Mixed Carboxylate-Bridged Dimanganese(II/III) Compounds Prepared by an O2-Dependent Oxidative Cleavage of Ketones
摘要:
The structure of an O-2-sensitive Mn(II)Mn(II) complex with an unsymmetrical perchlorate bridge is reported. This complex promotes an O-2-dependent oxidative cleavage of ketones giving mixed carboxylate complexes.
一系列结构明确的双金属配合物(FeFe、NiFe、NiNi、ZnFe、NiZn)被用作分子平台来理解 Ni/Fe 协同水氧化机制。结果表明,Ni III ( μ -O)Fe IV =O 物种中桥接 O 自由基与末端 Fe IV =O 部分之间通过分子内氧-氧偶联形成 O−O 键,这为异质双金属的合理设计提供了有益的指导。催化剂。
作者:Rune Kirk Egdal、Andrew D. Bond、Christine J. McKenzie
DOI:10.1039/b901633c
日期:——
The dinuclear VIVO complex of 2,6-bis[N,N-bis(2-pyridylmethyl)amino]methyl}-4-tert-butylphenolato (bpbp−), [(VO)2bpbp(OH2)2](ClO4)3·H2O, 1 is oxidised by air. Two products have been characterised in the solid state, namely a VVVVdiperoxido complex, [(VO)2bpbp(η2-O2)2](ClO4), 2 and a VVVIVtrioxido complex, [V(O)2V(O)bpbp(OH2)](ClO4)2·2H2O·EtOH, 3. The rate of formation of 2 is solvent-dependent and
Heterodinuclear Zn(II)−Fe(III) and Homodinuclear M(II)−M(II) [M = Zn and Ni] complexes of a Bicompartmental [N 6 O] ligand as synthetic mimics of the hydrolase family of enzymes
spectrophotometric titration and the mass spectrometry studies, a monoaquated and dihydroxo species 2C, 3C and 4C has been identified as the catalytically active species responsible for the phosphodiester hydrolysis of the bis(2,4 - dinitrophenyl)phosphate (2,4 - BDNPP) substrate in the pH range 5.5-10.5. The kinetic studies further revealed that the homodinuclear [Ni(II)-Ni(II)] complexes (4) (kcat = 1.26 × 10-2 s-1)
Dinuclear iron(III)–metal(II) complexes as structural core models for purple acid phosphatases †
作者:Morten Ghiladi、Christine J. McKenzie、Anke Meier、Annie K. Powell、Jens Ulstrup、Sigrid Wocadlo
DOI:10.1039/a704388k
日期:——
(M = Zn, Cu, Ni or Co) complexes of the phenolate-hinged dinucleating ligand 2,6-bis[bis(2-pyridylmethyl)amino]methyl}-4-tert-butylphenolato(1–), bpbp– have been prepared and characterized. Both exogenous bidentate bridging groups and different terminal ligands bound to each different metal ion at the exogenous site were identified. The structure of the mixed-valence complex [(bpbp)Fe2(F)2(H2O)2][BF4]2
酚盐连接的双核配体2,6-双[双(2-吡啶基甲基)氨基]的一系列混合价铁和混合金属Fe III -M II(M = Zn,Cu,Ni或Co)配合物甲基} -4-叔丁基苯酚基(1-),bpbp –已制备并表征。鉴定了外源性双齿桥接基团和在外源性位点结合到每个不同金属离子的不同末端配体。混合价络合物[(bpbp)Fe 2(F)2(H 2 O)2 ] [BF 4 ] 2的结构证实这是在外源性桥接位点具有“非桥式”排列的单原子铰链无环双核配体的双金属配合物的罕见实例。Mössbauer光谱表明,对于高自旋铁,参数分别为ΔE Q 3.242 mm s –1,δ1.169 mm s –1和ΔE Q 0.221 mm s –1,δ0.460 mm s –1 2+和高自旋Fe 3+离子。[(bpbp)Fe 2(F)2(H 2 O)2 ] [BF 4 ] 2 ·4H 2的晶体O是三斜晶系,空间群P(编号2),a
Tunability of the MIIMIII/MII2 and MIII2/MIIMIII (M = Mn, Co) couples in bis-μ-O,O′-carboxylato-μ-OR bridged complexes
作者:Rune Kirk Seidler-Egdal、Frank B. Johansson、Sune Veltzé、Eivind M. Skou、Andrew D. Bond、Christine J. McKenzie
DOI:10.1039/c0dt01552k
日期:——
their MII2 oxidation state compared to their [M2(bpbp)(RCO2)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 redoxchemistry. Substitution of two acetato for two trifluoroacetato ligands shifts redox couples by 300–400 mV. Within the working potential window, reversible
Dicobalt II−II, II−III, and III−III Complexes as Spectroscopic Models for Dicobalt Enzyme Active Sites
作者:Frank B. Johansson、Andrew D. Bond、Ulla Gro Nielsen、Boujemaa Moubaraki、Keith S. Murray、Kevin J. Berry、James A. Larrabee、Christine J. McKenzie
DOI:10.1021/ic7020534
日期:2008.6.1
geometries of the complexes are very similar, with minor variations in metal-ligand bond distances consistent with oxidation state assignments. The CoIICoIII compound is a valence-trapped Robin-Day class II complex. Solid state 31P NMR spectra of the diamagnetic CoIIICoIII (3) and paramagnetic CoIICoIII (2) and CoIICoII (1) complexes show that 31P isotropic shifts broaden and move downfield by about 3000 ppm