acetamide; HLMe = N-(2-pyridylmethyl)propionamide; HLPh = 2-phenyl-N-(2-pyridylmethyl)acetamide; HLMe3 = 2,2-dimethyl-N-(2-pyridylmethyl)propionamide; HLPh3 = 2,2,2-triphenyl-N-(2-pyridylmethyl)acetamide], were synthesized and characterized. The reaction of copper(II) salts with the pyridylmethylamide ligands yields complexes [Cu(HL)2(OTf)2] (1), [Cu(HLMe)2](ClO4)2 (2), [Cu(HL)2Cl]2[CuCl4] (3), [Cu(HLMe3)2(THF)](OTf)2 (4), [Cu(HLMe3)2(H2O)](ClO4)2 (5a and 5b), [Cu(HLPh3)2(H2O)](ClO4)2 (6), [Cu(HL)(2,2′-bipy)(H2O)](ClO4)2 (7), and [Cu(HLPh)(2,2′-bipy)(H2O)](ClO4)2 (8). All complexes were fully characterized, and the X-ray structures vary from four-coordinate square-planar, to five-coordinate square-pyramidal or trigonal-bipyramidal. The neutral ligands coordinate via the pyridyl N atom and carbonyl O atom in a bidentate fashion. The spectroscopic properties are typical of mononuclear copper(II) species with similar ligand sets, and are consistent their X-ray structures.  相似文献   

20.
Three new supramolecular networks based on paratungstate and N-donor bridging ligands, [H2bpmp]2.5H[H2W12O40]2H2O(1), [H2(bpp)]2[H(py―CH3)]0.25[H(py―C2H5)]0.25H1.5[H2W12O40]·4H2O(2) and [H2pip]3[H2W12O40](3)[bpmp=N,N'-bis(4-pyridylmethyl)piperazine; bpp=1,3-bis(4-pyridyl)propane; py=pyridine; pip=piperazine] were prepared by the hydrothermal synthesis and characterized by elemental analysis, infrared(IR), thermogravimetric(TG) analysis and single-crystal X-ray diffraction(XRD). All the compounds show high-dimen- sional supramolecular networks based on [H2W12O40]6- and the protonated N-donor ligands via the N―H···O―W hydrogen bonds and/or π···π stacking interactions. Their luminescent properties were investigated.  相似文献   

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