首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
The complexes [Mn(L1)(tcc)] (1), [Mn(L2)(tcc)] · H2O · 0.5CH3OH (2), [Mn(L3)(tcc)] · CH2Cl2 (3), [Mn(L4)(tcc)] · 1.5CH2Cl2 (4), [Mn(L5)(tcc)] (5), and (HN(C2H5)3)[Mn(L6)(tcc)] · CH2Cl2 (6) have been synthesized using the ligands HL1 (2-[(bis(pyridin-2-ylmethyl)amino)methyl]phenol), HL2 (2-[[((6-methylpyridin-2-yl)methyl)(pyridin-2-ylmethyl)amino]methyl] phenol), HL3 (2-[[((6-methylpyridin-2-yl)methyl)(pyridin-2-ylmethyl)amino]methyl]-4-nitrophenol), HL4 (2-[(bis(pyridin-2-ylmethyl)amino)methyl]-4-bromophenol), HL5 (2-[(bis(pyridin-2-ylmethyl)amino)methyl]-6-methoxyphenol) and H2L6 ([(bis(2-hydroxy-5-nitrobenzyl))(pyridin-2-ylmethyl)]amine) and characterized by X-ray crystallography, mass spectrometry, IR, UV-Vis spectroscopy, cyclic voltammetry, and elemental analysis. Compounds 1 and 6 crystallize in the monoclinic space groups P21/n and P21/c, respectively, whereas the crystal structures of complexes 2, 3, and 4 were solved in the triclinic space group . Complex 5 crystallizes in the orthorhombic space group P212121. Complexes 1-6 are structural related to the proposed active site of intradiol cleaving catechol dioxygenase exhibiting a distorted octahedral N3O3 (1-5) and N2O4 (6) donor set, respectively. Complexes 1-6 can be regarded as structural manganese analogous for substituted forms of iron-containing intradiol cleaving catechol dioxygenases, where the substrate tetrachlorocatechol (tcc) is asymmetrically bound to the metal center.  相似文献   

2.
The orange-red colored complexes of the type [Fe(LSB)Cl3], 1, have been synthesized in excellent yields by reacting FeCl3·6H2O with LSB in methanol. Here, LSB is (2-(ethylthio)-N-(pyridin-2-ylmethyl)ethanamine), (LSB1) and (2-(benzylthio)-N-(pyridin-2-ylmethyl)ethanamine) (LSB2). Similarly, FeCl3·6H2O reacted with 2-(((2-(ethylthio) ethyl) (pyridin-2-ylmethyl)amino)methyl)phenol (HL1), 2-(((2-(ethylthio)ethyl)(pyridin-2 ylmethyl)amino)methyl)-4-nitrophenol (HL2), 4-chloro-2-(((2-(ethylthio)ethyl)(pyridin-2-ylmethyl)amino)methyl)phenol (HL3), 2-(((2-(benzylthio)ethyl)(pyridin-2-ylmethyl) amino)methyl)phenol (HL4), 2-(((2-(benzylthio)ethyl)(pyridin-2-ylmethyl)amino)methyl) -4-nitrophenol (HL5), and 4-chloro-2-(((2-(benzylthio)ethyl)(pyridin-2-ylmethyl)amino) methyl)phenol (HL6) to give dichloro complexes of the type [Fe(L)Cl2], 2. The solid and solution structure of the complexes, as well as their properties, were probed using X-ray diffraction, spectroscopic and electrochemical methods. The Mössbauer spectral study at 80 K for complexes reveals the existence of (III) oxidation state and high-spin state of the metal center in the complex. Dioxygenase activity of the complexes has been studied and both 1 and 2 have been found to display the intradiol-cleaving pathway. However, no extradiol cleavage products have been isolated.  相似文献   

3.
Syntheses and crystal structures of tren-based amide, L1, N,N′,N″-tris[(2-amino-ethyl)-4-nitro-benzamide] and L2, N,N′,N″-tris[(2-amino-ethyl)-2-nitro-benzamide] are reported and compared with previously published tripodal amide receptor L3, N,N′,N″-tris[(2-amino-ethyl)-3-nitro-benzamide]. The crystallographic results show intramolecular and intermolecular hydrogen-bonding interactions between two arms of the tripodal receptor and two other adjacent molecules in cases of L1 and L2 whereas in addition to the above interactions an aromatic π···π stacking among tripodal arms is also observed in L3. Receptors L1, L2 and L3 having electron withdrawing -NO2 substituted (para, ortho and meta, respectively) phenyl moieties are explored toward their solution state anion binding properties and selectivity studies. The substantial changes in chemical shifts are observed for the amide protons (-NH) and aromatic protons (-CH) with F and Cl in cases of L1 and L3, and only with F for L2, indicating the participation of -NH and -CH protons in the solution state binding events. Binding constants for the above cases are calculated by 1H NMR titration upon monitoring the -NH signal. Receptor L2 shows exclusive selectivity toward F in dimethyl sulfoxide (DMSO). The structural aspects of binding I, ClO4 and SiF62− with the monoprotonated L1, L1H+·I·DMF (1), L1H+·ClO4·DMF (2) and L1H+·0.5SiF62−·H2O (3), respectively are examined crystallographically. Anion binding with multiple receptor units is observed via amide N-H···anion as well as aryl C-H···anion hydrogen-bonding interactions in all the complexes as observed in cases of previously reported crystal structures of anionic complexes of protonated L3. The aryl group having nitro functionality that contributes to solution state anion binding with the neutral receptor and solid state coordination in complexes 1-3 through CH···anion interactions is noteworthy.  相似文献   

4.
Four novel nicotinato-copper(II) complexes containing polybenzimidazole and polyamine ligands were synthesized with formula [Cu2(bbma)2(nic)2](ClO4)2·CH3OH·0.5H2O (1), [Cu2(dien)2(nic)2](ClO4)2·2CH3OH (2), [Cu(ntb)(nic)]ClO4·H2O (3) and [Cu(tren)(nic)]BPh4·CH3OH·H2O (4), in which bbma is bis(benzimidazol-2-yl-methyl)amine, dien is diethylenetriamine, ntb is tris(2-benzimidazolylmethyl)amine, tren is tris(2-aminoethyl)amine and nic is nicotinate anion. All of the complexes were characterized by elemental analysis, IR and X-ray diffraction analysis. Complexes 1 and 2 contain centrosymmetric dinuclear entity with the two Cu(II) atoms bridged by two nicotinate anions in an anti-parallel mode. The Cu···Cu separation is 7.109 Å for 1 and 6.979 Å for 2. Complexes 3 and 4 are mononuclear with nicotinate coordinated to Cu(II) ion by the carboxylate O atom in 3 and the pyridine N atom in 4. All of the complexes exhibit abundant hydrogen bonds to form 1D chain for 1, 3, 4 and 2D network for 2. Magnetic susceptibility measurements over the 2-300 K range reveal very weak ferromagnetic interaction between the two Cu(II) ions in 1 and antiferromagnetic interaction in 2 mediated by nicotinate ligand, with J value to be 0.15 and −0.19 cm−1, respectively.  相似文献   

5.
Two new manganese(II) complexes, [Mn(L1)(L1H)(ClO4)(H2O)][ClO4]2·0.5CH3CN·H2O (1) [L1 = trans-(±)2-(2,5-di(pyridin-2-yl)-4,5-dihydro-1H-imidazol-4-yl)pyridine)] and [Mn2(μ-L2)2(H2O)3(CH3CN)3][ClO4]4·2CH3CN (2) [L2 = cis-(±)2-(2,5-di(pyridin-2-yl)-4,5-dihydro-1H-imidazol-4-yl)pyridine)], have been prepared and examined by single-crystal X-ray diffraction analysis, showing that complex 1 is a mononuclear compound, whereas complex 2 is a dinuclear species. The cis/trans isomers L1 and L2 have similar coordination properties, but behave as bidentate and tridentate chelating ligands, respectively, giving distorted octahedral metal coordination geometries. X-ray diffraction studies revealed that the molecular and crystal structures are stabilized by a series of intra- and intermolecular interactions. In both cases extended supramolecular networks are generated, in compound 1 through O-H···O, O-H···N, N-H···O, N-H···N, C-H···O, C-H···N, C-H···π and π···π interactions, and in compound 2 through O-H···O, O-H···N, C-H···O and π···π interactions. The observed structural differences between the two metal complexes might be a consequence of these stabilizing effects.  相似文献   

6.
The complexes of Cu(I), Cu(II), Ni(II), Zn(II) and Co(II) with a new polypyridyl ligand, 2,3-bis(2-pyridyl)-5,8-dimethoxyquinoxaline (L), have been synthesized and characterized. The crystal structures of these complexes have been elucidated by X-ray diffraction analyses and three types of coordination modes for L were found to exist in them. In the dinuclear complex [Cu(I)L(CH3CN)]2·(ClO4)2 (1), L acts as a tridentate ligand with two Cu(I) centers bridged by two L ligands to form a box-like dimeric structure, in which each Cu(I) ion is penta-coordinated with three nitrogen atoms and a methoxyl oxygen atom of two L ligands, and an acetonitrile. In [Cu(II)L(NO3)2]·CH3CN 2, the Cu(II) center is coordinated to the two nitrogen atoms of the two pyridine rings of L which acts as a bidentate ligand. The structures of [Ni(II)L(NO3)(H2O)2]·2CH3CN·NO3 (3), [Zn(II)L(NO3)2 (H2O)]·2CH3CN (4) and [Co(II)LCl2(H2O)] (5) are similar to each other in which L acts as a tridentate ligand by using its half side, and the metal centers are coordinated to a methoxyl oxygen atom and two bipyridine nitrogen atoms of L in the same side. The formation of infinite quasi-one-dimensional chains (1, 4 and 5) or a quasi-two-dimensional sheet (2) assisted by the intra- or intermolecular face-to-face aryl stacking interactions and hydrogen bonds may have stabilized the crystals of these complexes. Luminescence studies showed that 1 exhibits broad, structureless emissions at 420 nm in the solid state and at 450 nm in frozen alcohol frozen glasses at 77 K. Cyclic voltammetric studies of 1 show the presence of an irreversible metal-centered reduction wave at approximately −0.973 V versus Fc+/0 and a quasi-reversible ligand-centered reduction couple at approximately −1.996 V versus Fc+/0. The solution behaviors of these complexes have been further studied by UV-Vis and ESR techniques.  相似文献   

7.
Two oxime-functionalized diazamesocyclic derivates, namely, N,N′-bis(acetophenoneoxime)-1,4-diazacycloheptane (H2L1) and N,N′-bis(acetophenonoxime)-1,5-diazacyclooctane (H2L2), have been prepared and characterized. Both ligands (obtained in the hydrochloride form) can form stable metal complexes with CuII and NiII salts, the crystal structures of which were determined by X-ray diffraction technique. The reactions of H2L1 with Cu(ClO4)2 and Ni(ClO4)2 afford a penta-coordinated mononuclear complex [Cu(H2L1)Cl] · ClO4 (1) and a four-coordinated monomeric [Ni(HL1)] · ClO4 (2), in which the ligand is monodeprotonated. The ligand H2L2 also forms a quite similar mononuclear [Ni(HL2)] · ClO4 complex with Ni(ClO4)2, according to our previous work. However, reactions of different CuII salts [Cu(ClO4)2, CuCl2 and Cu(NO3)2 for 3, and CuSO4 for 4] with H2L2 in the presence of NaClO4 yield two unusual mono-μ-Cl dinuclear CuII complexes [Cu2(HL2)2Cl] · (ClO4) (3), and [Cu2(H2L2)(HL2)Cl] · (ClO4)2 · (H2O)(4). These results indicate that the resultant CuII complexes (1, 3 and 4) are sensitive to the backbones of diazamesocycles and even auxiliary anions.  相似文献   

8.
The synthesis of two new sodium perchlorate adducts (1:2 and 1:3) with copper(II) “ligand-complexes” is reported. One adduct is trinuclear [(CuL1)2NaClO4] (1) and the other is tetranuclear [(CuL2)3Na]ClO4·EtOH (2). The ligands are the tetradentate di-Schiff base of 1,3-propanediamines and salicylaldehyde (H2L1) or 2-hydroxyacetophenone (H2L2). Both complexes have been characterized by X-ray single crystal structure analyses. In both structures, the sodium cation has a six-coordinate distorted octahedral environment being bonded to four oxygen atoms from two Schiff-base complexes in addition to a chelated perchlorate anion in 1 and to six oxygen atoms from three Schiff-base complexes in 2. We have carried out a DFT theoretical study (RI-B97-D/def2-SVP level of theory) to compute and compare the formation energies of 1:2 and 1:3 adducts. The DFT study reveals that the latter is more stabilized than the former. The X-ray crystal structure of 1 shows that the packing of the trinuclear unit is controlled by unconventional C-H···O H-bonds and Cu2+-π non-covalent interactions. These interactions explain the formation of 1 which is a priori disfavored with respect to 2.  相似文献   

9.
A series of new binuclear copper (II) and nickel (II) complexes of the macrocyclic ligands bis(1,4,7-triazacyclononan-1-yl)butane (Lbut) and bis(1,4,7-triazacyclononan-1-yl)-m-xylene (Lmx) have been synthesized: [Cu2LbutBr4] (1), [Cu2Lbut(imidazole)2Br2](ClO4)2 (2), [Cu2Lmx(μ-OH)(imidazole)2](ClO4)3 (3), [Cu2Lbut(imidazole)4](ClO4)4 · H2O (4), [Cu2Lmx(imidazole)4](ClO4)4 (5), [Ni2 Lbut(H2O)6](ClO4)4 · 2H2O (6), [Ni2Lbut(imidazole)6](ClO4)4 · 2H2O (7) and [Ni2Lmx (imidazole)4(H2O)2](ClO4)4 · 3H2O (8). Complexes 1, 2, 7 and 8 have been characterized by single crystal X-ray studies. In each of the complexes, the two tridentate 1,4,7-triazacyclononane rings of the ligand facially coordinate to separate metal centres. The distorted square-pyramidal coordination sphere of the copper (II) centres is completed by bromide anions in the case of 1 and/or monodentate imidazole ligands in complexes 2, 4 and 5. Complex 3 has been formulated as a monohydroxo-bridged complex featuring two terminal imidazole ligands. Complexes 6-8 feature distorted octahedral nickel (II) centres with water and/or monodentate imidazole ligands occupying the remaining coordination sites. Within the crystal structures, the ligands adopt trans conformations, with the two metal binding compartments widely separated, perhaps as a consequence of electrostatic repulsion between the cationic metal centres. The imidazole-bearing complexes may be viewed as simple models for the coordinative interaction of the binuclear complexes of bis (tacn) ligands with protein molecules bearing multiple surface-exposed histidine residues.  相似文献   

10.
The nickel(II) complexes of the compositions [Ni(hmidtc)(bpy)2]ClO4 (I), [Ni(hmidtc)(phen)2]ClO4 (II), [Ni(hmidtc)(phen)2]SCN (III), [Ni(hmidtc)(phen)2]PF6 (IV), [Ni(hmidtc)(phen)2]BPh4 (V), [Ni(hmidtc)(phen)2]AcO·2H2O (VI) and [Ni(hmidtc)(phen)2]Br·H2O (VII), involving a combination of one hexamethyleneimine-dithiocarbamate anion (hmidtc) and two bidentate N,N-donor ligands (2,2′-bipyridine (bpy) for I or 1,10-phenanthroline (phen) for II-VII), have been prepared. The compounds were characterized by elemental analysis, molar conductivity measurements, UV-Vis and IR spectroscopy, magnetochemical measurements and thermal analysis. A single-crystal X-ray analysis of the complex I revealed a distorted octahedral geometry with the nickel(II) ion coordinated by four nitrogen atoms (from two bidentate-coordinated bpy molecules) and two sulfur atoms (from one bidentate-coordinated hmidtc anion), together giving an NiN4S2 donor set.  相似文献   

11.
Two new ligand-containing histidine based on N,N′,N″-tris(N-benzyl-l-histidinyl)tri(2-aminoethyl)amine, L1, namely N,N′,N″-tris[(1S)-2-methoxy-2-oxy-1-(1-benzylimidazol-4-ylmethyl)]nitrilotriacetamide L2 and N,N′,N″-tris{N-benzyl-N-[N-benzyl-N-(N-benzyl-l-histidinyl)-l-histidinyl]-l-histidinyl}tri(2-aminoethyl)amine L3 were prepared. Zinc(II) binding studies by these ligand systems were analyzed by means of potentiometric and 1H NMR titrations in aqueous methanol (33 % v/v). Subsequently their zinc(II) complexes [L1Zn(H2O)](ClO4)2·HClO4 (1), [L2Zn(OH2)](ClO4)2·H2O (2), and ([L3Zn3(H2O)3](ClO4)6·3HClO4·5H2O (3), respectively were synthesized and characterized. The reactivity of the trinuclear complex (3) toward the hydrolysis of the toxic organophosphate parathion was investigated and compared with that of the mononuclear reference complex (1). From the pH dependence of the apparent rate constants, and the deprotonation constant (pKa) of the coordinated water molecules in (1), the active species were confirmed to be {[HL1Zn(OH)]2+/[L1Zn(H2O)]2+} at pH 8.5. The trizinc complex (3) effects hydrolysis of parathion, with three times rate enhancement over the mononuclear (1), indicating that cooperative action of the three zinc centers is limited.  相似文献   

12.
Two new nickel(II) complexes with the composition [Ni(L+H)(CH3CN)2](ClO4)3 (1) and [Ni(L)(tp)]·6H2O (2), (L = 3,10-bis{3-(1-imidazolyl)propyl}-1,3,5,8,10,12-hexaazacyclotetradecane, tp = terephthalate) have been synthesized and structurally characterized by a combination of analytical, spectroscopic and X-ray diffraction methods. The structure of 1 consists of monomeric cations of the formula [Ni(L+H)(CH3CN)2]3+ and perchlorate ions. The nickel(II) ion is six-coordinate with bonds to the four nitrogen atoms of the macrocycle and two nitrogen atoms of the axial acetonitrile ligands. One of the protonated imidazole pendants of the macrocycle is hydrogen bonded to the imidazole group of the neighboring nickel(II) macrocycle, forming an undulated 1D supramolecule. Then, the two 1D supramolecular chains are further interconnected by C-H···π interactions between the methyl group of the acetonitrile ligand and one of the imidazole groups to form a 2D double stranded supramolecular polymer. In the structure of 2, the 1D coordination polymer is formed with nickel(II) macrocycles and bridging terephthalate ions, where each 1D chain is interconnected with π-π interactions of pendant imidazole moieties of the macrocycles, resulting in the formation of a 2D supramolecule.  相似文献   

13.
Novel cobalt(III) complexes containing three kinds of assembled ligands, L1L2=dapymt-tbba(2-), tbba-dapymt(1-) and apymt-tbba(1-) (H3tbba=thiobarbituric acid; Hdapymt=4,6-diamino-2-thiouracil; Hapymt=4-amino-2-thiouracil), were prepared from the mixed ligand systems, where L2 indicates the coordinated ligand to the Co(III) ion and L1 is a pendant ligand bonded to L2. These complexes were characterized by UV-Vis absorption spectra and NMR spectroscopy. The crystal structures of [Co(Htbba)(en)2]ClO4·2H2O (2) (en=ethane-1,2-diamine), [Co{dapymt-tbba(2-)}(en)2]ClO4·3H2O (3) and [Co{apymt-tbba(1-)}(en)2](ClO4)Cl·3H2O (5′) revealed that coordination occurs through the S(1) and N(1) donors of tbba and the latter complexes 3 and 5′ have an assembled ligand; a new bond is formed between the C(5) atom of tbba and the S(2) atom of dapymt or apymt. An intramolecular hydrogen bond between O(1) of tbba and NH of en was found in all crystals. An interesting intermolecular π-π stacking interaction was found in 5′.  相似文献   

14.
In order to further understand the coordination chemistry of diazamesocyclic systems, a series of mononuclear NiII complexes with 1,4-diazacycloheptane (DACH) functionalized by additional imidazole or pyridine donor pendants, including [NiL1](ClO4)2 · H2O (1), [NiL1Cl](ClO4) (2), [NiL2Cl](ClO4) · CH3OH (3), [NiL2Cl][NiL2](ClO4)3 (4) and [NiL3](ClO4)2 (5), where L1 = 1,4-bis(N-1-methylimidazol-2-yl-methyl)-1,4-diazacycloheptane, L2 = 1,4-bis(pyridyl-2-yl-methyl)-1,4-diazacycloheptane, and L3 = 1,4-bis-(imidazol-4-yl-methyl)-1,4-diazacycloheptane, have been prepared and characterized. A detailed study on the solid structures and solution spectra of these complexes indicates that tetradentate ligands L1, L2 and L3 would lead to new NiII complexes with different coordination environments in the solid states and solution. The N-methyl substituted imidazole functionalized ligand L1 forms green compound 2 and yellow product 1; while the pyridine functionalized ligand L2 affords red product 4 and green complex 3; the ligand L3 results in only one stable mononuclear NiII product 5. The solution behaviors of these interesting compounds were also investigated by UV-Vis technique.  相似文献   

15.
When the complexes [Cu(L1)(H2O)](ClO4)21, where L1 = 4-methyl-1-(pyrid-2-ylmethyl)-1,4-diazacycloheptane, and [Cu(L2)Cl2] 2, where L2 = 4-methyl-1-(quinol-2-ylmethyl)-1,4-diazacycloheptane are interacted with one/two equivalents of bis(p-nitrophenylphosphate, (p-NO2Ph)2PO2, BNP), no hydrolysis of BNP is observed. From the solution the adducts of copper(II) complexes [Cu2(L1)2((p-NO2Ph)2PO2)2]-(ClO4)23 and [Cu(L2)((p-NO2Ph)2PO2)2]·H2O 4 have been isolated and structurally characterised. The X-ray crystal structure of 3 contains two Cu(L1) units bridged by two BNP molecules. The Cu···Cu distance (5.1 Å) reveals no Cu-Cu interaction. On the other hand, the complex 4 is mononuclear with Cu(II) coordinated to the 3N ligand as well as BNP molecules through phosphate oxygen. The trigonality index (τ, 0.37) observed for 4 is high suggesting the presence of significant trigonal distortion in the coordination geometry around copper(II). The complexes are further characterized by spectral and electrochemical studies.  相似文献   

16.
Two trinuclear copper(II) complexes of a Schiff-base type N4O-donor ligand (LH) derived from 4,4,9,9-tetramethyl-5,8-diazadodecane-2,11-dione and 1,3-diaminopropan-2-ol are reported. Complex [Cu3L2(ClO4)4] (1) has an angular C2-symmetric trinuclear core as revealed from single-crystal X-ray diffraction studies. The terminal coppers are in square-pyramidal geometry with an N3O2 coordination environment while the central one is in octahedral geometry with an N2O4 donor environment. Complex [Cu3L2(ClO4)(N3)(H2O)](ClO4)2 · H2O (2) has an unsymmetrical trinuclear core with an intramolecular hydrogen bonding interaction between the water and azide anion coordinated to Cu(1) and Cu(3) center, respectively. All the copper centers in 2 are in square-pyramidal geometry. The average Cu?Cu distance between closest metal ions in both the complexes is 3.897 Å. The coordination environment of coppers in 1 approximately mimics that of multicopper oxidases in the oxidized form and the environment in 2 mimics that of the azide derivative of ascorbate oxidase. Both 1 and 2 exhibit doublet spin ground state due to strong antiferromagnetic coupling operating through the alkoxo-bridged oxygen atoms between the copper centers.  相似文献   

17.
Two new linear and V-shaped tetradentate ligands, namely 1,4-bis(2-hexahydropyrimidyl)benzene (L) and 1,3-bis(2-hexahydropyrimidyl)benzene (L), and their silver(I) complexes, [Ag2L(μ-ONO2)](NO3) · 2H2O (1), [Ag2L(μ-pn)](NO3)2 (2), [Ag2L(μ-pn)](ClO4)2 (3) and [Ag4L2(H2O)](NO3)4 · 5H2O (4) (pn=1,3-diaminopropane) have been synthesized in situ and structurally characterized by single-crystal X-ray diffraction. 1 and 2 were obtained from the same reaction solution but different crystallization conditions. 1 is an one-dimensional chain featuring cuboid tetranuclear silver(I) units interconnected through monoatomic nitrate bridges. Both 2 and 3 are ribbon-like helical compounds in which each L ligand acts in a tetradentate bridging mode to interconnect four metal atoms, and each pn ligand functions in a bidentate bridging mode to link a pair of metal atoms. 4 shows a truncated square-pyramidal tetranuclear motif arose by the V-shaped L ligand. Close Ag?Ag separations (2.901-2.939 Å) assisted by bis(hexahydropyrimidine) bridges were observed in 1 and 4, indicating metal-metal interactions. Photoluminescence of 1-4 has also been observed in the solid state and solution at room temperature and low temperature, respectively.  相似文献   

18.
Four new coordination complexes, NiII(L)2 (1), [CoIII(L)2]ClO4 (2), [Zn(HL)(L)]ClO4 · H2O (3) and [Zn(L)2][Zn(L)(HL)]ClO4 · 7H2O (4) (where L is a monoanion of a Schiff base ligand, N′-[(2-pyridyl)methylene]salicyloylhydrazone (HL) with NNO tridentate donor set), have been synthesised and systematically characterised by elemental analysis, spectroscopic studies and room temperature magnetic susceptibility measurements. Single crystal X-ray diffraction analysis reveals that 1 is a neutral complex, while 2-4 are cationic complexes. Among them, 4 is a rare type of cationic complex with two molecules in the asymmetric unit. The ligand chelates the metal centre with two nitrogen atoms from the pyridine and imino moieties and one oxygen atom coming from its enolic counterpart. All the reported complexes show distorted octahedral geometry around the metal centres, with the two metal-N (imino) bonds being significantly shorter than the two metal-N (Py) bonds.  相似文献   

19.
Four new coordination complexes [Cd(DPBA-3)2(H2O)2](ClO4)2·2H2O (1), [Cd(DPBA-3)(DMF)(NO3)2]·DMF (2), [Cd3(DPBA-3)2(SCN)6]·2DMF·4H2O (3) and [Zn(DPBA-3)(SCN)2] (4) [DPBA-3 = N,N′-di(pyridin-3-yl)pyridine-3,5-dicarboxamide] have been synthesized and characterized by elemental analysis, IR and single crystal X-ray diffraction. Complexes 1, 3 and 4 exhibit three different types of one-dimensional (1D) chain structures constructed by the metal ions and DPBA-3 ligands, and the Cd(II)-DPBA-3 1D chains in 3 are further linked by bridging SCN ligands to afford a three-dimensional (3D) framework. Complex 2 possesses a (6,3) two-dimensional (2D) layer structure. In 1-4, the hydrogen bonds involving the amide groups play important role to stabilize the resultant frameworks. The photoluminescence properties of the DPBA-3 and the complexes were studied in the solid state at room temperature.  相似文献   

20.
Compounds of the molecular formulae, [LH3](NO3)3 (1), [Fe(LH)2](PF6)4·5H2O (2), [Fe(L)2][Fe(L)(LH)](PF6)5·H2O (3), [Fe(L)2][Fe(L)(LH)](BF4)5·2H2O (4) and [Fe(L)2](Cr2O7)·6H2O (5) have been synthesized using 4′-(2-pyridyl)-2,2′:6′,2″-terpyridine (L). The molecular structures of all the compounds were determined. The Fe(II) complexes are high spin in nature at room temperature and upon cooling a gradual spin-transition is observed. Among 1-5, hydrogen-bonding, π···π, and anion···π interactions as well as water tetramer and pentamer are present in the molecular packing.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号