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1.
A series of novel octahedral nickel(II) dithiocarbamate complexes involving bidentate nitrogen-donor ligands (phen = 1,10-phenanthroline, bpy = 2,2′-bipyridine) or a tetradentate ligand (cyclam = 1,4,8,11-tetraazacycloteradecane) of the composition [Ni(BzMetdtc)(phen)2]ClO4 (1), [Ni(Pe2dtc)(phen)2]ClO4 (2), [Ni(Bzppzdtc)(phen)2]ClO4 · CHCl3 (3), [Ni(Bzppzdtc)(phen)2](SCN) (4), [Ni(BzMetdtc)(bpy)2]ClO4 · 2H2O (5), [Ni(Pe2dtc)(cyclam)]ClO4 (6), [Ni(BzMetdtc)2(cyclam)] (7), [Ni(Bz2dtc)2(cyclam)] (8) and [Ni(Bz2dtc)2(phen)] (9) (BzMetdtc = N,N-benzyl-methyldithiocarbamate(1-) anion, Pe2dtc = N,N-dipentyldithiocarbamate(1-) anion, Bz2dtc = N,N-dibenzyldithiocarbamate(1-) anion, Bzppzdtc = 4-benzylpiperazinedithiocarbamate(1-) anion), have been synthesized. Spectroscopic (electronic and infrared), magnetic moment and molar conductivity data, and thermal behaviour of the complexes are discussed. Single crystal X-ray analysis of 3 and 8 confirmed a distorted octahedral arrangement in the vicinity of the nickel atom with a N4S2 donor set. They represent the first X-ray structures of such type complexes. The catalytic influence of complexes 2, 3, 6, and 7 on graphite oxidation was studied and discussed.  相似文献   

2.
3.
A versatile neutral metalloligand [Cu(PySal)2] (1) (PySal = 3-pyridylmethylsalicylidene-imino) was exploited as a building unit to construct five complexes {Cu[Cu(PySal)2]2}(ClO4)2 (2), {Cd[Cu(PySal)2]2(H2O)2]} (NO3)2 · 2H2O · 4CH3OH (3), {Zn[μ2-Cu(PySal)2]Cl2}n · nCH3OH (4), {Hg[μ2-Cu(PySal)2]I2}n (5) and {Cd[μ2-Cu(PySal)2]Cl2}n · nCH2Cl2 (6). [Cu(PySal)2] acts as a chelating ligand in discrete complexes 2 and 3 with unbound anions, but as a bis-monodentate bridging ligand in polymers 4, 5 and 6 when halogen anions coordinated cooperatively to metal cations. The coordination geometry of Cu2+ is well-defined square planar in bridging [Cu(PySal)2], analogous to that in free metalloligand (1), but it is distorted square planar in chelating [Cu(PySal)2].  相似文献   

4.
Syntheses of complexes of the type [ML(NO3)2], where M = Co(II), Ni(II), and Cu(II), L = N-(2-pyridylethyl)pyridine-2-carbaldimine, a tridentate ligand, are described. They were characterized by elemental analysis, spectral, magnetic, thermal studies, and X-ray crystallography. In the cobalt (1), nickel (2), and copper (3) complexes, the bivalent metal ion is coordinated by the three nitrogen atoms of the tridentate L with two pyridine-N groups occupying trans positions. Amongst the two nitrates one coordinates in a bidentate fashion while the other adopts a monodentate fashion. The X-band EPR spectra of 1, 2, and 3 in the polycrystalline state and in acetonitrile solution at 77 K are reported. Room temperature vibrating sample magnetometer data of 1, 2, and 3 afforded μeff values respectively of 3.928, 3.897, and 1.952 BM. The thermal stability order is 1 > 2 > 3, showing a reverse Irving-Williams trend.  相似文献   

5.
New ligand 2-(4′-biphenyl)imidazo[4,5-f][1,10]phenanthroline (BPIP) and its complexes [Ru(bpy)2(BPIP)]2+ (1) (bpy = 2,2′-bipyridine) and [Ru(phen)2(BPIP)]2+ (2) (phen = 1,10-phenanthroline) have been synthesized and characterized by mass spectroscopy, 1H NMR and cyclic voltammetry. The interaction of two Ru(II) complexes with calf thymus DNA (CT-DNA) was investigated by spectroscopic and viscosity measurements. Results indicate that both complexes bind to DNA via an intercalative mode and the DNA-binding affinity of complex 2 is much greater than that of complex 1. Furthermore, when irradiated at 365 nm, both complexes have also been found to promote the photocleavage of plasmid pBR 322 DNA.  相似文献   

6.
Treatment of the bulky iminophosphine ligand [Ph2PCH2C(Ph)N(2,6-Me2C6H3)] (L) with [M(CH3CN)2(ligand)]+n, where for M = Pd(II): ligand = η3-allyl, n = 1, and for M = Rh(I), ligand: 2(C2H4), 2(CO) or cod, n = 0, yields the mono-cationic iminophosphine complexes [Pd(η3-C3H5)(L)][BF4] (1), [Rh(cod)(L)][BF4] (2), [Rh(CO)(CH3CN)(L)][BF4] (3), and cis-[Rh(L)2][BF4] (4). All the new complexes have been characterised by NMR spectroscopy and X-ray diffraction. Complex 1 shows moderate activity in the copolymerisation of CO and ethene but is inactive towards Heck coupling of 4-bromoacetophenone and n-butyl acrylate.  相似文献   

7.
Two hetero-binuclear complexes [CpCoS2C2(B9H10)][Rh(COD)] (2a) and [CpCoSe2C2(B10H10)][Rh(COD)] (2b) [Cp = η5-pentamethylcyclopentadienyl, COD = cyclo-octa-1,5-diene (C8H12)] were synthesized by the reactions of half-sandwich complexes [CpCoE2C2(B10H10)] [E = S (1a), Se (1b)] with low valent transition metal complexes [Rh(COD)(OEt)]2 and [Rh(COD)(OMe)]2. Although the reaction conditions are the same, the structures of two products for dithiolato carborane and diselenolato carborane are different. The cage of the carborane in 2a was opened; However, the carborane cage in 2b was intact. Complexes 2a and 2b have been fully characterized by 1H, 11B NMR and IR spectroscopy, as well as by elemental analyses. The molecular structures of 2a and 2b have been determined by single-crystal X-ray diffraction analyses and strong metal-metal interactions between cobalt and rhodium atoms (2.6260 Å (2a) and 2.7057 Å (2b)) are existent.  相似文献   

8.
The new mixed Sb2O-donor ligands O{(CH2)2SbR2}2 (R = Ph, 1; R = Me, 2) with flexible backbones have been prepared in good yields as air-sensitive oils from reaction of NaSbR2 with 0.5 mol equivalents of O(CH2CH2Br)2 in thf solution. The As2O-donor analogues, O{(CH2)2AsR2}2 (R = Ph, 3; R = Me, 4) were obtained similarly from LiAsPh2 or NaAsMe2, respectively and O(CH2CH2Br)2, although ligand 4 appears to be considerably less stable with respect to C-O bond fission under some conditions than the other ligands. Using O(CH2CH2Cl)2 leads only to partial substitution by the SbPh2 or AsPh2 nucleophile. These ligands behave as bidentate chelating Sb2- or As2-donors in the distorted tetrahedral [M(L-L)2]BF4 (M = Cu or Ag; L-L = 1-4) on the basis of solution 1H and 63Cu NMR spectroscopic studies, mass spectrometry and microanalyses. Crystal structures of three representative examples with Cu(I) and Ag(I) confirm the distorted tetrahedral Sb4 or As4 coordination at the metal and allow comparisons of geometric parameters. The crystallographic identification of an unexpected Cu(I)-Cu(I) complex, [Cu2{Me2As(CH2)2OH}3](BF4)2, obtained as a by-product via C-O bond fission within ligand 4 is also reported. The distorted octahedral [RhCl2(L-L)2]Cl and the distorted square planar cis-[PtCl2(L-L)] (L-L = 1 or 2) are also described. The ether O atoms are not involved in coordination to the metal ion in any of the late transition metal complexes isolated.  相似文献   

9.
Synthesis and structural characterization of distorted pentagonal bipyramidal Co(II), pseudo-octahedral Ni(II) and Cu(II) complexes of the type [ML(NO3)2], {L = N-(2-pyridylethyl)pyridine-2-methylketimine} are reported. Characterization includes elemental analysis, spectral, magnetism, and X-ray crystallographic studies. In case of cobalt (1) both the nitrates coordinate in bidentate fashion resulting overall distorted pentagonal bipyramidal geometry. In nickel (2) and copper (3) complexes, bivalent metal ion is coordinated by the three nitrogen atoms of the tridentate L with two pyridine-N occupying trans positions and amongst the two nitrates one coordinates in a bidentate fashion while other adopts a monodentate fashion. All the complexes exhibit d–d transitions in the visible region. Complex 1 is high-spin in nature and the X-band EPR spectra of 1, and 3 at room temperature and 77 K are reported.  相似文献   

10.
Five new copper(II) complexes [Cu(dbsf)(H2O)]n · 0.5n(i-C3H7OH) (1), [Cu(dbsf)(4,4′-bpy)0.5]n · nH2O (2), [Cu(dbsf)(2,2′-bpy)(H2O)]2 · (n-C3H7OH) · 0.5H2O (3), [Cu(dbsf)(phen)(H2O)]2 · 1.5H2O (4) and [Cu(dbsf)(2,2′-bpy)(H2O)]n · n(i-C3H7OH) (5) (H2dbsf = 4,4′-dicarboxybiphenyl sulfone, 4,4′-bpy = 4,4′-bipyridine, 2,2′-bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline, i-C3H7OH = isopropanol, n-C3H7OH = n-propanol) have been synthesized under hydro/solvothermal conditions. All of the complexes are assembled from V-shaped building blocks, [Cu(dbsf)]. Complex 1 is composed of 1D double-chains. In complex 2, dbsf2− ligands and 4,4′-bpy ligands connect Cu(II) ions into catenane-like 2D layers. These catenane-like 2D layers stack in an ABAB fashion to form a 3D supramolecular network. Complexes 3 and 4 are 0D dimers, in which two [Cu(dbsf)] units encircle to form dimetal macrocyclic molecules. However, in complex 5, the V-shaped building blocks [Cu(dbsf)] are joined head-to-tail, resulting in the formation of infinite tooth-like chains. The different structures of complexes 3 and 5 may be attributed to the different solvent molecules included.  相似文献   

11.
Reactions of Mo(II)-tetraphosphine complex [MoCl24-P4)] (2; P4 = meso-o-C6H4(PPhCH2CH2PPh2)2) with a series of small molecules have been investigated. Thus, treatment of 2 with alkynes RCCR′ (R = Ph, R′ = H; R = p-tolyl, R′ = H; R = Me, R′ = Ph) in benzene or toluene gave neutral mono(alkyne) complexes [MoCl2(RCCR′)(κ3-P4)] containing tridentate P4 ligand, which were converted to cationic complexes [MoCl(RCCR′)(κ4-P4)]Cl having tetradentate P4 ligand upon dissolution into CDCl3 or CD2Cl2. The latter complexes were available directly from the reactions of 2 with the alkynes in CH2Cl2. On the other hand, treatment of 2 with 1 equiv. of XyNC (Xy = 2,6-Me2C6H3) afforded a seven-coordinate mono(isocyanide) complex [MoCl2(XyNC)(κ4-P4)] (7), which reacted further with XyNC to give a cationic bis(isocyanide) complex [MoCl(XyNC)24-P4)]Cl (8). From the reaction of 2 with CO, a mono(carbonyl) complex [MoCl2(CO)(κ4-P4)] (9) was obtained as a sole isolable product. Reaction of 9 with XyNC afforded [MoCl(CO)(XyNC)(κ4-P4)]Cl (10a) having a pentagonal-bipyramidal geometry with axial CO and XyNC ligands, whereas that of 7 with CO resulted in the formation of a mixture of 10a and its isomer 10b containing axial CO and Cl ligands. Structures of 7 and 9 as well as [MoCl(XyNC)24-P4)][PF6](8′) and [MoCl(CO)(XyNC)(κ4-P4)][PF6] (10a′) derived by the anion metathesis from 8 and 10a, respectively, were determined in detail by the X-ray crystallography.  相似文献   

12.
The reactions of N-(aryl)pyridine-2-aldimines (L-R; R = OCH3, CH3, H, Cl and NO2), derived from pyridine-2-aldehyde and para-substituted anilines, with CuI in methanol under ambient conditions afford a series of brown complexes of the type [{Cu(L-R)I}2]. The structure of the [{Cu(L-OCH3)I}2] complex has been determined by X-ray crystallography. In these dimeric complexes the two copper centers are linked through an iodo-bridge, and the L-R ligands are coordinated to the metal center through the pyridine-nitrogen and imine-nitrogen. All the complexes show characteristic 1H NMR signals and intense MLCT transitions in the visible region. These complexes also show an emission near 465 nm, whilst they are excited at 340 nm, with relatively poor quantum yields (φ ∼0.002 at 298 K). Cyclic voltammetry on all the complexes shows two successive Cu(I)-Cu(II) oxidations on the positive side of SCE, and a reduction of the coordinated imine ligand on the negative side. These copper(I) complexes are found to efficiently catalyze Suzuki type C-C coupling reactions.  相似文献   

13.
A gallium dichloro complex (L)GaIIICl2 (1) with an α-diimine ligand [(2,6-iPr2C6H3)NC(Me)]2 (L0 represents the neutral ligand, L is the radical-anionic form of the ligand, and L represents its dianion L2−) was used to synthesize a series of alkali metal complexes of an N-heterocyclic carbenes (NHCs)-like gallium(I) species. Reduction of the precursor 1 with three equivalents of Na, Li, K or KC8, respectively, in THF gave the complexes [LGaINa(THF)3] (2), [LGaILi(THF)3] (3), [LGaI2-K(THF)4}GaIL][K(THF)6] (4) and [LGaI2-K){μ2-K(THF)2}GaIL] (5). In these complexes, the original radical-anionic ligand was further reduced to the dianion, whereas the GaIII ion was reduced to GaI to yield the NHCs analogue [:GaN2C2], which then coordinated to alkali metal ions to form the complexes 2-5. Single crystal X-ray diffraction analyses revealed that these complexes feature direct Ga-M bonds (M = Li, Na, and K), which have also been studied by DFT computations.  相似文献   

14.
A Mo(0) complex containing a new tetraphosphine ligand [Mo(P4)(dppe)] (1; P4 = meso-o-C6H4(PPhCH2CH2PPh2)2, dppe = Ph2PCH2CH2PPh2) reacted with CO2 (1 atm) at 60 °C in benzene to give a Mo(0) carbonyl complex fac-[Mo(CO)(η3-P4O)(dppe)] (2), where the O abstraction from CO2 by one terminal P atom in P4 takes place to give the dangling P(O)Ph2 moiety together with the coordinated CO. On the other hand, reaction of 1 with TolNCS (Tol = m-MeC6H4) in benzene at 60 °C resulted in the incorporation of three TolNCS molecules to the Mo center, forming a Mo(0) isocyanide-isothiocyanate complex trans,mer-[Mo(TolNC)22-TolNCS)(η3-P4S)] (4), where the S abstraction occurs from two TolNCS molecules by P4 and dppe to give the η3-P4S ligand and free dppeS, respectively, together with two coordinated TolNC molecules. The remaining site of the Mo center is occupied by the third TolNCS ligating at the CS bond in an η2-manner. The X-ray analysis has been undertaken to determine the detailed structures for 2 and 4.  相似文献   

15.
A series of Cu(I) and Cu(II) complexes containing substituted ketiminate ligands was synthesized. Reaction of CuCl2 with 2 equiv. of Li[OC(Me)CHC(Me)N(Ar)] in toluene generated dark green solid of Cu[OC(Me)CHC(Me)N(Ar)]2 (1). Similarly, Cu(I) complex, {Cu[OC(Me)CHC(Me)N(Ar)]Li[OC(Me)CHC(Me)N(Ar)]}2 (2) was synthesized by reacting 2 equiv. of Li[OC(Me)CHC(Me)N(Ar)] with CuCl in toluene at room temperature for 12 h. While the reaction of CuCl with Li[OC(Me)CHC(Me)N(Ar)] in the presence of triphenylphosphine in THF solution at room temperature, a three-coordinated Cu[OC(Me)CHC(Me)N(Ar)](PPh3) (3) can be isolated in high yield. Replacing the PPh3 of 3 with N-heterocarbene (NHC) generates Cu[OC(Me)CHC(Me)N(Ar)](NHC) (4) in low yield. Complexes 2, 3, and 4 were characterized by 1H and 13C NMR spectroscopies and all molecules were structurally characterized by X-ray diffractometry. Two coordination modes of ketiminate ligands were found in the molecular structure of 2, one of which is copper-coordinated terminal ketiminates and the other is lithium-copper-coordinated bridging ketiminates.  相似文献   

16.
The complexes [W(CO)5(Ph2SbX)], X = Cl (1), Br (2) and I (3) were prepared by reaction of [W(CO)5(tetrahydrofuran)] with Ph2SbX. The structures of 1-3 were studied by X-ray diffraction. In the crystals there are weak contacts between the oxygen atoms of the CO ligands and antimony atoms of neighbouring molecules. DFT calculations were carried out for 1 using gradient corrected functional B3LYP. The bonding between Ph2SbCl and the W(CO)5 fragment in 1 was analysed using charge decomposition analysis.  相似文献   

17.
Three novel 1D Cu(I) coordination polymers [Cu4X4(pprd)2]n (X = Cl(1), Br(2) and I(3); pprd = 4-(2-pyridyl)pyrimidine) were systematically synthesized by Cu(I) halides and the pprd ligand, and they have been characterized by X-ray, IR, and TG-DTA analyses. The molecular structure of complex 1 essentially resembles to that of complex 2. In complexes 1 and 2, four Cu(I) atoms are bridged by four Cl or Br anions to form an eight-membered Cu4X4 framework in the twist-chair form. Furthermore, the Cu4X4 frameworks are coordinated by the chelate and bridging sites of two pprd ligands to form a unique 1D two-stepped Cu(I) coordination polymer, in which two stairs are formed by the Cu4X4 core and two heteroaromatic planes of pprd. In the crystal packing structures, it is interesting that two heteroaromatic planes of pprd are stacking along the b-axis for complex 1 and the a-axis for complex 2. In contrast, four Cu(I) atoms in complex 3 are bridged by four I atoms to form a Cu4I4 stepped cubane tetramer. Additionally, the Cu4I4 stepped cubane cores are linked by the chelate and bridging sites of two pprd ligands to form an infinite 1D zigzag-chain Cu(I) coordination polymer. The thermal decomposition behaviors for Cu(I)–X/pprd complexes 1, 2 and 3 were determined by thermogravimetric analysis (TG-DTA). Although the thermal decomposition behaviors of complex 1 were unidentified, those of complexes 2 and 3 were assigned. The mass loss at the first stage of thermal decomposition for polymeric [Cu4X4(pprd)2]n was identical to the formation of oligomeric [Cu4X4(pprd)] by the elimination of one pprd molecule. The mass loss at the next stage was decided to the formation of Cu4X4 by the elimination of another pprd molecule.  相似文献   

18.
The preparation, crystal structure and magnetic properties of a new oxalate-containing copper(II) chain of formula {[(CH3)4N]2[Cu(C2O4)2] · H2O}n (1) [(CH3)4N+ = tetramethylammonium cation] are reported. The structure of 1 consists of anionic oxalate-bridged copper(II) chains, tetramethylammoniun cations and crystallization water molecules. Each copper(II) ion in 1 is surrounded by three oxalate ligands, one being bidentate and the other two exhibiting bis-bidenate coordination modes. Although all the tris-chelated copper(II) units from a given chain exhibit the same helicity, adjacent chains have opposite helicities and then an achiral structure results. Variable-temperature magnetic susceptibility measurements of 1 show the occurrence of a weak ferromagnetic interaction through the oxalate bridge [J = +1.14(1) cm−1, the Hamiltonian being defined as H = –JnmSi · Sj]. This value is analyzed and discussed in the light of available magneto-structural data for oxalate-bridged copper(II) complexes with the same out-of-plane exchange pathway.  相似文献   

19.
We report a combined experimental and computational study of new rhenium tricarbonyl complexes based on the bidentate heterocyclic N-N ligands 2-(4-methylpyridin-2-yl)benzo[d]-X-azole (X = N-CH3, O, or S) and 2-(benzo[d]-X-azol-2-yl)-4-methylquinoline (X = N-CH3, O, or S). Two sets of complexes are reported. Chloro complexes, described by the general formula Re(CO)3[2-(4-methylpyridin-2-yl)benzo[d]-X-azole]Cl (X = N-CH3, 1; X = O, 2; X = S, 3) and Re(CO)3[2-(benzo[d]-X-azol-2-yl)-4-methylquinoline]Cl (X = N-CH3, 4; X = O, 5; X = S, 6) were synthesized heating at reflux Re(CO)5Cl with the appropriate N-N ligand in toluene. The corresponding pyridine set {Re(CO)3[2-(4-methylpyridin-2-yl)benzo-X-azole]py}PF6 (X = N-CH3, 7; X = O, 8; X = S, 9) and {Re(CO)3[2-(benzo[d]-X-azol-2-yl)-4-methylquinoline]py}PF6 (X = N-CH3, 10; X = O, 11; X = S, 12) was synthesized by halide abstraction with silver nitrate of 1-6 followed by heating in pyridine and isolated as their hexafluorophosphate salts. All complexes have been fully characterized by IR, NMR, electrochemical techniques and luminescence. The crystal structures of 1 and 7 were obtained by X-ray diffraction. DFT and time-dependent (TD) DFT calculations were carried out for investigating the effect of the organic ligand on the optical properties and electronic structure of the reported complexes.  相似文献   

20.
Four copper(I) cyanide coordination polymers containing 2-(n-pyridyl)benzimidazole ligands, namely [Cu2(CN)(2-PyBIm)]n (1), [Cu2(CN)2(3-PyHBIm)]n (2), {[Cu3(CN)3(4-PyHBIm)4] · 2H2O}n (3) and [Cu5(CN)3(4-PyBIm)2]n (4), have been synthesized and characterized by X-ray crystallography. Complex 1 is a one-dimension coordination polymer in which 2-(2-pyridyl)benzimidazole is deprotonated and adopts a bridging tridentate coordination mode. Complex 2 has ladder-like structure in which 2-(3-pyridyl)benzimidazole does not deprotonate and acts as a bidentate bridge. Complex 3 displays a saddle-shaped helical chain constructed through μ2-cyanide group and the outstretched neutral 2-(4-pyridyl)benzimidazole monodentate ligand. Complex 4 shows two-dimension layer polymeric structure in which deprotonated 2-(4-pyridyl)benzimidazole acts as a tridentate bridging ligand. The cyanide groups in four complexes all act as bidentate bridging ligands. These complexes are thermal stable and display luminescence in the solid states.  相似文献   

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