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1.
Bin Hu 《Inorganica chimica acta》2010,363(7):1348-6199
Four transition metal complexes of 3,8-di(thiophen-2′,2″-yl)-1,10-phenanthroline (dtphen), formulated as [Ni(dtphen)2(H2O)2]·(ClO4)2 (1), [Zn(dtphen)2(H2O)]·(ClO4)2 (2) [Cu(dtphen)2(H2O)]·(ClO4)2 (3), [Cu(dtphen)(phen)2]·(ClO4)2 (4) (phen = 1,10-phenanthroline) with different metal-to-ligand ratios, were synthesized and characterized herein. The X-ray single-crystal diffraction studies of 1-4 exhibit that different molecular configurations for the dtphen ligand can be observed where the side thiophene rings adopt the trans/trans, trans/cis, trans/disorder and cis/cis conformations relative to the central 1,10-phenanthroline unit in different compounds. Fluorescence emission spectra of 1-4 in methanol show that the fluorescence emission of 2 is much stronger than the other three metal complexes, which is mainly due to its full d10 electronic configuration of Zn(II) ion.  相似文献   

2.
A series of Ru(II) polypyridyl complexes [Ru(bpy)2(ptdb)](ClO4)2 (1), [Ru(bpy)2(ptda)](ClO4)2 (2) and [Ru(bpy)2(ptdp)](ClO4)2 (3) with asymmetric intercalative ligands have been synthesized and characterized by EA, mass spectra, 1H NMR and cyclic voltammetry. The crystal structure of complex 1 has been determined. The DNA-binding properties of the complexes were investigated by absorption titration, luminescence spectroscopy and viscosity measurements. The experimental results suggest that all these complexes bind to DNA in an intercalation mode. The results also show that the order of DNA-binding affinities (A) of this series of complexes is A(1) < A(2) < A(3). It is further confirmed that a ligand planarity of the complexes is a very important factor in affecting the DNA-binding behaviors of such complexes. Theoretical studies for these complexes were also carried out with the density functional theory (DFT) method. The trend in the DNA-binding affinities of this series of complexes can be reasonably explained by the synthetical considerations of the calculated planarity of intercalative ligands, some frontier molecular orbital energies of the complexes and the planarity area (S) of the intercalative ligands.  相似文献   

3.
Two new ruthenium complexes [Ru(bpy)2(mitatp)](ClO4)21 and [Ru(bpy)2(nitatp)](ClO4)22 (bpy = 2,2′-bipyridine, mitatp = 5-methoxy-isatino[1,2-b]-1,4,8,9-tetraazatriphenylene, nitatp = 5-nitro-isatino[1,2-b]-1,4,8,9-tetraazatriphenylene) have been synthesized and characterized by elemental analysis, 1H NMR, mass spectrometry and cyclic voltammetry. Spectroscopic and viscosity measurements proved that the two Ru(II) complexes intercalate DNA with larger binding constants than that of [Ru(bpy)2(dppz)]2+ (dppz = dipyrido[3,2-a:2′,3′-c]phenazine) and possess the excited lifetime of microsecond scale upon binding to DNA. Both complexes can efficiently photocleave pBR322 DNA in vitro under irradiation. Singlet oxygen (1O2) was proved to contribute to the DNA photocleavage process, the 1O2 quantum yields was determined to be 0.43 and 0.36 for 1 and 2, respectively. Moreover, a photoinduced electron transfer mechanism was also found to be involved in the DNA cleavage process.  相似文献   

4.
The P,P′diphenylmethylenediphosphinic acid (H2pcp) reacts with Co(ClO4)2 · 6H2O and 4,4′-bipyridine to give a mixture of two polymeric isomers of formula [Co(pcp)(bipy)0.5(H2O)2], {red (1) and pink (2)} and the new violet hybrid [Co(Hpcp)2] (3). The pure red and violet species have been obtained by the reaction of H2pcp with Co(CH3COO)2 · 4H2O and bipy or with Co(ClO4)2 · 6H2O, respectively. The analogous reaction of Ni(CH3COO)2 · 4H2O or Ni(ClO4)2 · 6H2O with H2pcp and bipy affords only the [Ni(pcp)(bipy)0.5(H2O)2] species (4). The two cobalt isomers present different structural arrangements. Whereas the red isomer (1) shows an undulated 2D layered structure, the pink one (2) forms an infinite monodimensional strand. Both the architectures extend to higher dimensions through hydrogen bonding interactions. The nickel derivative is isomorphous with the red cobalt isomer. The violet [Co(Hpcp)2] (3), which is isomorphous with the complexes of the reported series [M(Hpcp)2], M = Ca(II), Mg(II), presents a monodimensional polymeric structure. Compounds 1 and 4 show a very similar thermal behaviour, the two water molecules being lost in the temperature range 25-150 and 160-320 °C, respectively. Temperature dependent X-ray powder diffractometry (TDXD) has been performed on compound 1 in order to follow the structural transformations that occur during the heating process.  相似文献   

5.
Treatment of [H(TMSO)][trans-RuCl4(TMSO)2] (1) with 2,2′-bipyridine (bpy) in ethanol at room temperature resulted an unknown mer-[RuCl3(TMSO)(bpy)] (3) and a known cis-[RuCl2(TMSO)4] (4) (TMSO =  tetramethylene sulfoxide) complexes. The 3 was obtained by the substitution with bpy in mer-[RuCl3(TMSO)3] (2), whereas 4 was obtained by one-electron reduction of 2, suggesting that 2 is a precursor for both 3 and 4. The structure of 3 was determined by single crystal X-ray diffraction. The reaction is a new synthetic procedure for 3 and/or 3 and 4 in mild reaction conditions from the anionic complex 1. It involves simultaneous substitution and redox reaction. This is the first known example of precisely characterized Ru(III)-chloride-TMSO-bpy-complex derived from anionic [H(TMSO)][trans-RuCl4(TMSO)2] at room temperature.  相似文献   

6.
Two isomeric dibenzo-O2S2 macrocycles L1 and L2 have been synthesised and their coordination chemistry towards palladium(II) has been investigated. Two-step approaches via reactions of 1:1-type complexes, [cis-Cl2LPd] (1a: L = L1, 1b: L = L2), with different O2S2 macrocycle systems (L1 and L2) have led to the isolation of the following bis(O2S2 macrocycle) palladium(II) complexes in the solid state: [Pd(L1)2](ClO4)2 (2a) and a mixture of [Pd(L1)2](ClO4)2 (2a) + [Pd(L2)2](ClO4)2 (2b).  相似文献   

7.
Treatment of ‘RuCl3 · 3H2O’ with Ph2AsCH2AsPh2 (dpam) in hot EtOH gives either trans-[RuCl2(dpam-As,As′)(dpam-As)2] (1), or cis-[RuCl2(dpam-As,As′)2] (2), depending on the mole ratio. On exposure to light, solutions of 2 isomerise to trans-[RuCl2(dpam-As,As′)2] (3). Treatment of [RuCl2(PPh3)3] with two equivalents of dpam in CH2Cl2 gave a mixture of two products, from which trans-[RuCl2(PPh3) (dpam-As,As′)(dpam-As)] (4) was isolated by recrystallisation. The crystal structures of 1-4 are reported. Complexes 1-3 in CH2Cl2 undergo electrochemical oxidation to Ru(III), and the Ru(III) form of 2 undergoes isomerisation on the voltammetric timescale to the Ru(III) form of 3.  相似文献   

8.
Starting from previously reported cis-Ru(MeL)2Cl2, where MeL is 4,4,4′,4′-tetramethyl-2,2′-bisoxazoline, cis-Ru(MeL)2Br2 (1), cis-Ru(MeL)2I2 (2), cis-Ru(MeL)2(NCS)2 · H2O (3), cis-Ru(MeL)2(N3)2 (4) and cis-[Ru(MeL)2(MeCN)2](PF6)2 · (CH3)2CO (5) are synthesised. The X-ray crystal structures of complexes 1, 2, 3 and 5 have been determined. All the five new complexes have been characterized by FTIR, ESIMS and 1H NMR. In cyclic voltammetry in acetonitrile at a glassy carbon electrode, the complexes display a quasireversible Ru(II/III) couple in the range 0.32-1.71 V versus NHE. The Ru(II/III) potentials yield a satisfactorily linear correlation with Chatt’s ligand constants PL for the monodantate ligands. From the intercept and by comparing the known situation in Ru(2,2′-bipyridine)2L2, it is concluded that MeL, a non-aromatic diimine, is significantly more π-acidic than 2,2′-bipyridine.  相似文献   

9.
The reaction of Cd(OAc)2 · 4H2O and 1-alkyl-2-(arylazo)imidazole [RaaiR′ where R = H (a), Me (b); R′ = Me (1/3/5), Et (2/4/6)] and NH4NCS/NaNCO in methanol in 1:2:2 mole ratio has afforded [Cd(RaaiR′)2(NCS)2] (34) and [Cd(RaaiR′)2(NCO)2] (56) complexes. The complexes are characterized by different physicochemical methods and in one case, the structure was confirmed by single crystal X-ray diffraction study for title compounds.  相似文献   

10.
[Ru(2,2′-bipyridine)2(Hdpa)](BF4)2 · 2H2O (1), [Ru(1,10-phenanthroline)2(Hdpa)] (PF6)2 · CH2Cl2 (2) and [Ru(4,4,4′,4′-tetramethyl-2,2′- bisoxazoline)2(Hdpa)] (PF6)2 (3) are synthesized where Hdpa is 2,2′-dipyridylamine. The X-ray crystal structures of 1 and 2 have been determined. Hdpa in 1 and 2 is found to bind the metal via the two pyridyl N ends. Comparing the NMR spectra in DMSO-d6, it is concluded that 3 has a similar structure. The pKa values (for the dissociation of the NH proton in Hdpa) of free Hdpa and its complexes are determined in acetonitrile by exploiting molar conductance. These correlate linearly with the chemical shift of the NH proton in the respective entities.  相似文献   

11.
The use of succinamic acid (H2sucm) in Cu(ClO4)2·6H2O/N,N′-donor [2,2′-bipyridine (bpy), 1,10-phenanthroline (phen), 4,4′-dimethyl-2,2′-bipyridine (dmbpy), 4,4′-bipyridine (4,4′-bpy)] reaction mixtures yielded compounds [Cu2(Hsucm)3(bpy)2](ClO4)·0.5MeOH (1·0.5MeOH), [Cu2(Hsucm)(OH)(H2O)(bpy)](ClO4)2 (2), [Cu4(Hsucm)5(dmbpy)4]n(ClO4)3n·nH2O ·0.53nMeOH (3·nH2O·0.53nMeOH), [Cu2(Hsucm)2(dmbpy)2(H2O)2](ClO4)2·2H2O (4·2H2O), [Cu2(Hsucm)2(phen)2(H2O)2](ClO4)2·1.8MeOH (5·1.8MeOH), [Cu2(Hsucm)2(phen)2(MeOH)2](ClO4)2·MeOH (6·MeOH) and [Cu(Hsucm)2(H2O)(4,4′-bpy)]n (7). The succinamate(−1) ligand exists in five different coordination modes in the structures of 1-7, i.e. the common syn, syn μ2OO′ in 1-6, the μ22O in 1, the μ22OO′ in 1, the μ32O2O′ in 3, and the monodentate κO in 7. The primary amide group of Hsucm remains uncoordinated and participates in intra- and intermolecular hydrogen bonding interactions leading to interesting crystal structures. Characteristic IR bands of the complexes are discussed in terms of the known structures and the coordination modes of the Hsucm ligands. The thermal decomposition of representative complexes was monitored by TG/DTG and DTA measurements.  相似文献   

12.
We report here the synthesis, characterisation, electrochemical, photophysical and protein-binding properties of four luminescent ruthenium(II) polypyridine indole complexes [Ru(bpy)2(L1)](PF6)2 (1), [Ru(bpy)2(L2)](PF6)2 (2), [Ru(L1)3](PF6)2 (1a), and [Ru(L2)3](PF6)2 (2a) (bpy = 2,2′-bipyridine; L1 = 4-(N-(2-indol-3-ylethyl)amido)-4′-methyl-2,2′-bipyridine; L2 = 4-(N-(6-N-(2-indol-3-ylethyl)hexanamidyl)amido)-4′-methyl-2,2′-bipyridine). Their indole-free counterparts, [Ru(bpy)2(L3)](PF6)2 (3) and [Ru(L3)3](PF6)2 (3a) (L3 = 4-(N-(ethyl)amido)-4′-methyl-2,2′-bipyridine), have also been synthesised for comparison purposes. Cyclic voltammetric studies revealed ruthenium-based oxidation at ca. +1.3 V versus SCE and diimine-based reductions at ca. −1.20 to −2.28 V. The indole moieties of complexes 1, 2, 1a and 2a displayed an irreversible wave at ca. +1.1 V versus SCE. All the ruthenium(II) complexes exhibited intense and long-lived orange-red triplet metal-to-ligand charge-transfer 3MLCT (dπ(Ru) → π*(L1-L3)) luminescence upon visible-light irradiation in fluid solutions at 298 K and in alcohol glass at 77 K. The binding of the indole-containing complexes to bovine serum album (BSA) has been studied by quenching experiments and emission titrations.  相似文献   

13.
A facile synthetic procedure has been used to prepare one five-coordinate and four six-coordinate copper(II) complexes of 4′-chloro-2,2′:6′,2″-terpyridine (tpyCl) ligand with different counterions (, , , , and ) in high yields. They are formulated as [Cu(tpyCl-κ3N,N,N′′)(SO4-κO)(H2O-κO)] · 2H2O (1), trans-[Cu(tpyCl-κ3N,N,N″)(NO3-κO)2(H2O-κO)] (2), [Cu(tpyCl-κ3N,N,N″)2](BF4)2 (3), [Cu(tpyCl-κ3N,N,N″)2](PF6)2 (4) and [Cu(tpyCl-κ3N,N,N″)2](ClO4)2 (5) and versatile interactions in supramolecular level including coordinative bonding, O-H?O, O-H?Cl, C-H?F, and C-H?Cl hydrogen bonding, π-π stacking play essential roles in forming different frameworks of 1-5. It is concluded that the difference of coordination abilities of the counterions used and the experimental conditions codominate the resulting complexes with 1:1 or 1:2 ratio of metal and ligand.  相似文献   

14.
Complexes of the type (R-bpy)2RuCl2 (R: H, Me, tert-but) were synthesised by microwave-activated reactions of [Ru(cod)Cl2]n with substituted 2,2′-bipyridines in dimethylformamide as the solvent. The complexes were isolated in high yields and high purity from the reaction mixture. Microwave-assisted or thermal reaction of the (R-bpy)2RuCl2 solutions with substituted bibenzimidazoles, 1,10 phenanthroline or bipyrimidine in dmf/water mixtures resulted in the formation of mixed ligand complexes of the type [(R-bpy)2Ru(L-L)]Cl2. The complexes were characterised by NMR spectroscopy and MS. Furthermore, their photochemical and electrochemical properties were investigated and the solid state structure of (4-tert-butyl-bpy)2RuCl2 (3), [(4-tert-butyl-bpy)2Ru(tetramethylbibenzimidazole)](PF6)2 (4), and [(4-tert-butyl-bpy)2Ru(bipyrimidine] (PF6)2 (5) was determined by X-ray diffraction analysis of single crystals.  相似文献   

15.
The new complex, [RuII(bpy)2(4-HCOO-4′-pyCH2 NHCO-bpy)](PF6)2 · 3H2O (1), where 4-HCOO-4′-pyCH2NHCO-bpy is 4-(carboxylic acid)-4′-pyrid-2-ylmethylamido-2,2′-bipyridine, has been synthesised from [Ru(bpy)2(H2dcbpy)](PF6)2 (H2dcbpy is 4,4′-(dicarboxylic acid)-2,2′-bipyridine) and characterised by elemental analysis and spectroscopic methods. An X-ray crystal structure determination of the trihydrate of the [Ru(bpy)2(H2dcbpy)](PF6)2 precursor is reported, since it represented a different solvate to an existing structure. The structure shows a distorted octahedral arrangement of the ligands around the ruthenium(II) centre and is consistent with the carboxyl groups being protonated. A comparative study of the electrochemical and photophysical properties of [RuII(bpy)2(4-HCOO-4′-pyCH2NHCO-bpy)]2+ (1), [Ru(bpy)2(H2dcbpy)]2+ (2), [Ru(bpy)3]2+ (3), [Ru(bpy)2Cl2] (4) and [Ru(bpy)2Cl2]+ (5) was then undertaken to determine their variation upon changing the ligands occupying two of the six ruthenium(II) coordination sites. The ruthenium(II) complexes exhibit intense ligand centred (LC) transition bands in the UV region, and broad MLCT bands in the visible region. The ruthenium(III) complex, 5, displayed overlapping LC bands in the UV region and a LMCT band in the visible. 1, 2 and 3 were found, via cyclic voltammetry at a glassy carbon electrode, to exhibit very positive reversible formal potentials of 996, 992 and 893 mV (versus Fc/Fc+) respectively for the Ru(III)/Ru(II) half-cell reaction. As expected the reversible potential derived from oxidation of 4 (−77 mV (versus Fc/Fc+)) was in excellent agreement with that found via reduction of 5 (−84 mV (versus Fc/Fc+)). Spectroelectrochemical experiments in an optically transparent thin-layer electrochemical cell configuration allowed UV-Vis spectra of the Ru(III) redox state to be obtained for 1, 2, 3 and 4 and also confirmed that 5 was the product of oxidative bulk electrolysis of 4. These spectrochemical measurements also confirmed that the oxidation of all Ru(II) complexes and reduction of the corresponding Ru(III) complex are fully reversible in both the chemical and electrochemical senses.  相似文献   

16.
Palladium(II) and platinum(II) complexes with N-alkylpyridylpyrazole-derived ligands, 2-(1-ethyl-5-phenyl-1H-pyrazol-3-yl)pyridine (L1) and 2-(1-octyl-5-phenyl-1H-pyrazol-3-yl)pyridine (L2), cis-[MCl2(L)] (M = Pd(II), Pt(II)), have been synthesised. Treatment of [PdCl2(L)] (L = L1, L2) with excess of ligand (L1, L2), pyridine (py) or triphenylphosphine (PPh3) in the presence of AgBF4 and NaBPh4 produced the following complexes: [Pd(L)2](BPh4)2, [Pd(L)(py)2](BPh4)2 and [Pd(L)(PPh3)2](BPh4)2. All complexes have been characterised by elemental analyses, conductivity, IR and NMR spectroscopies. The crystal structures of cis-[PdCl2(L2)] (2) and cis-[PtCl2(L1)] (3) were determined by a single crystal X-ray diffraction method. In both complexes, the metal atom is coordinated by one pyrazole nitrogen, one pyridine nitrogen and two chlorine atoms in a distorted square-planar geometry. In complex 3, π-π stacking between pairs of molecules is observed.  相似文献   

17.
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   

18.
The synthesis, structure and spectral and redox properties of the copper(II) complexes [Cu(pmtpm)Cl2] (1) and [Cu(pmtpm)2](ClO4)2 (6), where pmtpm is the linear tridentate ligand 2-pyridyl-N-(2′-methylthiophenyl)methyleneimine containing a thioether and two pyridine donors, are described. Also, the mixed ligand complexes [Cu(pmtpm)(diimine)](ClO4)2 (2-5), where the diimine is 2,2′-bipyridine (bpy) (2), 1,10-phenanthroline (phen) (3), 2,9-dimethyl-1,10-phenanthroline (2,9-dmp) (4) or dipyrido-[3,2-d:2′,3′-f]-quinoxaline (dpq) (5), have been isolated and studied. The X-ray crystal structures of the complexes 1, [Cu(pmtpm)(2,9-dmp)](ClO4)24 and 6 have been successfully determined. The complex 1 possesses a trigonal bipyramidal distorted square based pyramidal (TBDSBP) coordination geometry in which three corners of the square plane are occupied by two nitrogens and thioether s of pmtpm ligand and the remaining equatorial and the axial positions by two chloride ions. The complex 4 contains a CuN4S chromophore also with a TBDSBP coordination geometry in which two nitrogens and the thioether sulfur of pmtpm ligand occupy three corners of the square plane. One of the two nitrogens of 2,9-dmp ligand is equatorially coordinated and the other axially to copper. On the other hand, the complex 6 is found to possess a square based pyramidal distorted trigonal bipyramidal (SPDTBP) coordination geometry. The CuN2S trigonal plane in it is comprised of the pyridine and imine nitrogens and the thioether sulfur of the pmtpm ligand. The pyridine nitrogens of the ligand occupy the axial positions and the second thioether sulfur remains uncoordinated. On long standing in acetonitrile solution the mixed ligand complexes 2 and 3 undergo ligand disproportionation to provide the corresponding bis-complexes of bpy and phen, respectively, and 6. The electronic and EPR spectral parameters and the positive redox potential of complex 4 are consistent with the equatorial location of the thioether sulfur in the square-based coordination geometry around copper(II). On the other hand, the higher g and lower A values and lower E1/2 values for the complexes 2, 3 and 5 are consistent with the axial coordination of the thioether sulfur. Also, the Cu(II)/Cu(I) redox potentials increase with increase in number of aromatic rings of the diimine ligand. The steric and electronic effects of the bidentate diimine ligands in orienting the thioether coordination to axial or equatorial position are discussed.  相似文献   

19.
The reactions of 4-(p-dimethylaminophenyl)-6-phenyl-2,2′-bipyridine (HL) with three metal salts of platinum(II), copper(I) and zinc(II) provide the new complexes [Pt(L)(PPh3)]ClO4 (1), [Cu(HL)2]BF4 (2), [Cu(HL)(PPh3)]BF4 (3) and [Zn(HL)2](ClO4)2 (4). All the structures of these four complexes have been characterized by single crystal X-ray diffraction, and their spectroscopic properties were investigated. Especially for complex 1, upon protonation, the excited state can be tuned from the intraligand charge transfer (ILCT) to the metal-to-ligand charge transfer (MLCT), and such switching in the excited state is acid/base reversible. The time-dependent density functional theory (TD-DFT) calculation was used to interpret the absorption spectra of complex 1, and the calculated result is consistent with those of experiments results. In contrast with 1, the lowest energy absorption at 410-650 nm of complexes 2 and 3 can be assigned to MLCT excited state. In solid state or solution complex 4 exhibits intense photoluminescence attributed to a ILCT transition in nature.  相似文献   

20.
The dinuclear complex [Cu2(dpbp)2(NCMe)4][BF4]2 (1) has been prepared by treating [Cu(NCMe)4][BF4] with 4,4′-bis(diphenylphosphino)biphenylene (abbreviated as dpbp). Reactions of 1 with 2,2′-bipyridine and 1,1′-bis(diphenylphosphino)ferrocene (abbreviated as dppf) afford [Cu2(dpbp)2(2,2′-bipy)2][BF4]2 (2) and [Cu2(dpbp)(dppf)2][BF4]2 (3), respectively. In contrast, compound 1 reacts with tetra(2-pyridyl)ethyl-1,4-diaminobutane (abbreviated as tpyda) to produce the polymeric complex {[Cu2(dpbp)(tpyda)][BF4]2}n (4). Compounds 1-4 are photoluminescent with the emission band (λmax) in the range 510-554 nm. The crystal structures of 1 and 4 have been determined by an X-ray diffraction study.  相似文献   

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