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1.
2.
Two isomeric dibenzo-O2S2 macrocycles L1 and L2 have been synthesised and their coordination chemistry towards palladium(II) has been investigated. Two-step approaches via reactions of 1:1-type complexes, [cis-Cl2LPd] (1a: L = L1, 1b: L = L2), with different O2S2 macrocycle systems (L1 and L2) have led to the isolation of the following bis(O2S2 macrocycle) palladium(II) complexes in the solid state: [Pd(L1)2](ClO4)2 (2a) and a mixture of [Pd(L1)2](ClO4)2 (2a) + [Pd(L2)2](ClO4)2 (2b).  相似文献   

3.
A series of mononuclear manganese(III) complexes of formulae [Mn(L)(X)(H2O)] (1-13) and [Mn(L)(X)] (14-17) (X = ClO4, F, Cl, Br, I, NCS, N3), derived from the Schiff bases of 5-bromosalicylaldehyde and different types of diamine (1,2-diaminoethane, 1,2-diaminopropane, 1,3-diaminopropane and 1,4-diaminobutane), have been synthesized and characterized by the combination of IR, UV-Vis spectroscopies, cyclic voltammetry and by X-ray crystallography. The redox properties of all the manganese(III) complexes show grossly identical features consisting of a reversible or quasireversible MnIII/MnII reduction. Besides MnIII/MnII reduction, the complexes 4, 5, 10, 13 and 16 also show reversible or quasireversible MnIII/MnIV oxidation. A linear correlation has been found for the complexes 5, 7, 11 and 13 [Mn(L2)(X)(H2O)] (X = F, Cl, Br, I) when E1/2 [MnIII/MnII] is plotted against Mulliken electronegativities (χM). The effect of the flexibility of the ligand on redox potential has been studied. It has been observed that the manganese(II) state is stabilized with increasing flexibility of the ligand environment. The crystal structure of 6 shows an octahedral geometry.  相似文献   

4.
Two new cobalt(III) complexes of symmetric hexadentate ligand with N6 [1,10-bis(2-picolinamide)-4,7-diazadecane (pycdpnen)] and N4S2 [1,8-bis(2-picolinamide)-3,6-dithiaoctane (pycdadt)] donor set atoms have been synthesized as perchlorate salts and characterized by spectroscopic methods. All two ligands with strong-field pyridylcarboxamido N donor stabilize Co(III) as demonstrated by the facile oxidation of the cobalt center. The structures of [Co(pycdpnenH−2)](ClO4) (1) and [Co(pycdadtH−2)](ClO4) · H2O (2) investigated by COSY, HMBC, HMQC and NOESY NMR studies show that compounds 1 and 2 have the same geometrical configuration. The X-ray analysis reveals that complex 2 crystallizes in a orthorhombic space group Pccn. The cation [Co(pycdadtH−2)]+ is distorted octahedral with the two pyridyl groups in cis position.  相似文献   

5.
Reactions of (NH4)2MS4 or (NH4)2MOS3 (M = Mo, W) with AgSCN and closo carborane diphosphine ligand 1,2-(PPh2)2-1,2-C2B10H10 (L) in CH2Cl2 yielded four heterobimetallic trinuclear Mo(W)-Ag-S clusters: [Ag2MoS4L2] (1), [Ag2WS4L2] (2), [Ag2MoOS3L2] (3) and [Ag2WS4L2] (4), respectively. All the new clusters have been characterized by elemental analysis, FT-IR, UV-Vis, 1H and 13C NMR spectroscopy and their molecular structures (except for 3) were further confirmed by single-crystal X-ray diffraction. X-ray crystal structure analysis showed that the closo carborane diphosphine ligand was coordinated bidentately to Ag(I) atom through its two phosphorus atoms, resulting in a stable five-member chelating ring between the diphosphine ligand and the metal. The coordination sphere of the central M atom, as well as all the Ag atoms, was tetrahedron. The skeletons of these clusters could be classified into two types: with (NH4)2MS4, the three metal atoms (two Ag atoms and one M atom) are in a linear conformation, while with (NH4)2MOS3, the conformation of the heterobimetallic trinuclear cluster is butterfly shaped. The luminescence properties of the clusters were investigated in CH2Cl2 solution at room temperature and for the first time the butterfly-shaped Ag-W-S cluster containing the Ag2WS4 core has been proved to show luminescence property.  相似文献   

6.
Two bis(pyridyl) ligands: N,N′-bis(4-pyridyl)-1,4-benzenedicarboxamide (bpba) and N,N′-bis(3-pyridylformyl)imidazolidine-2-thione (bpit) have been designed and synthesized. Self-assembly of the linear ligand bpba and angular ligand bpit with HgI2 results in a one-dimensional zigzag polymer {[HgI2(bpba)] · 1.5CH3OH}n (1) and a binuclear metallamacrocycle [HgI2(bpit)]2 · 3H2O (2), respectively. Single crystal X-ray diffraction analyses reveal that in the crystal structure of 1 the linear ligand bpba is in transoid conformation, while in the crystal structure of 2 the angular ligand bpit coordinates with HgI2 in cisoid conformation, the different geometries of the two ligands attribute to forming the dissimilar frameworks of two HgI2 adducts. The determination of third-order nonlinear optical (NLO) properties of 1 and 2 in DMF solution shows that adducts 1 and 2 possess strong NLO self-focusing effect. The hyperpolarizability γ values of 1 and 2 are calculated to be 2.10 × 10−29 and 3.24 × 10−29 esu, respectively, which are comparable to those of some NLO materials. And the result indicates that the heavier atoms Hg and I together with the polymeric aggregation play an important role in determining their NLO properties.  相似文献   

7.
The scope of formation and structures of tungsten-iron-sulfur clusters has been explored using reactions based on [(Tp*)WS3]1− (1) as the ultimate precursor. The reaction system 1/FeCl2/NaSEt/S affords the cubane cluster [(Tp*)WFe3S4Cl3]1− (2), which with NaSEt is converted to [(Tp*)WFe3S4(SEt)3]1− (3).Clusters 2 and 3 contain the cubane [WFe33-S)4]3+ core.Complex 1 with FeCl2/NaSEt forms [(Tp*)WFe2S3Cl2(SEt)]1− (4) with the cuboidal [WFe22-S)23-S)(μ2-SR)]2+ core.Treatment of 2 with excess Et3P yields the edge-bridged double [(Tp*)2W2Fe6S8(PEt3)4] (5) with the [W2Fe63-S)64-S)2] core. Reaction of 2 with excess leads a mixture of products, from which [(Tp*)2W2Fe5S9Na(SH)(MeCN)]3−(6) was identified.This cluster, as closely related [(Tp)2Mo2Fe6S9(SH)2]3−, exhibits a core topology [W2Fe5Na(μ2-S)23-S)66-S)] very similar to the PN cluster of nitrogenase. All reactions were carried out in acetonitrile. The structures of 2-6 were established crystallographically as Et4N+ salts. In the cubane series, substitution of tungsten for molybdenum decreases the [MFe3S4]3+/2+ redox potential by ca. 0.20 V but has a negligible effect on electron distribution. This work expands the small set of previously known weak-field W-Fe-S clusters, demonstrates the existence of tungsten-containing edge-bridged double cubanes and clusters with the PN core topology, and introduces a new cuboidal core structure as found in 4 (Tp = hydrotris(pyrazolyl)borate, Tp* = hydrotris(3,5-dimethylpyrazolyl)borate).  相似文献   

8.
By using the hindered tris(pyrazolyl)borate ligand TpiPr2 (hydrotris(3,5-diisopropyl-1-pyrazolyl))borate, both mono- and binuclear complexes of cobalt [TpiPr2Co](X) (X = NO3 and OBz) and [TpiPr2Co]2(μ-X)(μ-OBz) (X = OH, N3) were synthesized. The nitrato complex, [TpiPr2Co](NO3) (1), which could be converted to (2), was prepared by reaction of KTpiPr2 with hydrated Co(NO3)2 and its molecular structure was determined by X-ray crystallography. The dinuclear di(μ-hydroxo) complex, [TpiPr2Co]2(μ-OH)2 (2), which was obtained by treatment of 1 with aqueous NaOH, reacted with one equivalent of benzoic acid to give the (μ-benzoato)(μ-hydroxo) complex, [TpiPr2Co]2(μ-OH)(μ-OBz) (3). X-ray crystallography shows the presence of both hydroxy and carboxylate group as bridging ligands and both cobalt metals are in five coordination environment in 3. The μ-azido complex, [TpiPr2Co]2(μ-N3)(μ-OBz) (5), was prepared by reaction of 3 with one equivalent of aqueous sodium azide. The spectroscopic studies suggested μ-1,1-bridging nature of group in this complex. The reaction of 2 with excess amount of benzoic acid resulted in the destruction of the bimetallic core to give the mononuclear carboxylato complex, [TpiPr2 Co](OBz) (4), which was characterized by X-ray crystallography.  相似文献   

9.
The reaction of [Ti(cp)2(BTMSA)] (1) (cp = η5-C5Me5, BTMSA = bis(trimethylsilyl)acetylene) with malonic acids ((HOOC)2CR2, R = H, Me) and N,N-dimethylglycine resulted in the formation of titanium(IV) dicarboxylato complexes [Ti(cp)2{(OOC)2CR2}] (R = H, 2; R = Me, 3) and an α-amino acid titanium(III) complex [Ti(cp)2(OOCCH2NMe2)] (4). The identities of complexes 2-4 were confirmed by microanalysis, 1H and 13C NMR spectroscopy (2, 3), ESI-MS and CID experiments (2, 3) as well as by ESR and magnetic measurements (μeff = 1.81, 298 K) for 4. Single X-ray diffraction analyses of 2 and 4 exhibited monomolecular complexes in which the titanium atom is distorted tetrahedrally coordinated by two η5-C5Me5 rings and by the chelating bound malonato-κ2O,O′ (2) and N,N-dimethylglycinato-κ2O,O′ ligand (4).  相似文献   

10.
A tridentate NNO donor Schiff base ligand [(1Z,3E)-3-((pyridin-2-yl)methylimino)-1-phenylbut-1-en-1-ol = LH] in presence of azide ions coordinates with cobalt(II) and copper(II) ions giving rise to three new coordination complexes [Co2(L)21,1-N3)2(N3)2] (1), [Cu2(L)21,3-N3)]·ClO4 (2) and [(μ1,1-N3)2Cu5(μ-OL)21,1-N3)41,1,1-N3)2]n (3). The complexes have been characterized by elemental analysis, FT-IR, UV-Vis spectral studies, and single crystal X-ray diffraction studies. These complexes demonstrate that under different synthetic conditions the azide ions and the Schiff base ligand (LH) show different coordination modes with cobalt(II) and copper(II) ions, giving rise to unusual dinuclear and polynuclear species (1, 2 and 3) whose structural variations are discussed. Magneto-structural correlation for the very rare singly μ1,3-N3 bridged CuII-Schiff base dinuclear species (2) has been studied. In addition, the catalytic properties of 1 for alkene oxidation and the general catalase-like activity behavior of 2 have been discussed.  相似文献   

11.
The 1:1 and 1:2 complexes of cis-(NH3)2PtII with 9-methyladeninium cations, 9-MeAH+, have been prepared and characterized by X-ray crystallography: cis-[(NH3)2Pt(9-MeAH-N7)Cl](NO3)2 (1) and cis-[(NH3)2Pt(9-MeAH-N7)2](NO3)4 · 2HNO3 · 2H2O (2). The pKa values for 9-MeAH+ in H2O are 1.7 in 1 as well as 0.4 (pKa1) and 1.3 (pKa2) for 2, as determined by pD dependent 1H NMR spectroscopy. Compound 2 is special in that it crystallizes with two equivalents of HNO3 per Pt entity. The HNO3 molecules are stacked in rectangular channels provided by cis-(NH3)2PtII units, 9-methyladeninium ligands and nitrate anions, which form a porous network of hydrogen bonds.  相似文献   

12.
The organotin complex [Ph3SnS(CH2)3SSnPh3] (1) was synthesized by PdCl2 catalyzed reaction between Ph3SnCl and disodium-1,3-propanedithiolate which in turn was prepared from 1,2-propanedithiol and sodium in refluxing THF. Reaction of 1 with Ru3(CO)12 in refluxing THF affords the mononuclear complex trans-[Ru(CO)4(SnPh3)2] (2) and the dinuclear complex [Ru2(CO)6(μ-κ2-SCH2CH2CH2S)] (3) in 20 and 11% yields, respectively, formed by cleavage of Sn-S bond of the ligand and Ru-Ru bonds of the cluster. Treatment of pymSSnPPh3 (pymS = pyrimidine-2-thiolate) with Ru3(CO)12 at 55-60 °C also gives 2 in 38% yield. Both 1 and 2 have been characterized by a combination of spectroscopic data and single crystal X-ray diffraction analysis.  相似文献   

13.
The reaction of aqueous cis-[Pt(NH3)2(H2O)2](NO3)2 with Na+HMEL (H2MEL, meloxicam, 4-hydroxy-2-methyl-N-(5-methyl-1,3-thiazol-2-yl)-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide), and Na+HISO (H2ISO, isoxicam, 4-hydroxy-2-methyl-N-(5-methylisoxazol-3-yl)-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide) at pH 7 produced micro-crystalline cis-[Pt(NH3)2(N1′-HMEL)2], 5 and cis-[Pt(NH3)2(N1′-HISO)2], 6. The X-ray diffraction structure of 5 shows two HMEL anions donating through the thiazole nitrogen atoms and adopting a head-to-tail (HT) conformation. The 1H NMR spectrum for 5 from DMSO-d6 shows inertness of the complex up to at least 24 h. Delivery studies for 5 and 6 from vinyl hydrogel based on l-phenylalanine (pH 6.5, 25 °C) show that concentrations of complexes ranging between 2.5 and 5 μM can be reached after a day. Compounds 5 and 6 show strong anti-proliferative effects on CH1 cells (ovarian carcinoma, human) in vitro, IC50 values being 0.60 and 0.37 μM, respectively (0.16 μM for reference, cis-diamminodichloridoplatinum(II), cisplatin). ESI-MS measurements clearly documented that both 5 and 6 form adducts with the three model proteins ubiquitin (UBI), cytochrome c (CYT C) and superoxide dismutase (SOD), the HISO complex being significantly more effective than the HMEL one. Density functional methods help in finding rationale for the easiest dissociation of Pt-H2ISO/HISO bonds when compared to the Pt-N1-H2MEL/N1-HMEL linkages.  相似文献   

14.
Synthesis and single crystal X-ray structures of H2L1 and VO(L1)(HL) [H2L1 = N,N-bis(2-hydroxy-3,5-ditertiarybutyl)-N′,N′-dimethylethylendiamine) or simply aminebis(phenol) and H2L = salicylic acid) are reported here. The complex [VO(L1)(HL)] is in distorted octahedral geometry under O4N2 donor environment where the basal core is defined by O(1), O(3), O(2) and N(5) atoms and two axial coordinates are occupied by O(4), an alkoxo-group and N(1), an imino-nitrogen atom. The electron spray mass spectrometric study on [VO(L1)(HL)] in MeCN clearly points out the existence of single species in solution. Again, the 51V NMR of the bulk polycrystalline sample reveals that the complex [VO(L1)(HL)] mainly exists in three out of four possible isomers. The formation of [VO(L1)(HL)] from both [VO(L1)(OMe)] and [VO(L1)(OEt)] was followed kinetically by reacting with salicylic acid in MeCN. The presence of isosbestic point indicates a clean conversion of the reactants to product.  相似文献   

15.
A new copper(II) complex with chloride bridges and mixed blocking ligands, [{Cu(pzPh)(Opo)}2(μ-Cl)2] (1), whereby pzPh = 3-phenyl-pyrazolyl, and OpoH = 2-hydroxypyridine-N-oxide, has been obtained by degrading tris(pyrazolyl)borate in the presence of hydrated CuCl2 salt and the ligand Opo. The molecular structure of 1 was solved by X-ray diffraction. The two Cu(II) atoms of the dinuclear complex have a pyramidal arrangement in which the two pyramids share one base-to-apex edge with parallel basal planes. Magnetic susceptibility measurements revealed ferromagnetic coupling between the Cu atoms, with J = +8.72 cm−1. X-band EPR spectra of CH2Cl2 solutions of 1 were recorded at different temperatures.  相似文献   

16.
Reaction of [(PPh2C5H4)Cp3Fe4(CO)4] (1) with (CO)4W(CH3CN)2 at ambient temperature affords [(CO)4W(PPh2C5H4)Cp3Fe4(CO)4] (2) as the major product, together with a small amount of [(CO)5W(PPh2C5H4)Cp3Fe4(CO)4] (3). Compound 3 can be obtained in good yield by treating (CO)5W(CH3CN) with equal molar of 1, and reaction of 3 with Me3NO in acetonitrile solvent produces 2 exclusively. The crystal structures of 2 and 3 have been determined by an X-ray diffraction study. Compound 2 contains an interesting μ4, η2-CO ligand, where two electrons donated by the carbon atom are involved to bridge a Fe3 face and two electrons from oxygen are donated to the tungsten(0) atom.  相似文献   

17.
A new synthetic route to the known tripodal tetradentate N3O ligand L1 (HL1 = [N-(3,5-di-tert-butyl-2-hydroxybenzyl)-N,N-di-(2-pyridylmethyl)]amine) is reported. The related compounds HLn (n = 2, 3) were prepared by a similar procedure. Treatment of HLn (n = 1-3) with FeCl3·6H2O in hot methanol led to the mononuclear iron(III) complexes [Fe(Ln)Cl2] (1: n = 1, 2: n = 2, 3: n = 3). The solid-state structures of complexes 1 and 2 were determined by X-ray crystallography. [Fe(L1)Cl2] (1) showed effective nuclease activity in the presence of hydrogen peroxide, converting supercoiled plasmid DNA to its linear form.  相似文献   

18.
The syntheses of the aliphatic bidentate guanidine-amine-hybrid ligands DMEGdmae (L1), TMGdmae (L2), TMGdeae (L3) and DPipGdmae (L4) as well as the reaction of their Cu(I) complexes with molecular oxygen (monitored by UV-Vis spectroscopy) are reported. The molecular structures of 10 bis(μ-hydroxo) dicopper complexes based on these ligands are described. The solid state structures of [Cu2(μ-OH)2(DMEGdmae)2]X2 (X = I (1), CF3SO3 (2), SbF6 (3), PF6 (4)), [Cu2(μ-OH)2(TMGdmae)2]X2 (X = I (5), CF3SO3 (6)), [Cu2(μ-OH)2(TMGdeae)2]Cu2I4 (7) and [Cu2(μ-OH)2(DPipGdmae)2]X2 (X = CF3SO3 (8), SbF6 (9), PF6 (10)) show a square-planar distorted coordination of the copper(II) ion. The bis(μ-hydroxo) dicopper complex 1 exhibits a Cu···Cu distance of 2.860(1) Å, which is one of the smallest observed for hydroxo-bridged copper compounds so far. The influence of the anion on the structure of the bis(μ-hydroxo) dicopper(II) unit is analyzed for the reported complexes and a literature overview with emphasis on the structural characteristics of the Cu2O2 moiety of bis(μ-hydroxo) dicopper(II) and bis(μ-oxo) dicopper(III) is given.  相似文献   

19.
Two alternating 1-D metal-radical linear [L:Cu(hfac)2]n and zig-zag [L:Mn(hfac)2]n chains (where L = 4-trimethylsilylethynyl-1-(4,4,5,5-tetramethyl-3-oxylimidazoline-1-oxide)benzene) and hfac = hexafluoroacetylacetonate) are described and characterized by X-ray diffraction of their crystals. Bulk magnetic measurements of L:Cu(hfac)2 indicated a ferromagnetic interaction with J = 6 cm−1 and L:Mn(hfac)2 yielded ferrimagnetic interactions with J = −95 cm−1. For the latter, a strong increase of their magnetic moment at lowest temperatures was observed only at very low static magnetic field, while for Hdc > 0.05 T saturation effect led to a downward slope after reaching a maximum.  相似文献   

20.
Reaction of CdCl2 with N-alkylaminopyrazole ligands 1-[(2-ethylamino)ethyl]-3,5-dimethylpyrazole (deae), 1-[(2-(tert-butylamino)ethyl)]-3,5-dimethylpyrazole (deat), bis-[(3,5-dimethylpyrazolyl)methyl]ethylamine (bdmae), and bis-[(3,5-dimethylpyrazolyl)ethyl]ethylamine (ddae) in absolute ethanol yields [CdCl2(NN′)] (NN′ = deae (1), deat (2)), [CdCl2(bdmae)] (3), and [CdCl(ddae)]2[CdCl4] (4). The Cd(II) complexes have been characterised by elemental analyses, conductivity measurements, IR, 1H, 13C{1H} and 113Cd NMR spectroscopies, and X-ray diffraction methods. 1H and 113Cd NMR experiments at variable temperature for 3 and 4 show that dynamic processes are taking place in solution. We report the measurements of 113Cd NMR chemical shift data for complexes 1-4 in solution. X-ray crystal structures for complexes 2 and 3 have been determined. The Cd(II) is coordinated to the deat ligand, in 2, by one nitrogen atom of the pyrazolyl group and one nitrogen atom of the amine. It finishes a tetrahedral geometry with two chlorine atoms. The bdmae ligand is linked to Cd(II), in 3, by two nitrogens atoms of the pyrazolyl groups and one amine nitrogen, along with two chlorine atoms, in a distorted trigonal bipyramidal geometry.  相似文献   

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