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11.
The mixed complex [Ni(L)(L')](ClO4)2 has been synthesized using 2-aminoethyl- bi(3-bi-aminopropyl)amine with phen (1,10-phenanthroline) in the presence of Ni(II) ion, and its structure was determined by X-ray diffraction. The crystal crystallizes in monoclinic, space group P21/c with a = 13.713(2), b = 13.1466(19), c = 14.780(2) (A), β = 97.620(3)°, V = 2640.9(7)(A)3, F(000) = 1272, Z = 4, Dc = 1.540 g/cm3, R = 0.0536 and wR = 0.1207. The Ni2+ ion is six- coordinated to furnish a distorted octahedral geometry. 相似文献
12.
Dr. Atsuko Masuya-Suzuki Satoshi Goto Takafumi Kambe Dr. Ryunosuke Karashimada Dr. Yasuhiro Kubota Prof. Nobuhiko Iki 《ChemistryOpen》2021,10(1):46-55
We prepared Ln(III) (Ln=Eu, Gd, and Yb) complexes with a tripodal Schiff base, tris[2-(5-methylsalicylideneimino)ethyl]amine (H3L) and studied their photophysical properties. Upon ligand excitation, YbL showed Yb(III)-centered luminescence in the near-infrared region. While the overall quantum yield (0.60(1)%) of YbL in acetonitrile was moderate among the reported values for Yb(III) complexes, its radiative lifetime (0.33(2) ms) was significantly shorter than those reported previously. We propose that the ligand-to-metal charge-transfer (LMCT) state mediated the sensitization in YbL. The emission and excitation spectra of EuL indicated the participation of the LMCT state in the sensitization. The radiative lifetime (0.84(7) ms) for EuL in the solid state was rather short compared to those of reported Eu(III) complexes. Our results show that the Yb(III) complex with the Schiff base ligand has two features: the short radiative lifetime and the non-triplet sensitization path. 相似文献
13.
设计、合成了一种新颖的三角架结构罗丹明B衍生物(2).在乙醇-水(8/1,V/V)介质中,用Tris-HCl控制体系pH为6.8,观察到Cu^2+对化合物2的荧光及紫外-可见吸收增强性能,同时化合物2对Cu^2+具有较高的选择性响应.选择最大激发和发射波长为557/577nm,测定了探针2(1.00×10^-5mol·L^-1)对Cu^2+响应的校准曲线,线性范围为0.10~10.00×10^-5mol·L^-1,相关系数R^2=0.9964(n=15),检出限为1.129×10^-7mol·L^-1,平行测定5次的相对标准偏差(R.S.D.)为2.2%;以557nm为最大吸收波长测定紫外吸收,Cu^2+响应的浓度线性范围为0.50~25.00×10^-5mol·L^-1,相关系数R^2=0.9948(n=13),检出限为3.338×10^-7mol·L^-1. 相似文献
14.
Twelve ruthenium(III) complexes bearing amine-bis(phenolate) tripodal ligands of general formula [Ru(L1–L3)(X)(EPh3)2] (where L1–L3 are dianionic tridentate chelator) have been synthesized by the reaction of ruthenium(III) precursors [RuX3(EPh3)3] (where E = P, X = Cl; E = As, X = Cl or Br) and [RuBr3(PPh3)2(CH3OH)] with the tripodal tridentate ligands H2L1, H2L2 and H2L3 in benzene in 1:1 molar ratio. The newly synthesized complexes have been characterized by analytical (elemental and magnetic susceptibility) and spectral methods. The complexes are one electron paramagnetic (low-spin, d5) in nature. The EPR spectra of the powdered samples at RT and the liquid samples at LNT shows the presence of three different ‘g’ values (gx ≠ gy ≠ gz) indicate a rhombic distortion around the ruthenium ion. The redox potentials indicate that all the complexes undergo one electron transfer process. The catalytic activity of one of the complexes [Ru(pcr-chx)Br(AsPh3)2] was examined in the transfer hydrogenation of ketones and was found to be efficient with conversion up to 99% in the presence of isopropanol/KOH. 相似文献
15.
Copperproteinsitesareassociatedwithavarietyofvitalbiologicalfunctions,includingelectrontransfer,anddioxygentransportandactivationl.ThelargemolecularweightandcomPlexnatureoftheproteinsmakedetailedstudiesoftheiractivesitesandchemistryverydifficult-Tobetterunderstandtheinherentcoordinationchemistryassociatedwiththeactivesite,syntheticanalogsaremostuseful2.Histidine(imidazole)playskeyrolesinthecatalyticfunctionsofalmostallofthemetalloenzymes.Therefore,complexeswithinddazoleligandsareofinterestast… 相似文献
16.
Philip J. Bailey Dr. Laura Budd Dr. Filipa A. Cavaco Simon Parsons Prof. Felix Rudolphi Alejandro Sanchez‐Perucha Dr. Fraser J. White Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(9):2819-2829
The dimethylamine in the adducts [(HNMe2)B(azolyl)3] (azolyl=methimazolyl, pyrazolyl), obtained by reaction of the azole with B(NMe2)3, can readily be substituted with a range of nitrogen donors to provide new charge‐neutral, tripodal ligands in high yield. This observation has led to a revision of an earlier interpretation of the mechanism of the formation of these species. The donor properties of the ligands [(nmi)B(azolyl)3] (nmi=N‐methylimidazole) have been compared with their anionic analogues [HB(azolyl)3]? by synthesis of their manganese(I)–tricarbonyl complexes and comparison of their infrared νCO energies. This comparison indicates that the new neutral ligands are only marginally weaker donors than the corresponding anionic hydrotris(azolyl)borate ligands. This may be explained by the ability of the attached nmi ring to stabilize a positive charge remotely from the coordinated metal, which may also account for the fact that the [(nmi)B(pyrazolyl)3] ligand is a substantially stronger donor than the similarly neutral tris(pyrazolyl)methane ligand. 相似文献
17.
LI Na MA Cheng-Bing WANG Mei ZHOU Rong-Wei HU Ming-Qiang CHEN Chang-Neng 《结构化学》2010,29(11):1731-1735
A new manganese compound [Mn8(tmp)2(Htmp)4((CH3)3CCO2)4(py)2Cl2]·2py (1·2py, H3tmp = 1,1,1-tri(hydroxymethyl)propane, py = pyramid) has been synthesized and its structure was characterized by IR, elemental analysis and X-ray diffraction. Compound 1 belongs to the triclinic system, space group P1 with a = 13.378(5), b = 14.334(5), c = 15.012(6) , α = 107.637(5), β = 95.635(3), γ = 92.825(4)°, V = 2720.7(17) 3, Z = 1, C76H124N4O26Cl2Mn8, Mr = 2022.23, Dc = 1.234 Mg/m3, μ = 1.007 mm-1, F(000) = 1052, T = 293(2) K, the final R = 0.0755 and wR = 0.2163 for all 6463 observed reflections (I > 2σ(I)). X-ray analysis shows that the core of 1 contains a [Mn8] mixed-valence rod-like unit consisting of six edge-sharing triangles (Mn3), each of which is bridged by a μ3-oxygen atom. 相似文献
18.
Luke J. Batchelor Emma Fitzgerald Dr. Joanna Wolowska Dr. Joseph J. W. McDouall Prof. Eric J. L. McInnes 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(36):11082-11088
The synthesis, structural and magnetic characterisation of [VIII3O(tmme)2(diimine)2Cl] [diimine=2,2′‐bipyridine ( 1 ) or 1,10‐phenanthroline ( 2 )] and (HNEt3)2[VIII4O(tmme)4] ( 3 ) is reported, in which H3tmme is tris(mercaptomethyl)ethane, MeC(CH2SH)3, the thiol analogue of the famous tripodal alcohol ligands typified by H3thme [tris(hydroxymethyl)ethane, MeC(CH2OH)3]. Complexes 1 and 3 have “T‐shaped” and square topologies, respectively, and the latter is centred on a rare example of a square‐planar oxide. The tri‐thiolate ligands bind the periphery of the clusters and provide such strong antiferromagnetic exchange pathways that in both cases only a single total spin state is occupied up to room temperature, in the absence of metal–metal bonding. Magnetic data, electronic structure calculations and electrochemical data are reported. 相似文献
19.
From a comparativereview on the two title series of compounds, the first part of the paper describes the most salient structural and reactivity properties
of these trimetallic complexes, including metal-metal bond formation, conformational changes, enantio, and diastereomorphism.
The second part presentsnew results which extend the comparison to a series of trimetallatrioxo adamantane complexes. The single crystal X-ray diffraction of
the parent compound [Rh3{μ
3−(OCH2)3CCH3}(CO)6]—a derivative of the commercially available tripod ligand 1,1,1tris (oxomethyl)ethane—is reported together with its crystal packing which is compared to that of its sulfido analog. The paper
includes a discussion of the nucleophilic and electrophilic properties of the trimetalla trioxo adamantane rhodium complexes,
based on semi-empirical extended Hückel calculations
Dedicated to Professor Yves Jeannin on the occasion of his 65 th birthday. 相似文献
20.
Lang Tao SHEN Ting YANG Hong Yu LI Ji HU Zhi Fu LUO National Isotope Center of Engineering Technology China Institute of Atomic Energy Beijing P. O. Box 《中国化学快报》2006,(6)
Iron is indispensable for almost all life forms1. Under iron-deficient environments, microorganisms secrete siderophores to chelate ferric ions and then, transport ferric ions into cells by specific receptor recognitions2,3. Siderophores have many clinica… 相似文献