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1.
Two new series of copper(II), nickel(II), cobalt(II), zinc(II), iron(III), chromium(III), vanadyl(IV) and uranyl(VI) complexes with two bifunctional tridentate Schiff base, H4L1 and H2L2 ligands have been prepared. The Schiff base, H4L1 and H2L2, ligands were synthesized by the condensation of 4,6-diacetylresorcinol with o-aminophenol or o-phenylenediamine. The ligands are either di- or tetra-basic with two symmetrical sets of either OON or NNO tridentate chelating sites. The ligands and their metal complexes have been characterized by elemental analysis, 1H-n.m.r., FT-IR, mass, electronic, esr spectra and thermal gravimetric analysis and magnetic susceptibility. With the exception of CoII ion with H2L2 which afforded a trinuclear complex, a variety of binuclear complexes for the rest of the metal complexes were obtained with the ligands in its di- or tetra-deprotonated forms. The bonding sites are the azomethine and amino nitrogen atoms, and phenolic oxygen atoms. The metal complexes exhibit different geometrical arrangements such as square planar, tetrahedral, square pyramid and octahedral arrangement.  相似文献   

2.
The reaction of a series of tripodal ligands, H3L1,2 and L3-6, with [M(PPh3)2Cl2] (M = Ru, Os) affords a family of coordination cage compounds of the type [MIIIL1,2] (1-4) or [MIIL3-6](BPh4)2 (5-12). The Schiff base ligands (H3L1, L3, L5) have been synthesized by condensation of tris(2-aminoethyl)amine with salicylaldehyde, pyridine-2-aldehyde and 1-methyl-2-imidazolecarboxaldehyde. These ligands were further reduced and subsequently methylated to form the new ligands (H3L2, L4, L6). Single crystal X-ray diffraction studies of 1 and 2 show that the tripodal ligand wraps around the metal center as a hexadentate ligand to form a cage. All the synthesized compounds have been thoroughly characterized by ESI-MS, FT-IR, UV-Vis and NMR spectroscopic methods. To the best of our knowledge, this is the first ever report of osmium complexes with tris(2-aminoethyl)amine based tripodal ligands. DFT calculations were performed to obtain geometry optimized structures of all the other complexes (3-12).  相似文献   

3.
Three novel Schiff base Cd(II) trimeric complexes, [Cd3(L1)2(SCN)2(CF3COO)2] (1), [Cd3(L1)2(SCN)2(HCONMe2)] (2) and [Cd3(L2)2{N(CN)2}2] (3) have been prepared from two different symmetrical Schiff bases H2L1 and H2L2 (where H2L1 = N1,N3-bis(salicylideneimino)diethylenetriamine, a potentially pentadentate Schiff base with a N3O2 donor set, and H2L2 = N1,N3-bis(3-methoxysalicylideneimino)diethylenetriamine, a potentially heptadentate Schiff base with a N3O4 donor set). All the complexes have been synthesised under similar synthetic procedures and their crystal structures have been established by single crystal X-ray diffraction methods. The ligands and their metal complexes have been characterised by analytical and spectroscopic techniques. Among the three complexes, 1 and 3 are linear whereas 2 is a cyclic trimer. In 1 and 3, all the doubly phenoxo bridged Cd(II) metal centres are in a distorted octahedral environment. In complex 2, two of the three Cd(II) centres reside in a distorted octahedral environment and the remaining one enjoys a monocapped octahedral geometry. Altogether the variety in the bridging mode of two new salen-type ligands has been established through these complexes.  相似文献   

4.
Summary 2,3-Bis(hydroxyimino)-1,2,3,4-tetrahydro-pyrido[2,3-b]pyrazine (H2L), prepared from 2,3-diaminopyridine and cyanogen-di-N-oxide has been converted into nickel(II), palladium(II), copper(II), cobalt(II), and cobalt(III) complexes (H2L) with a 12 metal:ligand ratio. The ligands coordinate through the two N atoms, as do most vicinal dioximes. [(LH)Cl(H2O)Cd], contains a six-membered chelate ring. [Co(HL)2(L)Cl] has also been prepared using triphenylphosphine, triphenylarsine, thiophene and chloride as axial ligands. The structure of thevic-dioxime and its complexes are proposed on the basis of elemental analysis, i.r.,1H-n.m.r. and uv-visible measurements.  相似文献   

5.
Summary New potential tetradentate ligands, N-benzoyl-N-thiobenzohydrazide (H2BTBH) and N-salicyl-N-thiobenzohydrazide (H2SBTH) have been prepared and characterized. Their complexes with CoII, NiII and ZnII have been prepared and characterized on the basis of elemental analyses, magnetic susceptibility measurements, and u.v.-vis., i.r. and 1H-n.m.r. spectral studies. The bonding and stereochemistries of the complexes are discussed. H2BTBH, H2SBTH and the complexes have been screened towards a number of bacteria.  相似文献   

6.
New series of manganese(III) complexes and amino acid Schiff bases have been prepared from 2-hydroxy-1-naphthaldehyde and α-amino acids [L-aspartic acid (Asp), L-asparagine (Asn), L-glutamic acid (Glu) and L-glutamine (Gln)]. The structures of the ligands and manganese complexes were identified using elemental analyses, i.r, electronic spectra, 1H-n.m.r spectra, magnetic moment measurements and thermogravimetric analyses (t.g.a). The results suggest that H2L1: [N-(2-hydroxy-1-naphthylidene) aspartic acid] and H2L3: [N-(2-hydroxy-1-naphthylidene)glutamic acid] Schiff bases behave as trianionic tetradentate species and coordinate to Mn(III) ion according to the general formula [MnL] · xH2O complexes. But, H2L2: [N-(2-hydroxy-1-naphthylidene) asparagine] and H2L4: [N-(2-hydroxy-1-naphthylidene)glutamine] Schiff bases behave as dianionic tridentate and coordinate to Mn(III) ion in the general formula for [MnL(OOCH3)] · xH2O complexes.  相似文献   

7.
In the present study two new series of Copper(II), Nickel(II) and Cobalt(II) complexes with two newly synthesized Schiff base ligands 4,6-bis(1-(4-bromophenylimino)ethyl)benzene-1,3-diol (H2L1), 4,6-bis(1-(4-methoxyphenylimino) ethyl)benzene-1,3-diol (H2L2) and organic ligands 8-hydroxy quinoline, 1,10-phenanthroline have been prepared. The Schiff bases H2L1 and H2L2 ligands were synthesized by the condensation of 4,6-diacetyl resorcinol with 4-bromo aniline and 4-methoxy aniline. The ligands and their metal complexes have been characterized by FT-IR, Mass, 1H NMR, UV–Vis., elemental analysis, ESR and Thermal gravimetric analysis. The Schiff base and their metal complexes were tested for antimicrobial activity against gram positive bacteria Staphylococcus aureus, Streptococcus pyogenes and gram negative bacteria Escherichia coli, Pseudomonas aeruginosa and fungus Candida albicans, Aspergillus niger and Aspergillus clavatus using Broth Dilution Method.  相似文献   

8.
Mono- and binuclear VO(IV), Ce(III), Th(IV) and UO2(VI) complexes of thiosemicarbazone, semicarbazone and thiocarbohydrazone ligands derived from 4,6-diacetylresorcinol were synthesized. The structures of these complexes were elucidated by elemental analyses, IR, UV–vis, ESR, 1H NMR and mass spectra as well as conductivity and magnetic susceptibility measurements and thermal analyses. The thiosemicarbazone (H4L1) and the semicarbazone (H4L2) ligands behave as dibasic pentadentate ligands in case of VO(IV) and UO2(VI) complexes, tribasic pentadentate in case of Ce(III) complexes and monobasic pentadentate in case of Th(IV) complexes. However, the thiocarbohydrazone ligand (H3L3) acts as a monobasic tridentate ligand in all complexes except the VO(IV) complex in which it acts as a dibasic tridentate ligand. The antibacterial and antifungal activities were also tested against Rhizobium bacteria and Fusarium-Oxysporium fungus. The metal complexes of H4L1 ligand showed a higher antibacterial effect than the free ligand while the other ligands (H4L2 and H3L3) showed a higher effect than their metal complexes. The antifungal effect of all metal complexes is lower than the free ligands.  相似文献   

9.
We have synthesized the three Schiff-base ligands H2L1–H2L3 and their CoII, FeIII and RuIII metal complexes. All compounds have been characterized by analytical and spectroscopic methods. Oxidation of cyclohexane has been done by the metal complexes in CH3CN using H2O2 and/or t-butylhydroperoxide (TBHP) as a co-catalyst. The keto-enol tautomeric forms of the ligands have been studied in polar and non-polar organic solvents. Electrochemical properties of the complexes have been studied at different scan rates. Thermal studies were carried out for the compounds. The ligands H2L1–H2L3 were mutagenic on Salmonella Typhimurium TA 98 strain in the presence and/or absence of S9 mix. While the ligands H2L1 and H2L2 showed mutagenic activity on the strain TA 100 with and without S9 mix, the ligand H2L3 was not mutagenic for TA 100. Antimicrobial activity studies of the compounds have also been carried out.  相似文献   

10.
Complexes of CoII with N,N-bis-(3-carboxy-1-oxopropanyl)-1,2-ethylenediamine(L1), N,N-bis-(3-carboxy-1-oxopropanyl)-1,2-phenylenediamine(L2), N,N-bis-(2-carboxy-1-oxophenelenyl)-1,2-phenylenediamine(L3) and N,N-bis-(3-carboxy-1-oxoprop-2-enyl)-1,2-phenylenediamine(L4) have been prepared and characterized by elemental analysis, vibrational spectra, magnetic susceptibility measurements, electronic spectra and thermal studies. Stability constants of the complexes have been evaluated potentiometrically. Vibrational spectra indicate coordination of amide and carboxylate oxygens of the ligands along with two water molecules giving a MO6 weak field octahedral chromophore. Electronic spectra support octahedral geometry around CoII. The [Co(L1)-(H2O)2] · 2H2O complex has the maximum activation energy and [Co(L3)(H2O)2] complex has the minimum activation energy. The order of stability constants of the CoII complexes with various ligands is due to their -donor abilities.  相似文献   

11.
Four different types of new ligands Ar[COC(NOH)R] n (Ar=biphenyl, n = 1 H2L1; Ar=biphenyl, n = 2 H4L2; Ar=diphenylmethane, n = 1 H2L3; Ar=diphenylmethane, n = 2 H4L4; R=2-amino-4-chlorophenol in all ligands) have been obtained from 1 equivalent of chloroketooximes Ar[COC(NOH)Cl] n (HL1-H2L4) and 1 equivalent of 2-amino-4-chlorophenol (for H2L1 and H2L3) or 2 equivalent of 2-amino-4-chlorophenol (for H4L2 and H4L4). (Mononuclear or binuclear cobalt(II), nickel(II), copper(II) and zinc(II) complexes were synthesized with these ligands.) These compounds have been characterized by elemental analyses, AAS, infra-red spectra and magnetic susceptibility measurements. The ligands have been further characterized by 1H NMR. The results suggest that the dinuclear complexes of H2L1 and H2L3 have a metal:ligand ratio of 1:2; the mononuclear complexes of H4L2 and H4L4 have a metal:ligand ratio of 1:1 and dinuclear complexes H4L2 and H4L4 have a metal:ligand ratio of 2:1. The binding properties of the ligands towards selected transition metal ions (MnII, CoII, NiII, CuII, ZnII, PbII, CdII, HgII) have been established by extraction experiments. The ligands show strong binding ability towards mercury(II) ion. In addition, the thermal decomposition of some complexes is studied in nitrogen atmosphere.  相似文献   

12.
Chiral and racemic Salen-type Schiff-base ligands (H2L1, H2L2 and H2L3), condensed between D-(+)- and D,L-camphoric diamine (also known as (1R,3S)-1,2,2-trimethylcyclopentane-1,3-diamine) and 2-hydroxybenzaldehyde or 3,5-dibromo-2-hydroxybenzaldehyde with a 1:2 molar ratio, have been synthesized and characterized. A series of new nickel(II), palladium(II) and copper(II) complexes of these chiral and racemic ligands exhibiting different coordination number (4, 5 and 6) have been characterized with the formulae [NiL1]·CH3OH (3), [NiL1]·H2O (4), [NiL2] (5), [PdL2] (6), [Cu2(L2)2(H2O)] (7) and [NiL3(DMF)(H2O)] (8). Different solvent molecules in 3 and 4 (methanol and water molecules) as well as different apical ligands in 7 and 8 (water and DMF molecules) are involved in different O–H···O hydrogen bonding interactions to further stabilize the structures. UV–Vis (UV–Vis), circular dichroism (CD) spectra and thermogravimetric (TG) analyses for the metal complexes have also been carried out.  相似文献   

13.
Two new Schiff base ligands containing 2,4–disubstituted thiazoles and cyclobutane rings, 4-(1-methyl-1-phenylcyclobutane-3-yl)-2-(2-hydroxy-3-methoxybenzylidenehydrazino)thiazole (L1H), 4-(1-methyl-1-p-xylylcyclobutane-3-yl)-2-(2-hydroxy-3-methoxybenzylidenehydrazino)thiazole (L2H) and their mononuclear complexes with a 1:2 metal–ligand ratio have been prepared from acetate salts of CoII, CuII, NiII and ZnII in EtOH. The authenticity of the ligands and their complexes have been established by microanalyses, i.r., 13C- and 1H-n.m.r. spectra, and by magnetic susceptibility and conductivity measurements. The complexes are mononuclear. Thermal properties of the ligands and complexes have been studied by t.g.a. and d.s.c. techniques. Antimicrobial activities of the ligands and their complexes have been tested against six different microorganisms; three are yeast and three are bacteria. One of the ligands and many of the complexes were found to be active against some of the microorganisms studied.  相似文献   

14.
Two new macrocyclic ligands 1,4,7,9,12-pentaaza-10,11-dioxo-8,9,12,13-bis-(1-oxo-3-thio-2-hydropyrimidine)-trideca-7,13-diene, (L1) and 1,4,7,9,12-pentaaza-10,12-dioxo-8,9,13,14-bis-(1-oxo-3-thio-2-hydropyrimidine)-tetradeca-7,14-diene, (L2) and their complexes with CrIII, MnII, FeIII, CoII, NiII, CuII and ZnII have been synthesized, and characterized by elemental analysis, i.r., 1H-n.m.r., e.p.r., u.v.–vis. spectroscopy, magnetic susceptibility and conductance measurements. The conductivity measurements suggest that the complexes of divalent metal ions are 1:1 electrolytes whereas the trivalent metal ions are non-electrolytes. On the basis of electronic spectra and magnetic moment measurements the CrIII and FeIII complexes are octahedral, while the divalent metal complexes are tetrahedral except for the NiII and CuII complexes which are proposed to have square planar geometry. All the ligands and their complexes have been screened against gram-positive bacteria Staphylococcus aureus and gram-negative bacteria E. coli. The results show that they inhibit the growth of bacteria.  相似文献   

15.
Two new vic-dioxime ligands, (E,E)-N-{4-[(1,4-dioxaspiro[4.4]non-2-ylmethyl)amino]butyl}-N-hydroxy-2-(hydroxyimino)ethanimidamide (L1H2) and (E,E)-N-{4-[(1,4-dioxaspiro[4.5]dec-2-ylmethyl)amino]butyl}-N-hydroxy-2-(hydroxyimino)ethanimidamide (L2H2) containing two different heteroatoms (N,O) have been prepared from anti-chloroglyoxime, N-(1,4-dioxaspiro[4.4]non-2-ylmethyl)butane-1,4-diamine (3) and N-(1,4-dioxaspiro[4.5]dec-2-ylmethyl)butane-1,4-diamine (4). CoII, NiII and CuII complexes of the ligands have a metal:ligand ratio of 1:2 and the ligands coordinate through the two N atoms, as do most of the vic-dioximes. However, ZnII complexes of the ligands have a metal:ligand ratio of 1:1 and the ligands are coordinated only by the N, O atoms of the vic-dioximes. In the CoII complexes two water molecules, and in the ZnII complexes a chloride ion and a water molecule, are also coordinated to the metal ion. The structures of the compounds were determined by a combination of elemental analysis, magnetic moments, molar conductances, thermogravimetric analysis (t.g.a.) and spectroscopic (u.v.–vis., i.r., 1H- and 13C-n.m.r.) data.  相似文献   

16.
Summary Zr(acac)4 undergoes ligand exchanges with various tri- and tetradentate Schiff base ligands, forming compounds of the Zr(L)2 type (H2L=tetradentate H2Sal2en, H2Sal2pn, H2Sal2 o-phen and the tridentate H2SAP) and Zr(acac)2L (H2L=H2SAN. H2SAE). Upon reaction with a combination of tri- and tetradentate ligands, Zr(acac)4 yields Zr(L)(L) complexes (H2L=H2Sal2en or H2Sal2 o-phen; H2L=H2SAN, H2SAE, or H2SAP), which have been characterised by analytical data, m.ps, electrical conductivities, i.r. and n.m.r (1H and13C) spectra, they have a coordination number of 6, 7 or 8.  相似文献   

17.
Two new N-pyrazole, P-phosphinite hybrid ligands 3-(3,5-dimethyl-1H-pyrazol-1-yl)propyldiphenylphosphinite (L3) and 2-(3,5-diphenyl-1H-pyrazol-1-yl)ethyldiphenylphosphinite (L4) are presented. The reactivity of these ligands and two other ligands reported in the literature (3,5-dimethyl-1H-pyrazol-1-yl)methyldiphenylphosphinite (L1) and 2-(3,5-dimethyl-1H-pyrazol-1-yl)ethyldiphenylphosphinite (L2) towards [RhCl(CO)2]2 (1) have been studied and complexes [RhCl(CO)L] (L = L2 (2), L3 (3) and L4 (4)) have been obtained. For L1 only decomposition products have been achieved. All complexes were fully characterised by analytical and spectroscopic methods and the resolution of the crystalline structure of complexes 2 and 3 by single-crystal X-ray diffraction are also presented. In these complexes, the ligands are coordinated via κ2(N,P) to Rh(I), forming metallocycles of seven (2 and 4) or eight (3) members and finish its coordination with a carbonyl monoxide and a trans-chlorine to phosphorus atom. In both complexes, weak intermolecular interactions are present. NMR studies of complexes 2-4 show the chain N-(CH2)x-O becomes rigid and the protons diastereotopic.  相似文献   

18.
Summary TheN-methyl-N-ethylO-ethylcarbamate ligand (L) has been synthesized and its UCl44·2 L, UO2(NO3)2 · 2 L and ThCl4·3L complexes isolated. In addition, the UCl44-2L complex (where L=N,N-diethylO-ethylcarbamate) is described. From the i.r. spectra, it is clear that the ligands bind to the metal through the carbonyl oxygen atom. The1H n.m.r. spectra of ligands and complexes are reported and discussed.  相似文献   

19.
The cyclopentadienyl ruthenium complexes CpRuL2SCO-het (Cp = η5-C5H5; L2 = 2PPh3 (1), dppe (2)) bearing heterocyclic thiocarboxylate ligands have been synthesized from the reaction of CpRuL2SH with heterocyclic acid chlorides (ClCO-2-C4H3S (a); ClCO-2-C4H3O (b); ClCO-1-C4H8N (c)). Bubbling of CO gas through a THF solution of (1) produced the mixed carbonyl–phosphine complexes CpRu(PPh3)(CO)SCO-het (3) with high yields. Complexes (1)-(3) were characterized by spectroscopic methods (i.r., 1H-n.m.r., 31P-n.m.r.) and elemental analysis. The molecular structure of CpRu(PPh3)2SCO-2-C4H3S (1a) verifies that the thiocarboxylate ligands bind via the sulfur atom (Ru–S = 2.406(2) Å).  相似文献   

20.
Summary The template reaction of isonitrosoacetylacetone (Hina) witho-phenylenediamine (o-phenen) in the presence of (MeCO2)2Ni·4H2O in EtOH yielded three types of nickel(II) complexes (depending on the molar ratio of the reactants) formulated as L1Ni(O2CMe)·2H2O (1), (L1)2Ni (2), and L2Ni·H2O (3). HL1 and H2L2 are the half unit and symmetric Schiff base ligands obtained from the (11) and (21) condensation of (Hina) with (o-phenen) respectively. The (11) molar ratio reaction of (1) with either acetylacetone (Hacac) or (Hina) in CHCl3 led to the formation of mixed ligand complexes L1Ni(acac)·H2O (4) and L1Ni(ina)·H2O (5) whereas a similar reaction with salicylaldehyde (Hsal) produced L3Ni (6); H2L3 is the unsymmetric Schiff base formed by the (11) condensation of the amino group in (1) with (Hsal). Analytical, spectral and magnetic moment evidence are compatible with the suggested structures of the metal complexes.This paper is a summary of the M.Sc. thesis of S. M. Imam.  相似文献   

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