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1.
在乙腈溶液中, 由混合价三核锰配合物[Mn3O(ClCH2COO)6(py)2]•(H2O) (py为吡啶)与2,2′-联吡啶(bipy)反应合成了混合价(Mn3IIIMnII)四核锰配合物[Mn4O2(ClCH2COO)7(bipy)2]•H2O. 采用元素分析、红外光谱、热分析和X射线单晶衍射法确定了其组成和结构. 标题化合物晶体属于三斜晶系, 空间群P-1, 晶胞参数: a=0.89854(13) nm, b=1.4027(2) nm, c=1.9037(3) nm, α=93.518(3)°, β=96.736(3)°, γ=94.875(3)°, V=2.3680(6) nm3, Z=2, Dc=1.734 g/cm3, F(000)=1238, GOF=1.036, R1=0.0592, wR2=0.1162 [I>2σ(I)]. 在标题化合物中, 配位结构单元中心为一蝶型[Mn4(μ3-O)2]7+多核簇, 含有2个Mn3(μ3-O)单元, 具有近似C2对称轴. 4个Mn离子均为六配位, 外围配体为7个氯乙酸根和2个2,2′-联吡啶, 处于变形的八面体环境. 变温磁化率研究表明标题化合物在整体上表现为反铁磁性耦合作用, 但在低温下的磁相互作用较为复杂. 相似文献
2.
Yongjin Xu Beisheng Kang Xuetai Chen Yuanba Cai Yonghan Hu Jiaxi Lu 《Journal of Cluster Science》1992,3(2):167-177
Complex Co4mp4(Hmp)(PBu
3
n
)3 (1) (H2mp=o-Mercaptophenol) was obtained from the reaction of CoCl2 and H2mp in the presence of PBu
n
3 and NaOMe with restricted oxidation. X-ray crystallographic data: triclinic, space group
,a=15.657(5) Å,b=20.469(8) Å,c=12.383(3) Å,=93.59(3)°, =112.45(2)°, =93.65(3)°,V=3648.7 Å3,Z=2,D
c
=1.33 g/cm3;R=0.065. The molecule consists of four cobalt atoms unsymmetrically bridged by S or S and O atoms from four of the five mp ligands. The fifth mp is terminally chelated to Co(4) which is in a distorted trigonal bipyramidal geometry, while Co(1)-Co(3) are square pyramidal. Atom Co(2) is bonded to Co(1) and Co(3) (average distance 2.632 Å) with strong interactions while Co(4) is only loosely connected to Co(1) (3.402 Å) and Co(3) (2.956 Å) through oxygen bridges and a hydrogen bond. The different coordination environments O2S2P, S4P, and O4S of the cobalt atoms make the molecule highly asymmetrical. XPS fitting data confirm the difference of the Co atoms. FABMS data indicate the possible fragmentation routes. The complex is paramagnetic with eff=5.2 B. 相似文献
3.
Shao-Dong Li Feng Su Miao-Li Zhu Li-Ping Lu 《Acta Crystallographica. Section C, Structural Chemistry》2020,76(9):863-868
A new coordination polymer (CP), namely, poly[[diaquatris[μ2‐1,4‐bis(1H‐imidazol‐1‐yl)benzene]bis[μ6‐4‐(2,4‐dicarboxylatophenoxy)phthalato]tetracobalt(II)] hexahydrate], {[Co4(C16H6O9)2(C12H10N4)3(H2O)2]·6H2O}n, has been synthesized by solvothermal reaction. The CP was fully characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis, and powder and single‐crystal X‐ray diffraction. It presents a three‐dimensional (3D) structure based on tetranuclear CoII secondary building units (SBUs) with a tfz‐d net and point symbol (43)2(46·618·84). The 4‐(2,4‐dicarboxyphenoxy)phthalic acid (H4dcppa) ligands are completely deprotonated and link {Co4(COO)4}4? SBUs into two‐dimensional (2D) layers. Furthermore, adjacent layers are connected by 1,4‐bis(1H‐imidazol‐1‐yl)benzene (bib) ligands, giving rise to a 3D supramolecular architecture. Interestingly, there are numerous elliptical cavities in the CP where isolated unique discrete hexameric water clusters have been observed. The results of thermogravimetric and magnetic analyses are described in detail. 相似文献
4.
Meyer F Demeshko S Leibeling G Kersting B Kaifer E Pritzkow H 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(5):1518-1526
Pyrazolate-based dinucleating ligands with thioether-containing chelate arms have been used for the synthesis of a family of novel tetranuclear nickel(II) complexes [L2Ni4(N3)3(O2CR)](ClO4)2 that incorporate three azido bridges and one carboxylate (R = Me, Ph). Molecular structures have been elucidated by X-ray crystallography in four cases, revealing Ni4 cores with a unique topology in which two of the azido ligands adopt an unusual mu3-1,1,3 bridging mode. The compounds were further characterized by mass spectrometry, IR spectroscopy, and variable-temperature magnetic susceptibility measurements. Magnetic data analyses indicate a combination of significant intramolecular ferromagnetic and antiferromagnetic exchange interactions that give rise to an overall S(T) = 0 ground state. The sign and the magnitude of the individual couplings have been rationalized in the framework of the common magnetostructural correlations for end-to-end and end-on azido linkages, suggesting that these correlations also remain valid for the respective fragments of multiply bridging mu3-1,1,3 azido ligands. 相似文献
5.
本文报道了一个含混合多齿螯合配体的四核Mn配合物Na2[MnIII2MnII2(pdmH)2(L)2(N3)2]·2CH3OH·2H2O(1·2CH3OH·2H2O,pdmH2为2,6-吡啶二甲醇,H2L为2,6-吡啶二甲醇与2,2-二吡啶酮水合物的脱水物),并对其进行单晶结构分析、红外、元素分析和磁性研究。单晶结构分析表明,该化合物属于三斜晶系P1空间群,分子中2个Mn2+、2个Mn3+及6个来自pdmH-或L2-配体的O原子构成1个双缺口立方烷结构。磁性研究表明Mn2+与Mn3+之间为弱的反铁磁性耦合作用(J1=-0.89 cm-1,J2=-1.13 cm-1),Mn3+离子之间为稍强的铁磁性耦合作用(J3=3.20 cm-1),基态自旋值S=2,交流磁化率研究表明,在所测试条件下,其虚部没有表现出单分子磁体所具有的频率依赖现象。 相似文献
6.
A new tetranuclear cluster [Co4(bm)6Cl2]·(H2O)2·(CH3OH)(1, Hbm is(1H-benzimidazol-2-yl)-methanol) has been synthesized by solvothermal method and structurally determined by IR, elemental analysis, and single-crystal X-ray diffraction. Complex 1 belongs to monoclinic space group P21/n with a = 21.1713(5), b = 12.7948(3), c = 24.0195(9) , β = 95.309(3)°, V = 6478.6(3) 3, Z = 4, F(000) = 2568, Dc = 1.289 g·cm–3, Mr = 1257.63, μ = 9.096 mm–1, S = 1.000, the final R = 0.0861 and wR = 0.2552 for 4956 observed reflections with I 2σ(I). Two connected face-sharing cubes are observed in the framework of 1, each with one vertex missing. Complex 1 forms a 2-D network through N–H···O hydrogen bonds. The apparent holes can be observed. 相似文献
7.
通过水热合成得到了一个新颖的包含四核铜配合物的无机-有机杂化化合物[CuCl(H2O)4)][CuCl(H2O)(Phen)][{(CuPhen)2Cl2}2(bdc)]2[P2W18O62]·5H2O(1)(Phen=1,10-phenanthroline和bdc=1,4-benzenedicarboxylate),对其进行了元素分析、红外光谱、热重、电化学等表征,并用X-射线单晶衍射测定了它的晶体结构。化合物1含有由Cl和bdc桥连的四核铜配合物阳离子[{(CuPhen)2Cl2}2(bdc)]2+。此外,化合物1的电化学研究表明其对亚硝酸的还原具有很好的电催化活性。 相似文献
8.
Minggang Hu Fugui Wang Fuzhong Han Qigang Deng Wenhui Ma Hailong Yan Guohua Dong Weiming Song 《Journal of polymer science. Part A, Polymer chemistry》2017,55(12):2084-2091
A novel hydroxy‐, methoxy‐, and phenoxy‐bridge “Mitsubishi emblem” tetranuclear aluminum complex ( 1 ) is synthesized from an unsymmetric amine‐pyridine‐bis(phenol) N2O2‐ligand (H2L1) and a symmetric amine‐tris(phenol) NO3‐ligand (H2L2). Two same configuration chiral nitrogen atoms are formed in the tetranuclear Al complex upon coordination of the unsymmetric tertiary amine ligand to central Al. Complex 1 initiates controlled ring‐opening polymerization (ROP) of rac‐lactide and afford polylactide (PLA) with narrow molecular weight distributions (Mw/Mn = 1.05–1.19). The analysis of 1H NMR spectra of the oligomer indicates that the methoxy group is the initiating group and the ring‐opening polymerization of lactide follows a coordination‐insertion mechanism. The Homonuclear decoupled 1H NMR spectroscopy suggests the isotactic‐rich chains is preferentially formed in PLA. The study on kinetics of the ROP of lactide reveals the homopropagation rate is higher than the cross‐propagation rate, which is in agreement with the observed isotactic selectivity in the ROP of rac‐lactide. The stereochemistry of the polymerization was also supported by activation parameters. The introduction of unsymmetric ligand H2L1 has an effect on stereoslectivity of polymerization. This result may be of interest for the design of multinuclear metal complex catalysts containing functionalized ligands. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2084–2091 相似文献
9.
Prof. Tomoaki Tanase Miho Tanaka Mami Hamada Yuka Morita Dr. Kanako Nakamae Prof. Yasuyuki Ura Prof. Takayuki Nakajima 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(35):8219-8224
A new linear tetraphosphine containing a PNP phosphazane bridge, rac-bis[(diphenylphosphinomethyl)phenylphosphino]phenylamine (rac-dpmppan), was synthesized and utilized to support a series of Pd/Pt mixed metal tetranuclear chains, [Pd4−nPtn(μ-rac-dpmppan)2(XylNC)2](PF6)2 (XylNC=xylyl isocyanide; n=0: Pd4 ( 1 ), 1: PtPd3 ( 2 ), 2: PtPd2Pt ( 3 ), 2: Pt2Pd2 ( 4 ), 3: Pt2PdPt ( 5 )), in which the number and positions of additional Pt atoms were successfully controlled depending on the respective synthetic procedures using transformations from 1 to 3 through 2 and from 4 to 5 by redox-coupled exchange reactions. The 31P{1H} NMR and ESI mass spectra and X-ray diffraction analyses revealed almost identical tetranuclear structures, with slight contraction of metal-metal bonds according to incorporation of Pt atoms. The electronic absorption spectra of 1 – 5 exhibited characteristic bands at 635–510 nm with an energy propensity depending on the number and positions of Pt centres, which were assigned to HOMO (dσ*σσ*) to LUMO (dσ*σ*σ*) transition by theoretical calculations. The present results demonstrated that the electronic structures of Pd/Pt mixed-metal tetranuclear complexes are finely tuned as orbital-overlapping alloyed metal chains by atomically precise Pt incorporation in the Pd4 chain. 相似文献
10.
Inmaculada Escorihuela Larry R. Falvello Milagros Tomás 《Journal of Cluster Science》2004,15(4):425-435
The reaction of the tetranuclear cyanide aquo complex [{Pt(CN)4Cu(bipy)(H2O)}2]· 2H2O with aqueous ammonia produces the new tetranuclear ammino-containing product [{Pt(CN)4Cu(bipy)(NH3)}2] (1), with terminal cyanide groups and with NH3 coordinated to the Cu atom. The distorted trigonal bipyramidal coordination about copper in 1 differs from the square-pyramidal coordination present in the starting material. The bipyridine ligand in 1 is nearly perpendicular to the tetranuclear core of the molecule, as opposed to its coplanar disposition in the aquo complex. The two platinum atoms of the tetranuclear core in 1 form Pt···Pt interactions of 3. 2390(8) Å with platinum atoms of neighboring molecules, producing an echelon-shaped supramolecular chain held together by staggered (CN)4Pt···Pt(CN)4 linkages, an aggregate structure which does not have a precedent in chemistry derived from the Pt(CN)4 building block. 相似文献