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1.
Some copper(I) complexes of the type [Cu(L)(dppe)]X (1-4) [where L = (3-trifluoromethylphenyl)pyridine-2-ylmethylene-amine; dppe = 1,2-bis(diphenylphosphino)ethane; X = Cl, CN, ClO4 and BF4] have been synthesized by the condensation of 3-aminobenzotrifluoride with 2-pyridinecarboxaldehyde followed by the reaction with CuCl, CuCN, [Cu(MeCN)4]ClO4 and [Cu(MeCN)4]BF4 in presence of dppe. The complexes 1-4 were then characterized on the basis of elemental analysis, IR, UV-Vis and 1H NMR spectral studies. The representative complex of the series 4 has been characterized by single crystal X-ray diffraction which reveal that in complex the central copper(I) ion assumes the irregular pseudo-tetrahedral geometry. The catalytic activity of the complexes was tested and it was found that all the complexes worked as effective catalyst in the amination of aryl halide.  相似文献   

2.
The acid-base properties and Cu(II), Ni(II), Ag(I) and Hg(II) binding abilities of PAMAM dendrimer, L, and of the simple model compounds, the tetraamides of EDTA and PDTA, L1, were studied in solution by pH-metric methods and by 1H NMR and UV-Vis spectroscopy. PAMAM is hexabasic and six pKa values have been determined and assigned. PAMAM forms five identifiable complexes with copper(II), [CuLH4]6+, [CuLH2]4+, [CuLH]3+, [CuL]2+ and [CuLH-1]+ in the pH range 2-11 and three with nickel(II), [NiLH]3+, [NiL]2+ and [NiLH-1]+ in the pH range 7-11. The complex [CuLH4]6+, which contains two tertiary nitrogen and three amide oxygen atoms coordinated to the metal ion, is less stable than the analogous EDTA and PDTA tetraamide complexes [CuL1]2+, which contain two tertiary nitrogen and four amide oxygen atoms, due to ring size and charge effects. With increasing pH, [CuLH4]6+ undergoes deprotonation of two coordinated amide groups to give [CuLH2]4+ with a concomitant change from O-amide to N-amidate coordination. Surprisingly and in contrast to the tetraamide complexes [CuL1]2+, these two deprotonation steps could not be separated. As expected the nickel(II) complexes are less stable than their copper(II) analogues. The tetra-N-methylamides of EDTA, L1(b), and PDTA form mononuclear and binuclear complexes with Hg(II). In the case of L1(b) these have stoichiometries HgL1(b)Cl2, [HgL1(b)H−2Cl2]2−, [Hg2L1(b)Cl2]2+, Hg2L1(b)H−2Cl2 and [Hg2L1(b)H−5Cl2]3−. Based on 1H NMR and pH-metric data the proposed structure for HgL1(b)Cl2, the main tetraamide ligand containing species in the pH range <3-6.5, contains L1(b) coordinated to the metal ion through the two tertiary nitrogens and two amide oxygens while the structure of [HgL1(b)H−2Cl2]2−, the main tetraamide ligand species at pH 7.5-9.0, contains the ligand similarly coordinated but through two amidate nitrogen atoms instead of amide oxygens. The proposed structure of [Hg2L1(b)Cl2]2+, a minor species at pH 3-6.5, also based on 1H NMR and pH-metric data, contains each Hg(II) coordinated to a tertiary amino nitrogen, two amide oxygens and a chloride ligand while that of [Hg2L1(b)H−5Cl2]3−, contains each Hg(II) coordinated to a tertiary amino nitrogen, two amidate nitrogens, a chloride and a hydroxo ligand in the case of one of the Hg(II) ions. The parent EDTA and PDTA amides only form mononuclear complexes. PAMAM also forms dinuclear as well as mononuclear complexes with mercury(II) and silver(I). In the pH range 3-11 six complexes with Hg(II) i.e. [HgLH4Cl2]4+, [HgLH3Cl2]3+, [Hg2LCl2]2+, [Hg2LH−1Cl2]+, [HgLH−1Cl2] and [HgLH−2Cl2]2− were identified and only two with Ag(I), [AgLH3]4+ and [Ag2L]2+. Based on stoichiometries, stability constant comparisons and 1H NMR data, structures are proposed for these species. Hence [HgLH4Cl2]4+ is proposed to have a similar structure to [CuLH4]6+ while [Hg2LCl2]2+has a similar structure to [Hg2L1(b)H−5Cl2]3−.  相似文献   

3.
Reactions of ligands 1-ethyl-5-methyl-3-phenyl-1H-pyrazole (L1) and 5-methyl-1-octyl-3-phenyl-1H-pyrazole (L2) with [PdCl2(CH3CN)2 and K2PtCl4 gave complexes trans-[MCl2(L)2] (L = L1, L2). The new complexes were characterised by elemental analyses, conductivity measurements, infrared, 1H and 13C{1H} NMR spectroscopies and X-ray diffraction. The NMR study of the complex [PdCl2(L1)2], in CDCl3 solution, is consistent with a very slow rotation of ligands around the Pd-N bond, so that two conformational isomers can be observed in solution (syn and anti). Different behaviour is observed for complexes [PdCl2(L2)2] and [PtCl2(L)2] (L = L1, L2), which present an isomer in solution at room temperature (anti). The crystal structure of [PdCl2(L1)2] complex is described, where the Pd(II) presents a square planar geometry with the ligands coordinated in a trans disposition.  相似文献   

4.
The reactions of [Mo(CO)6] towards a 2,6-di(imino)pyridine L1 and related ligands were studied. The reaction with L1 afforded two new complexes, [Mo(CO)4L1] (1) and [Mo(CO)4L2] (2), where L2 is the 2-amino-6-iminopyridine ligand arising from the hydrogenation of one imine function of L1; similar reaction with a 2-acetyl-6-iminopyridine ligand L3 afforded [Mo(CO)4L3] (3). Compounds 1, 2 and 3 have been fully characterised by IR, 1H NMR and X-ray crystallography; they present a metal ion in a pseudo-octahedral environment, the three organic ligands acting with bidentate N2 coordination modes. One of the imine functions in 1, the amine function in 2, and the ketone function in 3 are uncoordinated.  相似文献   

5.
The gas phase molecular structure of a single isolated molecule of [Ag(Etnic)2NO3];1 where Etnic = Ethylnicotinate was calculated using B3LYP method. The H-bonding interaction between 1 with one (complex 2) and two (complex 3) water molecules together with the dimeric formula [Ag(Etnic)2NO3]2;4 and the tetrameric formula [Ag(Etnic)2NO3]4;5 were calculated using the same level of theory to model the effect of intermolecular interactions and molecular packing on the molecular structure of the titled complex. The H-bond dissociation energies of complexes 2 and 3 were calculated to be in the range of 12.220–14.253 and 30.106–31.055 kcal?mol?1, respectively, indicating the formation of relatively strong H-bonds between 1 and water molecules. The calculations predict bidentate nitrate ligand in the case of 1 and 2, leading to distorted tetrahedral geometry around the silver ion with longer Ag–O distances in case of 2 compared to 1, while 3 has a unidentate nitrate ligand leading to a distorted trigonal planar geometry. The packing of two [Ag(Etnic)2NO3] complex units; 4 does not affect the molecular geometry around Ag(I) ion compared to 1. In the case of 5, the two asymmetric units of the formula [Ag(Etnic)2NO3] differ in the bonding mode of the nitrate group, where the geometry around the silver ion is distorted tetrahedral in one unit and trigonal planar in the other. The calculations predicted almost no change in the charge densities at the different atomic sites except at the sites involved in the C–H?O interactions as well as at the coordinated nitrogen of the pyridine ring.
Figure
Molecular structure (left) and electrostatic potentials mapped on the electron density surface (right) calculated by DFT/B3LYP method for Etnic, and complexes 1 and 2  相似文献   

6.
Four new hetero-bimetallic Co3+-Na+ and Co3+-K+ coordination polymers having the molecular formulae [Na(H2O)Co(L)(N3)3]n (1), [Na2Co(L)(N3)3(H2O)5][Co(L)(N3)3] (2), K[Co(L)(NCS)3]·H2O (3) and K[Co(L)2][Co(NCS)4]·0.5H2O (4), were synthesized. Compounds 1-4 were characterized by single crystal X-ray diffraction, IR, UV-Vis, and thermogravimetric methods. These bimetallic systems have EE, EO azide bridge (1, 2) as well as bent (1, 2, 3) and linear (1, 4) aquo bridges. Important features observed among them were: a Z-shaped and diamond-shaped Co2Na2 clusters in 1, a centrosymmetric double ladder like polymer based on Na4 cluster in 2, and a linear KOK core having paddle-wheel structure in 4.  相似文献   

7.
A new easily synthetic route with a 96% yield of ligand 2-(3,5-diphenyl-1H-pyrazol-1-yl)ethanol (L) is obtained. The reactivity of L against Pd(II), Zn(II) and Cu(II) leads to [PdCl2(L)2] (1), [ZnCl2(L)] (2) and [CuCl(L′)]2 (3) (L′ is the ligand L without alcoholic proton), respectively. According to the different geometries imposed by the metallic centre and the capability of L to present various coordination links, it has been obtained complexes with square planar (1 and 3) or tetrahedral (2) geometry and different nuclearity: monomeric (1 and 2) or dimeric (3). Complete characterisation by analytical and spectroscopic methods, resolution of L and 1-3 by single-crystal X-ray diffraction and magnetic studies for complex 3 are presented.  相似文献   

8.
1H-Pyrrolo[2′,3′:4,5]furo[3,2-c]pyridine-2-carboxylic acid (6a) and its 1-methyl (6b) and 1-benzyl (6c) derivatives were synthesized. 3-(5-Methoxycarbonyl-4H-furo[3,2-b]-pyrrole-2-yl)propenoic acid (1) was converted to the corresponding azide 2, which in turn was cyclized to give 3 by heating in diphenylether. The pyridone 3 obtained was aromatized with phosphorus oxychloride, then reduced with zinc in acetic acid to give methyl 1H-pyrrolo[2′,3′:4,5]furo[3,2-c]pyridine-2-carboxylate (5), which by hydrolysis gave the corresponding carboxylic acid 6a.  相似文献   

9.
Reaction of the ligands 3-phenyl-5-(2-pyridyl)pyrazole (HL1), 3,5-bis(2-pyridyl)pyrazole (HL2), 3-methyl-5-(2-pyridyl)pyrazole (HL3) and 3-methyl-5-phenylpyrazole (HL4) with [MCl2(CH3CN)2] (M = Pd(II), Pt(II)) or [PdCl2(cod)] gives complexes with stoichiometry [PdCl2(HL)2] (HL = HL1, HL2, HL3), [Pt(L)2] (L = L1, L2, L3) and [MCl2(HL4)2] (M = Pd(II), Pt(II)). The new complexes were characterised by elemental analyses, conductivity measurements, infrared and 1H NMR spectroscopies. The crystal and molecular structure of [PdCl2(HL1)] was resolved by X-ray diffraction, and consists of monomeric cis-[PdCl2(HL1)] molecules. The palladium centre has a typical square planar geometry, with a slight tetrahedral distortion. The tetra-coordinated metal atom is bonded to one pyridine nitrogen, one pyrazolic nitrogen and two chloro ligands in a cis disposition. The ligand HL1 is not completely planar.  相似文献   

10.
In our efforts to investigate the relationships between the structures of ligands and their complexes, two structurally related ligands, 1-(2-pyridylmethyl)-1H-benzimidazole (L1) and 1-(4-pyridylmethyl)-1H-benzimidazole (L2), and their four complexes, [Zn(L1)2Cl2] (1), [Hg(L1)Br2] (2), {[Zn(L2)Cl2](CH3CN)} (3) and [Hg(L2)Br2]2(CH3CN)2 (4) were synthesized and structurally characterized by elemental analyses, IR spectra and single-crystal X-ray diffraction analysis. Structural analyses show that 1 has a mononuclear structure, and 2 and 3 both take 1D structure. While 4 takes a dinuclear structure. 1, 2 and 4 were further linked into higher-dimensional supramolecular networks by weak interactions, such as C-H?Cl and C-H?Br H-bonding, C-H?π, and π?π stacking interactions. The structural differences of 1-4 may be attributed to the difference of the spatial positions of the terminal N donor atoms in the pendant pyridyl groups in L1 and L2, in which the pyridine rings may act as the directing group for coordination and the benzimidazole rings act as the directing group for π?π stacking and C-H?π interactions. The luminescent properties of the corresponding complexes and ligands have been further investigated.  相似文献   

11.
A series of flexible dithioethyl ligands that contain ethyleneoxy segments were designed and synthesized, including bis(2-(pyridin-2-ylthio)ethyl)ether (L1), 1,2-bis(2-(pyridin-2-ylthio)ethoxy)ethane (L2), bis(2-(benzothiazol-2-ylthio)ethyl)ether (L3) and 1,2-bis(2-(benzothiazol-2-ylthio)ethoxy)ethane (L4). Reactions of these ligands with AgNO3 led to the formation of four new supramolecular coordination complexes, [Ag2L1(NO3)2]2 (1), [Ag2L2(NO3)2] (2), [AgL3(NO3)] (3) and [AgL4(NO3)] (4) in which the length of the (CH2CH2O)n spacers and the terminal groups of ligands cause subtle geometrical differences. Studies of the inhibitory effect to the growth of Phaeodactylum tricornutum show that all four complexes are active and the compound 4 has the highest inhibitory activity.  相似文献   

12.
The dinuclear complex [Cu2(L1)2(H2tea)2] (1) as well as the linear trinuclear complexes [Cu3(L1)4(H2tea)2] (2), [Cu3(L2)4(H2tea)2] (3) and [Cu3(L1)2(H2tea)2(NO3)2] (4) where L1 = 2-thiophene carboxylato, L2 = 2-thiophene acetato and H2tea = the single deprotonated form of triethanolamine have been prepared and pharmacochemically studied. The crystal structure of 1 is also reported. In vitro antioxidant activity of free ligands and their respective copper complexes includes: a) interaction with 1,1-diphenyl-2-picrylhydrazyl stable free radical, b) the ΗΟ˙ mediated oxidation of DMSO, c) scavenging of superoxide anion radicals, d) inhibition of lipid peroxidation and e) soybean lipoxygenase inhibition. The results indicate selectivity of the complexes to different free radicals as a consequence of their physichochemical features. The majority of the complexes 1, 2, 3, 4 effectively inhibit lipid peroxidation. The trinuclear complex 3 is by far the most active with IC50 = 10 μM, within the set, followed by complexes 1 and 2. The complexes were evaluated for their efficacy as anticancer agents against different cancer and normal human cell lines. Results showed that, these compounds mediate a moderate cytotoxic response to normal and cancer cell lines tested and induce cell cycle arrest in G2/M phase of the cell cycle. Flow cytometric analysis suggested that the tested compounds can induce apoptosis.  相似文献   

13.
The coordination chemistry of the ligand bis[2-(3,5-dimethyl-1-pyrazolyl)ethyl]ether (L1) was tested in front of Pd(II) and Pt(II). Complexes cis-[MCl2(L1)] (M=Pd(II) and Pt(II)) were obtained, due to the chelate condition of the ligand and the formation of a stable 10-membered ring. The crystal structure of cis-[PtCl2(L1)] was resolved by X-ray diffraction. Treatment of [PdCl2(L1)] or [Pd(CH3CN)4](BF4)2 with AgBF4 in the presence of L1 gave the complex [Pd(L1)2](BF4)2. The initial cis-[PdCl2(L1)] was recovered by reacting [Pd(L1)2](BF4)2 with an excess of NEt4Cl. Reaction of [Pt(CH3CN)4](BF4)2 (generated in situ from [PtCl2(CH3CN)2] and AgBF4 in acetonitrile) with ligand L1 yields complex [Pt(L1)2](BF4)2.  相似文献   

14.
The reaction of 1-(2-hydroxyethyl)-3,5-dimethylpyrazole (HL) with anhydrous metal(III) halides (M = Al, Ga, In and Cr) results in the isolation of four novel dinuclear complexes [Al(μ-L)Cl2]2 (1), [Ga(μ-L)Cl2]2 (2), [In(μ-L)Br2(H2O)]2·2thf (3) and [Cr(μ-L)Cl2(H2O)]2·1.5thf (4) in good yields. The new complexes have been characterized with the aid of analytical and spectroscopic studies. A single crystal X-ray structure determination in each case confirms the dimeric structure for all the complexes in the solid-state. The pyrazole ethanol ligand binds to the metal through both pyrazole nitrogen and bridging alkoxide oxygen terminals with the formation of a central M2O2 core involving the ethoxide anion. The metal(III) center is pentacoordinated in compounds 1 and 2, while it is hexacoordinated in compounds 3 and 4.  相似文献   

15.
The synthesis and characterisation of two dicopper(II) and two dinickel(II) macrocyclic complexes, [CuII2LPr] (10), [CuII2LBu] (11), [NiII2LPr] (12) and [NiII2LBu] (13), are reported. The two new Schiff-base macrocycles (LPr)4− and (LBu)4− are isolated as dimetallic complexes 10-13 by the [2+2] condensation of 5,5-dimethyl-1,9-diformyldipyrromethane (9) and 1,3-diaminopropane or 1,4-diaminobutane, respectively, using Cu2+ or Ni2+ template ions. Single crystal X-ray structure determinations carried out on 10-13 show that each metal atom is in a square planar N4 geometry, being bound to two deprotonated pyrrole nitrogen atoms of one dipyrromethane unit and to the two adjacent imine nitrogen atoms. NMR spectra obtained for the two dinickel(II) complexes 12 and 13 show that in CDCl3 solution they are highly symmetrical and diamagnetic.  相似文献   

16.
Five new complexes [Cu2(L1)I2] (1), [Cu(L2)I]2 (2), {[Cu2(L2)I2](CH3CN)3} (3), [Cu2(L3)I2] (4) and {[Cu(L3)I](CH3CN)}2 (5) have been obtained by reacting three structurally related ligands, 2,3-bis(n-propylthiomethyl)quinoxaline (L1), 2,3-bis(tert-butylthiomethyl)quinoxaline (L2) and 2,3-bis[(o-aminophenyl)thiomethyl]quinoxaline (L3) with CuI, respectively, at different temperatures. Single crystal X-ray analyses show that 1, 3, 4 possess 1D chain structures, while 2 and 5 are discrete dinuclear molecules. It is interesting that the reactions of CuI with L1 at room temperature and 0 °C, respectively, only afforded same structure of 1 (1a and 1b), while using L2 (or L3) instead, two different frameworks 2 and 3 (or 4 and 5) have been obtained. The structural changes mainly resulted from the different conformations that L2 or L3 adopted at different temperatures. Our research indicates that terminal groups of ligands take an essential role in the framework formation, and the reaction temperature also has important effect on the construction of such Cu(I) coordination architectures. Furthermore, the influence of hydrogen bonds on the conformation of ligands and the supramolecular structures of these complexes have also been explored. The luminescence properties of complexes 1, 2, and 4 have been studied in solid state at room temperature.  相似文献   

17.
《Inorganica chimica acta》2002,327(1):169-178
New complexes [MI(CO)2(dppe){S2P(OEt)2}] (M=W, 1a; M=Mo, 1b), [MI(CO)2(dppm){S2P(OEt)2}] (M=W, 2a; M=Mo, 2b) and [W(CO)(dppe){S2P(OEt)2}2][O2dppe] (3a), were synthesised from [MI2(CO)3(NCMe)2] (M=Mo, W), after treatment with ammonium diethyldithiophosphate and phosphine under different conditions. The structure of the tungsten complexes was determined by single crystal X-ray diffraction. During the synthesis of 3a, oxidation of the phosphine took place and a molecule of oxidised phosphine occupies channels in the crystal. DFT/B3LYP calculations on models of 1a and 2a showed the capped octahedron structure, observed in most dicarbonyl complexes of this family, to be preferred by 1.4 and 2.6 kcal mol−1 for the dppm and the dppe complexes, respectively. Strong steric repulsions can reverse this trend, as happens with the rigid dppm ligand. Complex 1a adopts a pentagonal bipyramidal geometry, which is often found in related monocarbonyl complexes.  相似文献   

18.
The reaction of 1-methyl-3-(2-propenyl)imidazolium bromide (1) or 1,3-bis(2-propenyl)-imidazolium bromide (2) with [Ir(μ-OMe)(cod)]2 afforded the five coordinated iridium(I) carbene complexes [IrBr(L)(cod)] (3) (L=1-methyl-3-(2-propenyl)imidazolin-2-ylidene) and (4) (L=1,3-bis(2-propenyl)imidazolin-2-ylidene). The reaction proceeds via an in situ deprotonation of the imidazolium salt. Molecular structure determinations on 3 and 4 confirmed the coordination of the carbene ligands via the carbene carbon atom and one allyl group in both complexes. Treatment of complex 3 with an excess of AgBF4 gave the dinuclear bromo bridged complex [(Ir(μ-Br)(L)(cod)]2BF4 (5) (L=1-methyl-3-(2-propenyl)imidazolin-2-ylidene). The reaction of complex 4 with an excess of AgBF4 led to the mononuclear complex [Ir(L)(cod)]BF4 (6) (L=1,3-bis(2-propenyl)imidazolin-2-ylidene) where both N-allyl substituents are coordinated to the iridium(I) center.  相似文献   

19.
Bis-bidentate Schiff base ligand L and its two mononuclear complexes [CuL(CH3CN)2]ClO4 (1) and [CuL(PPh3)2]ClO4 (2) have been prepared and thoroughly characterized by elemental analyses, IR, UV-Vis, NMR spectroscopy and X-ray diffraction analysis. In both the complexes the metal ion auxiliaries adopt tetrahedral coordination environment. Their reactivity, electrochemical and photophysical behavior have been studied. Complex 1 shows reversible CuII/I couple with potential 0.74 V versus Ag/AgCl in CH2Cl2. At room temperature L is weakly fluorescent in CH2Cl2, however in Cu(I) complexes 1 and 2 the emission in quenched.  相似文献   

20.
Reaction of the potassium salts of (EtO)2P(O)CH2C6H4-4-(NHC(S)NHP(S)(OiPr)2) (HLI), (CH2NHC(S)NHP(S)(OiPr)2)2 (H2LII) or cyclam(C(S)NHP(S)(OiPr)2)4 (H4LIII) with [Cu(PPh3)3I] or a mixture of CuI and Ph2P(CH2)1-3PPh2 or Ph2P(C5H4FeC5H4)PPh2 in aqueous EtOH/CH2Cl2 leads to [Cu(PPh3)LI] (1), [Cu2(Ph2PCH2PPh2)2LII] (2), [Cu{Ph2P(CH2)2PPh2}LI] (3), [Cu{Ph2P(CH2)3PPh2}LI] (4), [Cu{Ph2P(C5H4FeC5H4)PPh2}LI] (5), [Cu2(PPh3)2LII] (6), [Cu2(Ph2PCH2PPh2)LII] (7), [Cu2{Ph2P(CH2)2PPh2}2LII] (8), [Cu2{Ph2P(CH2)3PPh2}2LII] (9), [Cu2{Ph2P(C5H4FeC5H4)PPh2}2LII] (10), [Cu8(Ph2PCH2PPh2)8LIIII4] (11), [Cu4{Ph2P(CH2)2PPh2}4LIII] (12), [Cu4{Ph2P(CH2)3PPh2}4LIII] (13) or [Cu4{Ph2P(C5H4FeC5H4)PPh2}4LIII] (14) complexes. The structures of these compounds were investigated by IR, 1H, 31P{1H} NMR spectroscopy; their compositions were examined by microanalysis. The luminescent properties of the complexes 1-14 in the solid state are reported.  相似文献   

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