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1.
Two nickel(II) isothiosemicarbazone complexes of dianionic 5-bromosalicylaldehyde S-allyl isothiosemicarbazonehydrobromide (H2L.HBr), [Ni(Im)L] and [Ni(2-MeIm)L] (Im: imidazole, 2-MeIm: 2-methylimidazole), were synthesized and characterized by single crystal X-ray crystallography, 1H NMR spectrometry, IR, and electronic spectroscopy. The complexes have square-planar geometry and the ligand is coordinated as a dinegative tridentate chelating agent via phenolic oxygen, isothioamide nitrogen, and azomethine nitrogen atoms. To complement the experimental data, density functional theory (DFT) and time-dependent DFT methods were used to validate the structural parameters and infrared and electronic spectra.  相似文献   

2.
Platinum(IV) halides formed complexes of the type PtL2X4 [L=1-vinyl imidazole (1,-VIm), 1-methylimidazole (1-MeIm), 1,2-dimethylimidazole (1,2-Me2Im), 1-vinyl-2-methylimidazole (1-V-2-MeIm), 2-methylimidazole (2-MeIm), 2-ethylimidazole (2-EtIm), 2-isopropylimidazole (2-i-PrIm), and 4-methylimidazole (4-MeIm); X=Cl, Br] in neutral aqueous solution. The 1-n-butylimidazole (1-n-BuIm) ligand yielded only (LH)2PtX6 compound in the same medium. The compounds were characterised by elemental analyses, IR, UV-VIS and 1HNMR spectra.  相似文献   

3.
Summary Reaction of ruthenium(III) chloride with imidazole(Im) and different substituted imidazoles,viz. N-methylimidazole (N-MeIm), 2-methylimidazole(2-MeIm), 4-methylimidazole (4-MeIm),N-vinylimidazole(N-VIm), 2-methyl- 1-vinyl-imidazole(2-Me-1-VIm), 1,2-dimethylimidazole(1,2-Me,Im), 2-ethylimidazole(2-EtIm) and 2-ethyl-4(5)-methylimidazole (2-Et-4(5)-MeIm] yield products of the types [Ru2L4Cl6] · 2 H2O (L = N-VIm or 4-MeIm), [Ru2L4Cl6] · 4 H2O (L = Im or 2-Et-4(5)-MeIm), [Ru2L 3 (H2O)Cl6] (L =N-MeIm or 2-MeIm), [Ru2L 2 (H2O)2Cl6] (L = 1,2-Me2Im or 4-MeIm), [Ru(2-Me-1-VIm)3Cl3] · H2O and [Ru(2-EtIm)3(H2O)Cl2]. These compounds were characterised by elemental analyses, conductometric measurements, i.r. and electronic spectral analyses. Magnetic moments range from 1.01 to 1.9 B.M. The e.s.r. spectra and g values of some of the compounds are indicative of high distortion.  相似文献   

4.

Reactions of 2-hydroxyimino-1-methylpropylidene (acetyl-) and (benzoylhydrazine) with copper(II) chloride, nitrate and acetate were studied. Three types of copper(II) complexes of general formula [Cu(H2L)Cl2], [{Cu(HL)}2][sdot]2NO3[sdot]nH2O and [{Cu(L)}2], where H2L, HL, and L refer, respectively, to the neutral, monoanionic and dianionic ONN tridentate acylhydrazoneoxime ligands, were isolated and characterized. Variable-temperature magnetic susceptibility measurements for [Cu(H2L)Cl2] suggest Curie-Weiss behavior. Both [{Cu(HL)}2][sdot]2NO3[sdot]nH2O and [{Cu(L)}2] show strong antiferromagnetic exchange coupling with ? 2J values of 898-934 and 718-757 cm?1, respectively, indication dimeric structures with oximate bridges.  相似文献   

5.
Two new dioxomolybdenum(VI) complexes, [MoO2L1(CH3OH)] (1) and [MoO2L2(H2O)] (2), where L1 and L2 are dianionic form of N′-(2-hydroxy-3-methoxybenzylidene)-4methoxybenzohydrazide and N′-(2-hydroxy-3methoxybenzylidene)-2-hydroxybenzohydrazide, respectively, have been synthesized and structurally characterized by spectroscopic methods and single-crystal X-ray determination. The complexes are mononuclear molybdenum(VI) compounds. Mo in each complex is octahedral. The difference in the substituent groups in the benzohydrazides leads to coordination of different solvent molecules. Crystals of the complexes are stabilized by hydrogen bonds. The complexes are effective catalysts for sulfoxidation.  相似文献   

6.
Complexes of Co(II), Ni(II), Cu(II), Cd(II), Zn(II) and U(IV)O2 with (Z)-2-oxo-2-(2-(2-oxoindolin-3-ylidene)hydrazinyl)-N-phenylacetamide (H2OI) are reported and have been characterized by various spectroscopic techniques like (IR, UV–Vis, ESR 1H and 13C NMR) as well as magnetic and thermal (TG and DTA) measurements. It is found that the ligand behaves as a neutral tridentate, neutral tetradentate, monoanionic tridentate, monoanionic tridentate and dianionic tridentate. An octahedral geometry for all complexes except [Cu2(H2OI)(OAc)4](H2O)2 and [Cu(HOI)Cl](H2O)2 which have a square planar geometry. Furthermore, kinetic parameters were determined for each thermal degradation stage of some studied complexes using Coats–Redfern and Horowitz–Metzger methods. The bond lengths, bond angles, HOMO, LUMO and dipole moments have been calculated to confirm the geometry of the ligand and the investigated complexes.  相似文献   

7.
Abstract

A series of manganese(III) porphyrins with 4-methylimidazole have been prepared. These are high-spin complexes having general formula [MnIII(THMPP)X(4-MeIm)], where THMP?=?5,10,15,20-tetra(4-hydroxy-3-methoxyphenyl)porphine ligand, X?=?Cl?, Br?, NCS?, or N3? and 4-MeIm?=?4-methylimidazole. All the complexes have been characterized by UV-visible, FT-IR, ESI-MS spectra, elemental analyses and magnetic susceptibility measurements. These manganese(III) porphyrins oxidize aromatic alcohols to aldehydes. The oxidation reactions have been carried out at room temperature in the presence of oxidants such as NaIO4, H2O2, and NaOCl. The comparative studies proved that NaIO4 behaves as the most efficient oxidant in these oxidative transformation reactions.  相似文献   

8.
Summary Mixed ligand diglycinatocopper(II) complexes of the Cu(glygly)L·nH2O type, where glygly stands for [NH2-CH2 CONCH2CO2]2– and L for imidazole (n = 1.5), N-methylimidazole (n = 1), 2-methylimidazole (n = 2), 4-methylimidazole (n = 2), 4-phenylimidazole (n = 2), N-acetylhistamine (n = 2) and NH3 (n = 2), were prepared and characterized by elemental analyses, i.r., vis. and e.p.r. spectroscopic measurements. The molecular structure of [Cu(glygly)(achmH)]·2H2O (achmH = acetylhistamine) was determined using three dimensional XRD data. The structure consists of distorted square planar [Cu(glygly)-(achmH)] units interconnected via the peptide oxygen at the apex to complete a square pyramidal structure, Cu—O-(peptide) 2.477(2) Å. The H2O molecules, not binding directly to the copper ion, involve in intermolecular hydrogen bonding with the copper units. The dianionic glygly ligand and the imidazole ring bind strongly to the central copper ion with Cu—N(amino) 2.045(6) Å, Cu—N-(peptide) 1.891(5) Å, Cu—O(carboxylate) 2.001(4) Å and Cu—N(imidazole) 1.956(5) Å. The dihedral angle between the imidazole nucleus and the CuN3O xy plane is 6.0°. Similar structures with a CuN3O coordination plane are proposed for the imidazole complexes, based on spectroscopic data. The bonding properties of the glygly ligand and the unidentate imidazole ligands are elucidated and discussed with reference to the electronic structures of the complexes deduced from Gaussian analyses.  相似文献   

9.
The [M(1-MeIm)2(H2O)4](Tpht) · 4H2O complexes (where M = Ni, Co; 1-MeIm is 1-methylimidazole; H2Tpht is terephthalic acid) are synthesized and characterized by X-ray diffraction analysis. The ionic structure is built of the [M(1-MeIm)2(H2O)4]2+ cations and (Tpht)2? anions. The metal ions have a distorted octahedral coordination. The cations and anions are united by hydrogen bonding system.  相似文献   

10.
Four dioxomolybdenum(VI) complexes were synthesized by reaction of [MoO2(acac)2] with thiosemicarbazones derived from 5-allyl-2-hydroxy-3-methoxybenzaldehyde (1), 2-hydroxynaphthaldehyde (2), 2,3-dihydroxybenzaldehyde (3), or 5-tert-butyl-2-hydroxybenzaldehyde (4). The ligands were coordinated to molybdenum as tridentate ONS donors. X-ray crystallography showed that the distorted octahedral coordination of molybdenum is completed by methanol (D) in 1a, 3a, and 4a or H2O in 2a. The molecular structures of 1, 3, and 4, and the complexes were determined by single-crystal X-ray crystallography. Binding of the ligand and complexes with calf thymus DNA were investigated by UV, fluorescence titrations, and viscosity measurements. Gel electrophoresis revealed that all the complexes can cleave pBR322 plasmid DNA. The cytotoxic properties of the complexes against human colorectal (HCT 116) cell line showed strong antiproliferative activities in relative order 4a?>?3a?>?1a?>?2a with IC50 values of 1.6, 4.0, 4.8, and 6.7?μM, respectively. The complexes exhibited more activity than the standard reference drug, 5-fluorouracil (IC50 7.3?μM). These studies show that dioxomolybdenum(VI) complexes have potential use in chemotherapy.  相似文献   

11.
In this study, the syntheses of two new Mo(VI) and Ni(II) complexes with H2L tridentate (ONO) Schiff-base ligand have been described and fully characterized by means of elemental analysis, FT–IR, electronic, 1H-NMR spectroscopy and single-crystal X-ray diffraction. In both complexes, the Schiff-base completely deprotonates and coordinates to the metal ion as a dianionic tridentate ligand via the donor oxygens and nitrogen atoms. The coordination numbers of Mo(VI) and Ni(II) are six and four, respectively. The DFT-B3LYP/6–31 + G (d,p) and PBEPBE/6–31 + G (d,p) calculations are carried out for the determination of the optimized structures. Frequency calculations and NBO analysis are also performed for characterization. According to the theoretical analysis of the complexes, ligand-to-metal donation is greater than back donation. NBO data revealed that the main contribution of the frontier orbitals belongs to L−2.  相似文献   

12.
(NH3CH2CH2NH2)3[Mo(Ⅴ)O2(O2C6H4)2] (1), (NH3CH2CH2NH2)2.5[Mo(Ⅴ)o.sW(Ⅵ)o.502(O2C6H4)2] (2) and(NH3CH2CH2NH2)2[VC(Ⅵ)O2(O2C6H4)2] (3) were synthesized, structurally characterized by X-ray diffraction analysis, and studied on their interactions with ATP, their DNA cleavage activities and antitumor properties. The redox state of molybdenum was not changed on going from crystal to aqueous solutions in complexes 1 and 2, while tungsten underwent reduction from W(VI) to W(V) in complexes 2 and 3. ATP promoted the oxidation of both molybdenum and tungsten from M(Ⅴ) to M(Ⅵ) and the hydrolysis of catecholate ligands in solution consisting of ATP and the complexes. Complex 1 possesses fairly good activity to DNA cleavage and against tumor S180 in mice, and is more effective than the control drug cyclophosphamide under the identical conditions. However, complexes 2 and 3 exhibited marginal effectiveness. The effectiveness of anti-tumor of the complexes was related positively to their DNA cleavage activities and their hydrolysis of catecholate ligands.  相似文献   

13.
Co(II), Ni(II) and Cu(II) nitrate complexes with btmpp, namely ([Co(btmpp)(H2O)2(NO3)]NO3 (1), [Ni(btmpp)(H2O)(NO3)]NO3 (2) and [Cu(btmpp)(MeOH)(NO3)]NO3 (3), where btmpp = 2,6-bis(3,4,5-trimethyl-N-pyrazolyl)pyridine), have been synthesized and characterized by physicochemical and spectroscopic methods. The crystal structure of complex 1 has been determined by single crystal diffraction at 100K. In all the complexes, btmpp is coordinated in a tridentate mode through its nitrogen atoms. One of the nitrates in complex 1 is terminally bonded to the metal center through the oxygen atom, whereas the other one is out of the coordination sphere. The Co(II) atom in complex 1 is hexa-coordinated with a CoN3O3 distorted octahedral environment. Decomposition of three complexes was analyzed thermogravimetrically. All three complexes decompose similar to explosive material.  相似文献   

14.
Four new nickel(II) phthalate compounds: mononuclear complexes [Ni(Im)]6(Pht)·H2O (1), [Ni(Pht)(Im)3(H2O)2]·H2O (2) and [Ni(Pht)(2-MeIm)3(H2O)3]·H2O (3), and coordination polymer [Ni(Pht)(4-MeIm)2(H2O)]n (4) (where Pht = dianion of o-phthalic acid, Im = imidazole, 2-MeIm = 2-methylimidazole, 4-MeIm = 4-methylimidazole) have been synthesized. The complexes 14 were characterised by elemental analysis, IR data, thermogravimetric, and X-ray diffraction analyses. X-ray analysis shows that the asymmetric unit of 1 consists of [Ni(Im)]62+ cation, Pht2− anion and solvate H2O molecule. The phthalate dianion does not take part in coordination to metal ion. The cations, anions and water molecules are linked via   N–H??O and O–H??O interactions forming 2D hydrogen-bonded networks. The structures of 2 and 3 are similar to other mononuclear Ni(II) phthalate complexes where Pht2− anions act as monodentate ligands and uncoordinated carboxylate oxygen atoms participate in the formation of hydrogen bonded double-chains. The structure of 4 consists of [Ni(4-MeIm)2(H2O)] building units connected by phthalate ions to form helical chains. The complexes 14 were tested for their ability to increase the biosynthesis of enzymes.  相似文献   

15.
New heteronuclear complexes containing oxorhenium(V), Cu(II), Ni(II), Fe(III), UO2(VI) and Th(IV) ions were prepared by the reaction of the complex ligand, [ReO(H4L)Cl]Cl2, where H4L = 8,17-dimethyl-6,15-dioxo-5,7,14,16-tetrahydrodibenzo[a,h][14]annulene-2,11-dicarboxylic acid, with the previous transition and actinide salts. Three heteronuclear Cu(II) complexes were isolated depending on the ratio of [ReO(H4L)Cl]Cl2?:?Cu(II) ion. When the ratios were 1?:?0.5, 1?:?1 and 1?:?2, the heteronuclear complexes {[ReO(H3L)Cl]2CuCl2(OH2)2}SO4 · H2O (I), [ReO(H3L)Cl2Cu(OH2)2(SO4)] (II) and {ReO(H2L)Cl[Cu(OH2)3 SO4]2} (III) were obtained, respectively. Heteronuclear complexes of the other metal cations were obtained by mixing [ReO(H4L)Cl]Cl2 with the metal salt in the ratio 1?:?1 to obtain the heteronuclear complexes [ReO(H3L)Cl2Ni(OH2)2](NO3)2 (IV), [ReO(H3L)Cl3Fe(OH2)3](NO3)2 (V), [ReO(H3L)ClUO2(NO3)2 (OH2)]Cl (VI) and [ReO(H3L)Cl3Th(NO3)2(OH2)]NO3 · 2H2O (VII). The complex ligand coordinates with the heterometal ion via the carboxylate group, and the infrared bands νas COO and νs COO indicate that the carboxylate acts as a unidentate ligand to the heterometal cations. Cu(II) and Fe(III) cations in the heteronuclear complexes have octahedral geometry, while Ni(II) is square planar. Thermal studies explored the possibility of obtaining new heteronuclear complexes pyrolytically in the solid state from the corresponding mother complexes. The structures of the complexes were elucidated by conductance, IR and electronic spectra, magnetic moments, 1H NMR and TG-DSC measurements as well as by mass spectroscopy.  相似文献   

16.
Reactions of 2-(L-carboxyl-2-hydroxyphenyl)thiazolidine with different chromium(III) salts [CrCl3?·?6H2O, K3[Cr(SCN)6], NH4[Cr(NH3)2(SCN)4]?·?H2O, [Cr(urea)6]Cl3?·?3H2O and [Cr(CH3COO)2H2O]2] under varied reaction conditions afforded many new mixed-ligand chromium(III) complexes. The ligand is a tridentate dibasic NSO donor except for complexes 1 and 4 where two moles of the ligand are present for each molecule of complex, one functioning as a dibasic tridentate (NSO) and the other as a monobasic bidentate (NS) (phenolic OH and carboxylic COOH groups remaining uncoordinated). The complexes have been characterized by elemental analyses, magnetic susceptibilities, molar conductances, molecular weights and spectroscopic (IR, Uv-vis) data. The ligand field parameters and NSH Hamiltonian parameters suggest tetragonal geometries of the complexes.  相似文献   

17.
Eight new molybdenum(VI) complexes with 4-(diethylamino)salicylaldehyde and 2-hydroxy-3-methoxybenzaldehyde thiosemicarbazones have been prepared. They were characterized as mononuclear [MoO2LD] or dinuclear [{MoO2L}2D] complexes. In all the compounds the MoO22+ core is coordinated by a tridentate ONS thiosemicarbazonato ligand and by the N-donor molecule (imidazole, pyridine or γ-picoline). All the complexes were characterized by chemical analysis, IR spectroscopy and thermogravimetry. Three of the mononuclear complexes, dioxo[(2-hydroxy-3-methoxybenzaldehyde thiosemicarbazonato)(pyridine)]molybdenum(VI), dioxo[(2-hydroxy-3-methoxybenzaldehyde thiosemicarbazonato)(γ-picoline)]molybdenum(VI) and dioxo[(2-hydroxy-3-methoxybenzaldehyde thiosemicarbazonato)(imidazole)]molybdenum(VI) were also characterized by single-crystal X-ray structural analysis. A spectrophotometric method for the determination of molybdenum based on extraction of ion-pairs formed by the cationic surfactant and the [MoO(SCN)4] anion is described.  相似文献   

18.
The stability constants and structure of the complexes of CdII and ZnII with 1-ethoxymethylimidazole (ExMeIm), 1-propoxymethylimidazole (PxMeIm), 1-ethoxymethyl-2-methylimidazole (ExMe-2-MeIm) and 1-propoxymethyl-2-methylimidazole (PxMe-2-MeIm) in aqueous solution have been determined by potentiometric methods. ZnII form both tetrahedral and octahedral species with the cited ligands according to the configurational equilibrium type: octahedron tetrahedron, but CdII prefers octahedral coordination of alkoxymethylimidazole complexes in aqueous solution. Retention of the six-coordination form of CdII has also been confirmed by the data obtained for two novel compounds which have been synthesized in the solid state. The crystal and molecular structure of [Cd(ExMeIm)4(NO3)2] (1) has been determined by X-ray diffraction. The coordination geometry around the CdII ion can be considered as slightly distorted tetragonal bipyramidal (CdN4O2). Additionally, another six-coordinate CdII compound with ethoxymethyl-2-methylimidazole [Cd(ExMe-2-MeIm)4(H2O)](NO3)2 (2) has been characterized by spectroscopic (i.r., far i.r., Raman) ES–MS and t.g.a. methods.  相似文献   

19.
Summary Dioxomolybdenum(VI) complexes [MoO2L]H2O and oxomolybdenum(V) complexes [Mo2O3L2]H2O and [Mo2O3(LH)2(OH)2(H2O)2] (where LH2=thiocarbohydrazones derived from thiocarbohydrazide with salicylaldehyde, 5-methyl-, 5-chloro-, 5-bromo-, 3-methoxysalicylaldehyde and 2-hydroxy-1-naphthaldehyde) have been prepared and characterised by elemental analysis, conductivity, magnetic moment, i.r., u.v-vis, e.p.r. and thermal studies. The data suggests that molybdenum(VI) complexes are non electrolytes, diamagnetic, monomeric and have distorted octahedral geometry, whereas the molybdenum(V) complexes are non electrolytes, paramagnetic and have distorted octahedral structures with possible metal intereaction via oxo bridging.  相似文献   

20.
Two copper(II) complexes with the general formula [Cu(L)(H2O)](ClO4)2 (1) and [Cu(L)2](ClO4)2 (2), where L=3-((pyridin-2-ylmethyl)amino)propanamide, were synthesized and characterized by elemental analyses, IR, UV–vis spectroscopy techniques and molar conductance measurements. The crystal structures of the complexes were identified by single crystal X-ray diffraction analysis. The tridentate ligand L acts as an N2O-donor through the nitrogen atoms of the pyridine and amine moieties as well the oxygen atom of the amide group. The copper(II) ions in both complexes have distorted octahedron structures so that the Cu(II) ion in 1 is coordinated by an aqua ligand and a tridentate ligand defining the basal plane, and by two oxygen atoms of the perchlorate ions occupying the axial positions. However, two ligands L are coordinated to the copper(II) ion in 2, where four nitrogen atoms of pyridine and amine groups occupy the equatorial positions and two oxygen atoms of the amide moieties exist in the apices. The chromotropism (halo-, solvato- and ionochromism) of both complexes were studied using visible absorption spectroscopy. The complexes are soluble in water and organic solvents and display reversible halochromism. The solvatochromism property is due to structural change followed by solvation of the vacant sites of the complexes. The complexes demonstrated obvious ionochromism and are highly sensitive and selective towards CN? and N3? anions in the presence of other halide and pseudo-halide ions.  相似文献   

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