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1.
Two novel heterotrimetallic tetranuclear complexes [Cu(H2L)(CH3OH)]2Gd(DMF)Fe(CN)6·2H2O·DMF (1) and [Cu(H2L)(CH3OH)]2Tb(H2O)0.57(DMF)0.43Fe(CN)6·5.5H2O (2) are reported (H4L = N,N′-ethylenebis(3-hydroxysalicylidene)). The central Ln(III) ion is surrounded by two neutral [Cu(H2L)(CH3OH)] moieties, forming a Cu2Ln trinuclear unit. The [Fe(CN)6]3? anion is weakly coordinated to one Cu(II) ion of [Cu(H2L)(CH3OH)] through a cyanide nitrogen atom with the N–Cu distance of ca. 3.2 Å. Magnetic susceptibility measurements indicate the presence of overall ferromagnetic interactions in complexes 1 and 2. The magnetic coupling constant in complex 1 is J Cu1Gd1 = 4.54 cm?1 and J Cu2Gd1 = 7.97 cm?1 based on \( \hat{H} = - 2J_{\text{Cu1Gd1}} \hat{S}_{\text{Cu1Gd1}} - 2J_{\text{Cu2Gd1}} \hat{S}_{\text{Cu2Gd1}} \) . Dynamic AC magnetic susceptibility studies reveal that complex 2 shows frequency-dependent out-of-phase signals, typical of single molecule magnet behavior. The energy barrier for complex 2 under a 2 kOe applied DC magnetic field is 13 K.  相似文献   

2.
A prolonged storage of a solution of RhCl3·nH2O in N,N-dimethylformamide (DMF) at room temperature is attended by the consecutive formation of two precipitates, which mainly contain the [(CH3)2NH2][RhCl5(DMF)] complex (I) and the complex [RhCl3(DMF)3] (II) liberates. The addition of PPh4Cl to an aqueous solution of complex I brings about the precipitation of [PPh4][RhCl4(H2O)2] (III). Complex II (a mixture of mer-and fac-isomers) can be obtained also by treatment of [RhCl3(CH3CN)3] with DMF. In the course of the latter reaction, the formation of intermediate complex [RhCl3(CH3CN)2(DMF)] (IV) is observed. Complexes I–IV are characterized by elemental analysis; complexes I, II, and IV are characterized by the IR and 1H and 13C NMR spectra. The structures of III and IV are determined by X-ray diffraction analysis.  相似文献   

3.
A redox reaction that occurs in the [Cu2B10H10]/Phen system in CH3CN/DMSO and CH3CN/DMF in air yields a Cu(II) binuclear complex, [(Phen)2Cu(CO3)Cu(Phen)2]2+. The [Cu2(Phen)4(μ-CO3)]B10H10 · 2.5DMSO · 2H2O (I) and [Cu2(Phen)4(μ-CO3)]B10H10 · 4DMF (II) compounds have been isolated and studied by X-ray crystallography at 150 K and EPR at 295 K. Their magnetic properties have been studied in the range 300–2 K. In the cations of both compounds, the bridging CO 3 2? group is bidentately coordinated to two Cu atoms. The cations in I and II have different spatial orientations of the Cu-O bonds: anti-syn and anti-anti, respectively. Compound I has weak magnetic interactions caused by a short Cu…Cu distance (4.441 Å) in the dimer. No exchange coupling is observed in II.  相似文献   

4.
The reactions of SnCl4 with picolinoylhydrazones of 2-hydroxybenz-(2-hydroxynaphth)aldehydes (H2Ps, H2Pnf) in CH3OH gave non-electrolyte complexes [SnCl3(Ps · H)] · CH3OH (I) and [SnCl3(Pnf · H)] · CH3OH (II). The imide form of the ligand coordinated to Sn(IV) through the azomethine nitrogen atom and oxyazine and oxy oxygen atoms was proved by UV/Vis, IR, and 1H NMR spectroscopy. The negative charge on the coordination unit thus arising is counterbalanced by the positive charge caused by the protonation of ligands at the pyridine nitrogen atom of the heterocycle. It was shown that dehydrochlorination of the complexes affords tin-containing species, which correlates with the presence of the corresponding peaks [SnCl2(Ps)]+ and [SnCl2(Pnf)]+ in their mass spectra. The molecular and crystal structures of complexes I and II were determined by X-ray diffraction.  相似文献   

5.
Two new cyano-bridged Cu(II)-Fe(II) binuclear complexes, [Cu(L1)Fe(CN)5(NO)] (I) [L1 = 1,3,6,8,11,14-hexaazatricyclo[12.2.1.18,11]octadecane and [Cu(L2)Fe(CN)5(NO)] · 2H2O (II) L2 = 1,3,6,9,11,14-hexaazatricyclo[12.2.1.16,9]octadecane, have been assembled and structurally characterized by spectroscopy and X-ray crystallography. Complex I crystallizes in the monoclinic crystalline system of space group P21/c, while complex II crystallizes in the monoclinic crystalline system of space group P21/n. These two complexes assume a binuclear structure in which the Fe2+ ion is in an octahedron environment and the Cu2+ ion is in a square-prism geometry environment.  相似文献   

6.
Two new cobalt(III) complexes of the hexadentate ligand [1,4-bis[o-(pyridine-2-carboxamidophenyl)]-1,4-dithiobutane] (H2bpctb) with N4S2 donor set atoms have been synthesized. A reaction of Co(CH3COO)2·4H2O with (H2bpctb) leads to the formation of [CoIII(bpctb)]PF6 (1) having a CoN2(pyridine)N′2(amide)S2(thioether) coordination by symmetric bpctb2? ligand. A similar reaction under slightly different conditions, however, gives [CoIII(L a )(L b )] (2), resulting from a C–S bond cleavage reaction triggered by an acetate ion as a base, having CoN2(pyridine)N′2(amide)S(thioether)S′(thiolate) coordination. These two Co(III) complexes have been characterized by elemental analyses and spectroscopic methods, and the crystal and molecular structures of [CoIII(bpctb)]PF6 (1) in the form of the solvate (1·MeOH·H2O) and of [CoIII(L a )(L b )] (2) have been determined by X-ray crystallography. The Co atoms of both complexes exhibit distorted octahedral geometry. The electrochemical investigation of [Co(bpctb)]PF6·MeOH·H2O (1·MeOH·H2O) and [CoIII(L a )(L b )] (2) by cyclic voltammetry reveals a reversible CoIII–CoII redox process at E 1/2 = ?0.32 V (ΔE p = 80 mV); for 1, and E 1/2 = ?0. 87 V (ΔE p = 70 mV) for 2.  相似文献   

7.
The reactions of [MIII(CN)6]3? (M = Cr or Co) with CuII complexes of a tridentate schiff base [Cu(aemp)Cl] or [Cu(aemp)Ac]2 (Haemp = 2-[(2-amino-ethylimino)-methyl]-phenol) give rise to 1D cyanide-bridged bimetallic coordination polymers [Cu4(aemp)4(H2O)2][Cr(CN)6]Cl (1) and [Cu3(aemp)3(H2O)][Co(CN)6]·2H2O·MeOH (2). In complex 1, the six cyanide ligands of the [Cr(CN)6]3? moiety are involved in bridging, while in complex 2 only five cyanide ligands act as bridges to give a neutral chain. Magnetic studies reveal that complex 1 exhibits intermetallic ferromagnetic coupling, with J = 8.2 cm?1.  相似文献   

8.
The thermal decomposition of [RuCl26-p-cymene)]2 (1) and its biologically active N-alkylphenothiazine compounds of composition L[RuCl36-p-cymene)] where L = CPH+ (2), TFH+·HCl (3), and TRH+ (4) (chlorpromazine hydrochloride, CP·HCl; trifluoperazine dihydrochloride, TF·2HCl; and thioridazine hydrochloride, TR·HCl, respectively) has been studied. The crystal and molecular structure of compound 3 was determined earlier by single crystal X-ray diffraction analysis. The thermal data were collected by simultaneous TG/DSC measurements. For evolved gas detection, the qualitative reaction of chlorides with AgNO3 in an acidic solution was applied. The measurements were carried out in the temperature range to 700 °C in nitrogen atmosphere. Compounds of L[RuCl36-p-cymene)] crystallize with water or water/2-propanole. On the basis of thermal data, the trend in the solvent bonding energies was assessed.  相似文献   

9.
The first MnIII complexes with Schiff bases and tricyanomethanide-anion were synthesized: [Mn(salen)C(CN)3(H2O)] (1), [Mn(5-Brsalen)C(CN)3(H2O)] (2), [Mn(salpn)C(CN)3(H2O)] (3), [Mn(3-MeOsalen)C(CN)3(H2O)] (4), [Mn(5-Brsalen)(MeOH)(H2O)][C(CN)3] (5), and [Mn(3-MeOsalpn)(H2O)2][C(CN)3] (6), where SalenH2 is N,N′-bis(salicylidene)ethylenediamine, 5-BrsalenH2 is N,N′-bis(5-bromosalicylidene)ethylenediamine, SalpnH2 is N,N′-bis-(salicylidene)-1,3-diaminopropane, 3-MeOsalenH2 is N,N′-bis(3-methoxysalicylidene)-ethylenediamine, 3-MeOsalpnH2N,N′-bis(3-methoxysalicylidene)-1,3-diaminopropane. The tricyanomethanide anion in complexes 14 acts as a the terminal ligand, whereas in complexes 5 and 6 tricyanomethanide is not coordinated by MnIII and acts as an out-of-sphere counterion. The structures of complexes 14 are characterized by the formation of dimers due to hydrogen bonds between the water molecules and oxygen atoms of the Schiff bases. The Mn...Mn distances inside the dimers are 4.69–5.41 Å. Complex 6 has a zigzag chain structure consisting of the [Mn(3-MeOsalpn)(H2O)2]+ cations bound by double bridging aqua ligands. The study of the magnetic properties of complexes 1, 3, 4, and 6 showed the existence of antiferromagnetic interactions between the MnIII ions through the system of hydrogen bonds.  相似文献   

10.
Comprehensive comparison between the reaction of N,N'-cyclohexane-1,2-diylidene-bis(4-methoxybenzoylhydrazide) (CHMBH) with HgCl2 and Cu(NO3)2 · 2.5H2O salts have been investigated, including the synthesis, structure and kinetic of complex formation. The reactions of CHMBH with HgCl2 or Cu(NO3)2 · 2.5H2O at the same synthetic conditions have been shown to produce completely different type of complexes: [Hg(CHMBH)Cl2] · CH3CN (I) and [Cu33-OH)(CTMB)3(NO3)2(CH3CN)2] · 5CH3CN · H2O (II) (CTMB = cyclohexotriazole-3-(4-methoxybenzamide)). The prepared compounds were characterized using different techniques (NMR, IR, UV-Vis and mass spectroscopies, microelemental analysis, thermogravimetry as well as X-ray powder differection and X-ray single crystal crystallography for I (CIF file CCDC no. 1503398). X-ray crystallography shows that the isolated product of I is a mononuclear complex which contains the [Hg(CHMBH)]2+ core. While, the isolated product of II was a trinuclear Cu(II) cluster [Cu33-OH)(CTMB)3(NO3)2(CH3CN)2] · 5CH3CN · H2O which contains three differently coordinated copper sites. Kinetic studies on the formation of I have been also investigated and compared with that of II. In case of I, the reaction was so slow and exhibits a first-order dependence on the concentration of metal salt and a first-order dependence on the concentration of CHMBH. While in II, the study shows that the reaction is fast and occurs in three distinct phases.  相似文献   

11.
Two new copper complexes [Cu(Hdpa)2(en)] (1) and [{Cu2(μ-na)4(CH3OH)2}·2CH3OH] (2) (where en is ethylene diamine, Hdpa is 2′-carboxy-[1,10-biphenyl]-2-carboxylate anion and na is 1-naphtalenecarboxylate) have been synthesized and their crystal structures were determined by X-ray crystallography. Complex 1 was prepared from the reaction of Cu(NO3)2·3H2O with ethylene diamine and 2,2′-biphenyldicarboxylic acid in a mixture of water and methanol and complex 2 was prepared from the reaction of CuSO4·5H2O with 1-naphtalenecarboxylic acid in methanol. The two complexes were characterized by IR, UV–vis, luminescence and elemental analysis. Moreover, complex 2 was characterized by EPR spectroscopy and thermogravimetric analysis. Complex 1 is a monomer and complex 2 is a dimer with a paddle-wheel structure; both structures are without precedent in the literature.  相似文献   

12.
Complexes of Cu(II) and Co(II) nitrates with 3-phenyl-5,5-dimethyl-5,6-dihydro-1,2,4-triazolo[3,4-a]isoquinoline (L0) of the composition [CuL 2 0 (NO3)2] (I) and [CoL 2 0 (NO3)2] · CH3CN (II) are synthesized and their crystal structures are determined by X-ray diffraction. The L0 ligand is coordinated to the metal atoms through the N atom in position 2 of triazole fragment. The coordination polyhedron of the Cu(II) atom is a square with two additional axial vertices, while that of the Co(II) atom is a tetrahedron with two additional vertices. The NO 3 ? groups in the structures of I and II perform similar anisobidentate function. Complexes I and II are studied by IR and electronic spectroscopy.  相似文献   

13.
Four new mononuclear triazido-cobalt(III) complexes [Co(L 1/2/4 )(N3)3] and [Co(L 3 )(N3)3]·CH3CN where L 1  = [(2-pyridyl)-2-ethyl]-(2-pyridylmethyl)-N-methylamine, L 2  = [(2-pyridyl)-2-ethyl]-[6-methyl-(2-pyridylmethyl)]-N-methylamine, L 3  = [(2-pyridyl)-2-ethyl]-[3,5-dimethyl-4-methoxy-(2-pyridylmethyl)]-N-methylamine, and L 4  = [(2-pyridyl)-2-ethyl]-[3,4-dimethoxy-(2-pyridylmethyl)]-N-methylamine, respectively, were synthesized and structurally characterized. The four complexes were characterized by elemental microanalyses, IR and UV–VIS spectroscopy and X-ray single crystal crystallography. The complexes display two strong IR bands over the frequency region 2,020–2,050 cm?1 assigned for the asymmetric stretching frequency, νa(N3) of the coordinated azides indicating facial geometry. The molecular structure determinations of the complexes were in complete agreement with fac-[Co(L)(N3)3] conformation in distorted octahedral Co(III) environment.  相似文献   

14.
Four cyanide-bridged heterometallic complexes {[CuPb(L 1 )][Fe III (bpb)(CN) 2 ]} 2 ·(ClO 4 ) 2 ·2H 2 O·2CH 3 CN (1), {[CuPb(L 1 )] 2 [Fe II (CN) 6 ](H 2 O) 2 }·10H 2 O (2), {[Cu 2 (L 2 )][Fe III (bpb)(CN) 2 ] 2 }·2H 2 O·2CH 3 OH (3) and {[Cu 2 (L 2 )] 3 [Fe III (CN) 6 ] 2 (H 2 O) 2 }·10H 2 O (4) have been synthesized by treating K[Fe III (bpb)(CN) 2 ] [bpb 2-=1,2-bis(pyridine-2-carboxamido)benzenate] and K 3 [Fe III (CN)] 6 with dinuclear compartmental macrocyclic Schiff-base complexes [CuPb(L 1 )] (ClO 4 ) 2 or [Cu 2 (L 2 )]·(ClO 4 ) 2 , in which H 2 L 1 was derived from 2,6-diformyl-4-methyl-phenol, ethylenediamine, and diethylenetriamine in the molar ratio of 2:1:1 and H 2 L 2 from 2,6-diformyl-4-methyl-phenol and propylenediamine in the molar ratio of 1:1. Single crystal X-ray diffraction analysis reveals that compound 1 displays a cyclic hexanuclear heterotrimetallic molecular structure with alternating [FeⅢ (bpb)(CN) 2 ]- and [CuPb(L 1 )] 2+ units. Complex 2 is of a neutral dumb-bell-type pentanuclear molecular configuration consisting of one [Fe(CN)6] 4- anion sandwiched in two [CuPu(L 1 )] 2+ cations, and the pentanuclear moieties are further connected by the hydrogen bonding to give a 2D supramolecular framework. Heterobimetallic complex 3 is a tetranuclear molecule composed of a centrosymmetric [Cu 2 (L2)] 2+ segment and two terminal cyanide-containing blocks [FeⅢ (bpb)(CN)2 ]- . Octanuclear compound 4 is built from two [Fe(CN)6]3- anions sandwiched in the three [Cu 2 L 2 ] 2+ cations. Investigation of their magnetic properties reveals the overall antiferromagnetic behavior in the series of complexes except 2.  相似文献   

15.
New Mn(III) complexes with Schiff bases and dicyanamide are synthesized: [Mn(Salpn)N(CN)2] n (two polymorphous modifications, Ia and Ib), {[Mn(5-BrSalen)N(CN)2] · CH3OH} n (II), and [Mn(3-MeOSalen)N(CN)2(H2O)] (III), where SalpnH2 = N,N′-bis(salicylidene)-1,3-diaminopropane, 5-BrSalenH2 = N,N′-bis(5-bromosalicylidene)-1,2-diaminoethane, and 3-MeOSalenH2 = N,N′-bis(3-methoxysalicylidene)-1,2-diaminoethane. Complexes Ia, Ib, and II have the polymer structure in which the dicyanamide anion binds the paramagnetic Mn(III) complexes with the Schiff bases into one-dimensional chains. Unlike them, in complex III the monomer units containing water and the dicyanamide anion as terminal ligands form dimers due to hydrogen bonds. The study of the magnetic properties of complexes Ia and II shows a weak antiferromagnetic interaction between the Mn3+ ions through the dicyanamide bridges in these complexes.  相似文献   

16.
Three new heterometallic coordination compounds, namely, [KCu(I3)(L)2(H2O)2]n(1), [KCu(I3)(L)2(H2O)]n(2) and [CuK4(I3)2(L′)4]n(3), were prepared and characterized(HL=5-methylpyrazine-2-carboxylic acid, HL′=p-tolylacetic acid). Structural studies revealed that 1 and 2 exhibit 3D frameworks with rectangular channels occupied by triiodide ions. Both compounds can be symbolized as a 5-connected net with pcu topology. In compound 3, a one-dimensional polyhedral chain is connected by hexanuclear mask like clusters [Cu2K4O8]. These chains are further linked each other via rare(1,1,3,3)-triiodide ion-bridging units to generate a 3D(4,5,6)-connected net with the point symbol of {12}2{4·122}4{46}{48·62}4{49·66}4. It is noteworthy that water-induced reversible dissolution/reorganization processes occur between 1/2 and [Cu(L)2(H2O)]n·3nH2O. The thermal and photoluminescence properties of compounds 1, 2, and 3 were investigated as well.  相似文献   

17.
Complexes of [Mn(MF)2(Cl)2]·2H2O (1), [Fe(MF)2(Cl)2]Cl·4H2O (2), [Ni(MF·HCl)2(Cl)2]·6H2O (3), [Cu(MF·HCl)2(Cl)2] (4), [Zn(MF·HCl)2](NO3)2·6H2O (5), [Cd2(MF·HCl)(Cl)4(H2O)] (6), [Mg(MF·HCl)2(Cl)2]·6H2O (7), [Sr2(MF·HCl)(Cl)4(H2O)] (8), [Ba(MF·HCl)2(Cl)2]·2H2O (9), [Pt(MF)4] (10), [Au(MF)3]Cl3 (11), and [Pd(MF)2]Cl2 (12) were synthesized from Legitional behavior of metformin drug as a diabetic agent. The authenticity of the transition and non-transition metal complexes were characterized by elemental analyses, molar conductivity, (infrared, UV–Vis) spectra, effective magnetic moment in Bohr magnetons, electron spin resonance, thermal analysis, X-ray powder diffraction as well as scanning electron microscopy. Infrared spectral studies as well as elemental analyses revealed the existence of metformin in the base or hydrochloride salt forms in the chelation state acts as a bidentate ligand while the platinum(IV) complex is coordinated through the deprotonation of –NH group. The magnetic and electronic spectra of Mn(II), Fe(III), Ni(II), and Cu(II) complexes suggest an octahedral geometry. Antimicrobial screening of metformin and its complexes were determined against the (G+ and G?) bacteria (Escherichia coli, Staphylococcus aureus, Bacillus subtilis, and Pseudomonas aeruginosa) and fungi (Aspergillus flavus and Candida albicans).  相似文献   

18.
Two new heterometallic tetranuclear clusters [M2Na2(hmb)4(N3)2(CH3CN)2]·(CH3CN)2 (M = Ni (1), M = Co (2), Hhmb is 2-hydroxy-3-methoxy-benzaldehyde) have been synthesized at room temperature and structurally characterized by elemental analysis, IR spectroscopy, and single crystal X-ray diffraction. Intracluster, compounds 1 and 2 display dominant ferromagnetic interaction through double μ 1,1,1-N3 bridges, while intercluster, 1 and 2 display weak anti-ferromagnetic interaction and ferromagnetic interaction, respectively.  相似文献   

19.
Four Ln(III) coordination polymers, [La2(HBidc)3(H2O)] n (I), [Pr2(HBidc)3(H2O)] n (II), [Sm2(HBidc)3(H2O)] n (III), and [Gd2(HBidc)3(H2O)] n (IV), were synthesized hydrothermally by treating Ln(NO3)3 · 6H2O, NaOH, and H3Bidc (H3Bidc = 1H-benzimidazole-5,6-dicarboxylic acid) at 180°C and characterized by elemental analysis, IR spectra, and single-crystal X-ray structure analyses. Complexes I–IV are isostructural, and each complex contains two crystallographically independent Ln(III), one is seven-coordinated, while the other is eight-coordinated. X-ray crystallography reveals that the complex consists of 3D frameworks with the (34·44·52·66·710·8·9)(3·4·5)(3·4·5) topology. Furthermore, the photoluminescence properties of III has been studied.  相似文献   

20.
Three Ni(II) complexes of cresol-based Schiff-base ligands, namely [Ni2(L1)(NCS)3(H2O)2], (1) [Ni2(L2)(CH3COO)(NCS)2(H2O)] (2) and [Ni2(L3)(NCS)3] (3), (where L1 = 2,6-bis(N-ethylpyrrolidineiminomethyl)-4-methylphenolato, L2 = 2,6-bis(N-ethylpiperidineiminomethyl)-4-methylphenolato and L3 = 2,6-bis{N-ethyl-N-(3-hydroxypropyl iminomethyl)}-4-methylphenolato), have been synthesized and structurally characterized by X-ray single-crystal diffraction in addition to routine physicochemical techniques. Density functional theory calculations have been performed to understand the nature of the electronic spectra of the complexes. Complexes 1?C3 when reacted with 4-nitrophenyl phosphate in 50:50 acetonitrile?Cwater medium promote the cleavage of the O?CP bond to form p-nitrophenol and smoothly convert 3,5-di-tert-butylcatechol (3,5-DTBC) to 3,5-di-tert-butylquinone (3,5-DTBQ) either in MeOH or in MeCN medium. Phosphatase- and catecholase-like activities were monitored by UV?Cvis spectrophotometry and the Michaelis?CMenten equation was applied to rationalize all the kinetic parameters. Upon treatment with urea, complexes 1 and 2 give rise to [Ni2(L1)(NCS)2(NCO)(H2O)2] (1??) and [Ni2(L2)(CH3COO)(NCO)(NCS)(H2O)] (2??) derivatives, respectively, whereas 3 remains unaltered under same reaction conditions.  相似文献   

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