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Chatkaew Chailuecha Chaveng Pakawatchai Gerard A. van Albada 《Inorganica chimica acta》2006,359(13):4168-4178
Three new triply bridged dinuclear copper(II) compounds containing carboxylato bridges, [Cu2(μ-CH3COO-κ-O1,O2)2(μ-CH3COO-κ-O1)(dpyam)2](BF4) (1), [Cu2(μ-CH2CH3COO-κ-O1,O2)(μ-OH)(μ-OH2)(bpy)2](ClO4)2 (2) and [Cu2(μ-CH3COO-κ-O1,O2)(μ-OH)(μ-OH2)(phen)2](ClO4)2 (3) (in which dpyam = di-2-pyridylamine, bpy = 2,2-bipyridine, phen = phenanthroline), have been synthesized in order to investigate the magnetic super-exchange pathway between coupled copper(II) centres. All three compounds display a distorted square-pyramidal arrangement around each copper(II) ion with a CuN2O3 chromophore. Compound 1 has three acetato bridges, two of which connect each square pyramid at two equatorial sites in a triatomic bridging mode and the third acetato bridge acts at the apical site in the monoatomic bridging mode. The structures of compounds 2 and 3 are mutually similar. In each dinuclear unit, both copper(II) ions are linked at two equatorial positions through a hydroxo bridge and a triatomic carboxylato bridge and at the axial position through a water molecule.The magnetic susceptibility measurements, measured from 5 to 300 K, revealed an antiferromagnetic interaction between the Cu(II) ions in compound 1 and a ferromagnetic interaction for compounds 2 and 3 with singlet-triplet energy gaps (J) of −56, 149 and 120 cm−1, for compounds 1, 2 and 3, respectively. 相似文献
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Saranyoo Klaiklay Vatcharin Rukachaisirikul Souwalak Phongpaichit Chaveng Pakawatchai Saowanit Saithong Jirayu Buatong Sita Preedanon Jariya Sakayaroj 《Phytochemistry letters》2012,5(4):738-742
One new tetrahydroanthraquinone derivative, (2R,3S)-7-ethyl-1,2,3,4-tetrahydro-2,3,8-trihydroxy-6-methoxy-3-methyl-9,10-anthracenedione (1), together with five known anthraquinones (2–6), two known phenylethyl alcohols (7–8) and one known butanamide (9), were isolated from the mangrove-derived fungus Phomopsis sp. PSU-MA214. Their structures were established by spectroscopic evidence. Compound 1 is a rare ethyltetrahydroanthraquinone and exhibited weak cytotoxicity against breast cancer (MCF-7) cell lines and antibacterial activity against the standard Staphylococcus aureus ATCC25923 and methicillin-resistant S. aureus SK1. 相似文献
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Recent work has described the structural characterization of the complexes :dpyam:H2O (1:4:4), X′ = ClO4, BF4, ‘dpyam’ = dipyridylamine, as a pair of triclinic Z = 1 isomorphs, the cations being modelled in terms of pairs of copper atoms bridged by a carbonate ion disordered about a crystallographic inversion centre. This work has been revisited in the course of describing a new polymorph of the perchlorate in a triclinic cell of twice the size, in which the carbonate unit, now non-disordered, bridges a pair of crystallographically independent copper atoms which display distinctly different coordination environments, one close to the square-pyramidal norm, the other not. Studies of adducts of the form [(dpyam)2CuX]X′(·nH2O) are also recorded. The X/X′ = propionate/iodide adduct is found to be isomorphous with its acetate/BF4 but, interestingly, not its propionate/Cl counterpart. ‘Low’-temperature redeterminations of the NCO/Cl · 4H2O and nitrite/ClO4 adducts are also recorded, enabling definition of the hydrogen-bonding scheme in the former. 相似文献
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Sujittra Youngme Chatkaew Chailuecha Chaveng Pakawatchai Jan Reedijk 《Inorganica chimica acta》2005,358(4):1068-1078
Three new triply-bridged dinuclear copper(II) compounds with carboxylato bridges, [Cu2(μ-O2CH)(μ-OH)(μ-Cl)(dpyam)2](PF6) (1), [Cu2(μ-O2CH)2(μ-OH)(dpyam)2](PF6) (2) and [Cu2(μ-O2CCH2CH3)2(μ-OH)(dpyam)2](ClO4) (3) (dpyam = di-2-pyridylamine) have been synthesized and characterized crystallographically and spectroscopically. Compound 1 consists of a dinuclear unit in which both copper(II) ions are bridged by three different ligands, i.e., formate, chloride and hydroxide anions, providing a distorted trigonal bipyramidal geometry with a CuN2O2Cl chromophore. Compounds 2 and 3 have two bridging formato ligands and two bridging propionato ligands, respectively, together with a hydroxo bridge. The carboxylato ligands in both compounds 2 and 3 exhibit different coordination modes. One is in a syn, syn η1:η1:μ2 bridging mode and the other is in a monoatomic bridging mode. The structure of compound 2 involves a dinuclear unit, with a distorted trigonal bipyramidal geometry around each Cu(II) ion with a CuN2O3 chromophore. Compound 3 contains a non-centrosymmetric unit; the coordination environment around Cu(1) is a distorted square-pyramidal geometry and an intermediate geometry of sp and tbp around the Cu(II) ion. The Cu?Cu separations are 3.061, 3.113 and 3.006 Å for compounds 1, 2 and 3, respectively. The EPR spectra of all three compounds show a broad isotropic signal with a g value around 2.10.The magnetic susceptibility measurements, measured from 5 to 280 K, revealed a moderate ferromagnetic interaction between the Cu(II) ions with a singlet-triplet energy gap (J) of 79.7, 47.8 and 24.1 cm−1, for compounds 1, 2 and 3, respectively. Also a very weak intermolecular antiferromagnetic interaction was observed between the dinuclear units. 相似文献
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Sujittra Youngme Pongthipun Phuengphai Chaveng Pakawatchai Olivier Roubeau 《Inorganica chimica acta》2004,357(12):3603-3612
The crystal structures of two copper(II) complexes containing the ligand di-2-pyridylamine (dpyam) with monovalent H2PO4 − and divalent HPO4 2− oxoanions, [Cu(dpyam)(μ-H2PO4-O,O′)(H2PO4)]2 (1) and [Cu(dpyam)(μ3-HPO4-O,O′,O″)]n (2), are reported and determined by X-ray crystallography. The dinuclear Cu(II) complex 1 was obtained by the reaction of dpyam with Cu(NO3)2 · 3H2O and KH2PO4 in a water-ethanol (45/55) mixture. The molecules are linked into dinuclear units by two bridging didentate dihydrogenphosphate groups (endo/exo) in an equatorial-equatorial configuration giving a slightly distorted square pyramidal stereochemistry. The Cu-Cu contact distance of 5.136(2) Å is unusually large due to the exo/endo binding of the phosphate bridges. Complex 2 is a polymeric copper(II) derivative with helical [Cu(HPO4)]3 units surrounded by dpyam ligands and stabilized by intermolecular hydrogen bonds. Two nearest Cu(II) ions are bridged by a tridentate hydrogenphosphate group which is didentately coordinated to one copper(II) ion, and monodentately coordinated to another in an equatorial-equatorial configuration in an unusual bridging coordination mode. Each copper(II) ion in 2 exhibits a tetrahedrally distorted square-based geometry with the third oxygen atom (Cu-O=2.719(3) Å), from the hydrogenphosphate group weakly bound in an approximately axial position giving an extremely tetrahedrally distorted square-based pyramidal CuN2O2O′ chromophore. The magnetic susceptibility measurements (5-300 K) reveals an antiferromagnetic interaction with J values of −2.85(1) and −26.20(2) cm−1 for complexes 1 and 2, respectively. Some magneto-structural trends are discussed, along with their EPR and electronic reflectance spectra and compared with those of related complexes. 相似文献
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Sujittra Youngme Chatkaew Chailuecha Chaveng Pakawatchai Jan Reedijk 《Inorganica chimica acta》2004,357(9):2532-2542
The dihydroxo-bridged dinuclear copper(II) compound [Cu2(dpyam)2(μ-OH)2]I2 (1) and the triply bridged dinuclear copper(II) compounds with a formato bridge [Cu2(dpyam)2(μ-O2CH)(μ-OH)(μ-OMe)](ClO4) (2) and [Cu2(dpyam)2(μ-O2CH)(μ-OH)(μ-Cl)](ClO4) · 0.5H2O (3) (in which dpyam=di-2-pyridylamine) have been synthesized and their crystal structures determined by X-ray crystallographic methods. All three compounds are either centrosymmetric, or have a symmetry plane in the molecule. Compound 1 contains the [Cu2(dpyam)2(μ-OH)2]+ unit and iodide anions. Each copper(II) ion is in a slightly tetrahedrally distorted square planar coordination with the square plane consisting of two nitrogen atoms of the dpyam ligand and two bridging hydroxo groups. The Cu-I distances of 3.321 Å are quite long and only involve a weak semi-coordination. Compound 2 contains a triply bridged dinuclear copper(II) species, the coordination environment around each copper(II) ion involves a distorted trigonal-bipyramidal CuN2O3 chromophore. In the dinuclear unit of compound 3, the triply bridged copper(II) ions show a distorted trigonal-bipyramidal coordination of the CuN2O2Cl chromophore. The Cu-Cu distances are 2.933(2), 3.023(1) and 3.036(1) Å for compounds 1, 2 and 3, respectively.The magnetic susceptibility measurements, measured from 5 to 280 K, revealed a weak antiferromagnetic interaction between the Cu(II) atoms for compound 1 with a singlet-triplet energy gap (J) of −15.3 cm−1, whereas compounds 2 and 3 are ferromagnetic with J=62.5 and 79.1 cm−1, respectively. 相似文献
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