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1.
Alkylation of ethylenediamine with allyl bromide in the presence of NaHCO3 in benzene-ethanol and acetone-ethanol gave N,N,N′,N′-tetraallylethylenediamine L4 and N,N,N,N′,N′-pentaallylethylenediaminium bromide (L5(H+)Br2), respectively. The ac electrochemical synthesis at copper wire electrodes in solutions of copper(II) halide and an appropriate ligand yielded single crystals of Cu(I) complexes with ethylenediaminium ([L0(H+)2]0.5CuCl2 (I) and [L0(H+)2]0.5CuBr1.67Cl0.33 (II)) and its N-allyl derivatives N,N,N′,N′-tetraallylethylenediaminium ([{L4(H+)2}0.5Cu2Cl3] (III)) and N,N,N,N′,N′-pentaallylethylenediaminium ([L5(H+)Cu4Br6] (IV)). The crystal structures of complexes I–IV were determined by X-ray diffraction. The isostructural crystals of complexes I and II are triclinic, space group P $ \bar 1 $ , Z = 2. For I: a = 5.936(3), b = 6.387(3), c = 7.126(4) Å, α = 67.82(4)°, β = 72.98(4)°, γ = 67.55(4)°, V = 227.7(2) Å3. For II a = 6.110(3), b = 6.657(3), c = 7.309(3) Å, α = 68.40(3)°, β = 72.38(3)°, γ = 67.23(3)°, V = 250.4(2) Å3. In structures I and II, the organic cations are between infinite anionic chains (Cu 2 ? ) n . The crystals of π-complex III are triclinic, space group P $ \bar 1 $ , a = 6.851(4), b = 8.729(4), c = 9.960(4) Å, α = 98.25(3)°, β = 102.29(3)°, γ = 107.30(3)°, V = 541.8(5) Å3, Z = 2. In structure III, all the four allyl groups are π-coordinated by the metal atoms of four discrete anions Cu4Cl 6 2? . The crystals of π-complex IV are monoclinic, space group C2/c, a = 15.228(5), b = 17.095(6), c = 20.182(6) Å, β = 92.43(4)°, V = 5249(3) Å3, Z = 8. Only two of five allyl groups at the same N atom are coordinated by copper(I) atoms. Structure IV contains a complex inorganic fragment of the formula (Cu4Br 6 2? ) n .  相似文献   

2.
The Eschweiler-Clarke reaction of ethylenediamine with formaldehyde and formic acid yielded N,N,N′,N′-tetramethylethylenediamine, which was alkylated with allyl chloride or allyl bromide to give the corresponding N,N′-diallyl-N,N,N′,N′-tetramethylethylenediaminium (L2+) dihalides. In methanolic solutions of copper(II) halide and an appropriate ligand, ac electrochemical synthesis with copper wire electrodes afforded single crystals of Cu(I) complexes with L2+: [L0.5CuCl2] (I), [L0.5CuCl0.72Br1.28] (II), and [L0.5CuBr2] (III). The crystal structures of complexes I–III were determined by X-ray diffraction study. The isostructural crystals of I and II are monoclinic, space group P21/n, Z = 4. For I: a = 7.632(4) Å, b = 11.318(5) Å, c = 10.635(5) Å, β = 98.551(7)°, V = 908.4(7) Å3. For II: a = 7.7415(7) Å, b = 11.4652(9) Å, c = 10.7267(10) Å, β = 98.351(4)°, V = 942.0(2) Å3. The organic cation L2+ acts as a bridge linking a pair of separate cuprous halide fragments Cu2X4. Although being isostoichiometric with I and II, complex III has a different structure. The crystals of III are monoclinic, space group P21/c, a = 6.519(2) Å, b = 9.060(3) Å, c = 16.284(6) Å, β = 97.219(4)°, V = 954.2(6) Å3, Z = 4. In structure III, the inorganic fragment forms infinite polymer chains (CuBr 2 ? ) n . The organic and inorganic parts are held together only by electrostatic interactions. Structures I–III are stabilized by hydrogen bonds (C)H…X (2.6–2.9 Å).  相似文献   

3.
The binary group 15 polyazides As(N(3))(3), Sb(N(3))(3), and Bi(N(3))(3) were stabilized by either anion or donor-acceptor adduct formation. Crystal structures are reported for [Bi(N(3))(4)](-), [Bi(N(3))(5)](2-), [bipy·Bi(N(3))(5)](2-), [Bi(N(3))(6)](3-), bipy·As(N(3))(3), bipy·Sb(N(3))(3), and [(bipy)(2)·Bi(N(3))(3)](2). The lone valence electron pair on the central atom of these pnictogen(+III) compounds can be either sterically active or inactive. The [Bi(N(3))(5)](2-) anion possesses a sterically active lone pair and a monomeric pseudo-octahedral structure with a coordination number of 6, whereas its 2,2'-bipyridine adduct exhibits a pseudo-monocapped trigonal prismatic structure with CN 7 and a sterically inactive lone pair. Because of the high oxidizing power of Bi(+V), reactions aimed at Bi(N(3))(5) and [Bi(N(3))(6)](-) resulted in the reduction to bismuth(+III) compounds by [N(3)](-). The powder X-ray diffraction pattern of Bi(N(3))(3) was recorded at 298 K and is distinct from that calculated for Sb(N(3))(3) from its single-crystal data at 223 K. The [(bipy)(2)·Bi(N(3))(3)](2) adduct is dimeric and derived from two BiN(8) square antiprisms sharing an edge consisting of two μ(1,1)-bridging N(3) ligands and with bismuth having CN 8 and a sterically inactive lone pair. The novel bipy·As(N(3))(3) and bipy·Sb(N(3))(3) adducts are monomeric and isostructural and contain a sterically active lone pair on their central atom and a CN of 6. A systematic quantum chemical analysis of the structures of these polyazides suggests that the M06-2X density functional is well suited for the prediction of the steric activity of lone pairs in main-group chemistry. Furthermore, it was found that the solid-state structures can strongly differ from those of the free gas-phase species or those in solutions and that lone pairs that are sterically inactive in a chemical surrounding can become activated in the free isolated species.  相似文献   

4.
The trans-bis(saccharinato)nickel(II) complexes with 2-aminomethylpyridine (ampy) and 2-aminoethylpyridine (aepy) have been prepared and characterized by elemental analyses, i.r., u.v.–vis., magnetic measurements and single crystal X-ray diffraction. Both structures consist of discrete molecules of the title complexes, in which the nickel(II) ion lies on an inversion centre and is octahedrally coordinated by two bidentate (N,N) ampy or aepy ligands and two anionic sac ligands, occupying trans positions. The most interesting feature of the complexes is the coordination of sac. In [Ni(sac)2(ampy)2], sac is N-bonded, whereas it is O-coordinated in [Ni(sac)2(aepy)2]. The i.r. spectra and thermal behaviour of both complexes are discussed in detail.  相似文献   

5.
The highly insoluble organic-inorganic hybrid ionic compounds N,N??-methylenedipyridinium tetrachloroplatinate(II) [(C5H5N)2CH2] · [PtCl4] and N,N??-methylenedipyridinium hexachloroplatinate(IV) [(C5H5N)2CH2] · [PtCl6] were obtained by the treatment of N,N??-methylenedipyridinium dichloride monohydrate [(C5H5N)2CH2]Cl2 · H2O with K2[PtCl4] or (NH4)2[PtCl6], respectively, in an aqueous solution. Both complexes were isolated, purified, characterised by elemental analysis, and their molecular structures were confirmed by powder X-ray diffraction. The crystal structure of both compounds consists of separated discrete dications [(C5H5N)2CH2]2+ and anions [PtCl n ]2? (n = 4 or 6). As anticipated, the dications formed a butterfly shape consisting of two pyridine rings bound to the methylene group via their N atoms, while the Pt centre had a square planar geometry in [(C5H5N)2CH2] · [PtCl4] and an octahedral coordination in [(C5H5N)2CH2] · [PtCl6]. Interestingly, both crystal structures are stabilised by intermolecular C-H??Cl non-standard hydrogen bonds, ??-?? ring interactions between two pyridine rings of adjacent dications, and also by Cl-?? interactions.  相似文献   

6.
The optically active complexes [Zn(L)2Cl2] (I) and [Zn(L1)2Cl2] (II) (L and L1 are thiosemicar-bazones of (+)-camphor and (?)-carvone, respectively) were obtained. The crystal structures of L and complex I were determined by X-ray diffraction. The structure of L consists of hydrogen-bonded molecules united into chains. The crystal structure of complex I is built from mononuclear molecules. The coordination polyhedron of the Zn atom is a distorted tetrahedron Cl2S2. The molecule L functions as a monodentate ligand. According to data from IR spectroscopy, complex II is structurally similar to complex I.  相似文献   

7.

A new dinuclear Cd(II) complex, [L2Cd2(μ-N3)2(N3)2], containing two end-on bridging azide ligands, two monodentate N3 ligands and 1,4,7-triazacyclononane as the capping ligand, has been synthesized and its structure determined by X-ray crystallography. The complex crystallizes in the monoclinic space group P21/c with a=8.467(3), b=14.359(5), c=10.115(4)Å, β=95.026(6)° and z=4. The cadmium(II) centre is six-coordinate with distorted octahedral geometry, bonded to three N atoms of the 1,4,7-triazacyclononane, two nitrogen atoms of μ-azide bridges and one nitrogen atom of a monodentate azide ligand. Neighboring Cd(II) atoms are linked by the double end-on azide bridges.  相似文献   

8.
《Journal of Coordination Chemistry》2012,65(16-18):2569-2583
Abstract

Two copper(II) coordination complexes, formulated as [Cu(tmen)(Clba)2] (1) and [Cu(tmen)(Hsal)2·H2O] (2) (where tmen?=?N,N,N′,N′-tetramethyl ethylenediamine (C6H16N2), Clba1? = 2-chlorobenzoate (C7H4ClO21?), and Hsal1? (C7H5O31? = monoanion of o-hydroxybenzoic acid (salicylic acid)), have been synthesized and characterized by elemental combustion analysis, spectroscopic techniques, thermal studies, and single crystal X-ray analyses. Complex 1 consists of two distinct monomeric units in which the coordination environment around the central copper(II) ion is a distorted octahedron with a CuN2O4 chromophore, constituted by a chelating tmen molecule, and two 2-chlorobenzoate1? anions coordinated through their carboxylate-O atoms in an asymmetrical bidentate fashion. Complex 2 is also a monomer and consists of an CuN2O3 chromophore, in which tmen is coordinated to Cu(II) through its two N atoms in a chelating bidentate fashion, and an aqua-O and the two o-hydroxybenzoate1? (HSal1?) anions are coordinated through one of their carboxylate-O atoms in a monodentate mode, forming a square pyramidal structure. Hydrogen bonding interactions especially of O–H…O, N–H…O, and C–H…Cl types interweave monomeric units and stabilize the overall crystal structures in both complexes. Thermal analysis and antibacterial activities of 1 and 2 against various bacterial strains were also investigated.  相似文献   

9.
A series of novel bischelate bridging ligands, CH3NH(CH2)2N(CH3)(CH2) n N(CH3)(CH2)2NHCH3 (n = 9, 10, 11, and 12) were synthesized as hydrochloride salts and characterized by elemental analyses, electrospray mass spectrometry, and 1H and 13C NMR spectroscopy. These ligands form [2]pseudorotaxanes with α-cyclodextrin (α-CD) and the stability constants have been determined from 1H NMR titrations in D2O. The kinetics and mechanism of the assembly and dissociation of a [2]pseudorotaxane in which α-CD has been threaded by the CH3NH2(CH2)2N(CH3)(CH2)12N(CH3)(CH2)2NH2CH 3 2+ ligand were determined in aqueous solution using 1H NMR spectroscopy. A weak inclusion of the dimethylethylenediamine end group precedes the passage of the α-CD onto the hydrophobic dodecamethylene chain.  相似文献   

10.
《Polyhedron》1999,18(8-9):1229-1234
We report the synthesis of a series of macrocyclic ligands based on N,N′,N″-1,4,7-triazacyclononane with pendant alkyne arms. N,N′,N″-tris-(3-prop-1-yne)-1,4,7-triazacyclononane (L) has three pendant alkyne arms while N-(4-but-2-yne)1,4,7-triazacyclononane (L′) and N-(5-pent-2-yne)-1,4,7-triazacyclononane (L″) each have a single pendant arm. The ligands form coordination complexes with Cu(II), Ni(II), Co(II) and Mo(0). The crystal structures of [CuL2′][PF6]2, [NiL2′][ClO4]2 and CuL″Cl2 are presented and discussed.  相似文献   

11.
ZnII and CuII complexes of the ligand edampda2– [N,N-bis(pyridylmethyl)-ethylenediamine-N,N-diacetate] have been studied in solution by 1H n.m.r. and e.p.r. spectroscopies, respectively. [ZnII(edampda)] exists in solution in a major octahedral isomer (ca. 83%) in which the two carboxylate donors and two pyridylmethyl donors remain stereochemically rigid up to 333K at pD=6.0. The major octahedral complex has equivalent glycinato and pyridyl donors as shown by equivalent AB quartets for each type of chelate. By contrast, the [ZnII(edta)]2– analogue complex is known to have processes which rapidly equilibrate the coordinated carboxylates leading to coalesced, broad singlets instead of AB quartets down to 273K (freezing point of the sample). The minor [ZnII(edampda)] species has one pendant pyridylmethyl arm. The complex does not increase in abundance up to 333K via dissociation of the major species, suggesting that it possesses a different five-coordinate geometry (approximate trigonal bipyramid). The [CuII(edampda)] complex exhibits an e.p.r. spectrum that is intermediate between rhombic or tetragonal CuII complexes (near D4h) and the reversed-e.p.r. type of trigonal bipyramidal CuII complexes (ca. D3h). The single g value of 2.079 for gg>2.03 identifies the [CuII(edampda)] complex as distorted toward trigonal bipyramidal whereas its [CuII(edtaH2)(H2O)] analogue is known to be distorted toward square pyramidal. A binuclear CuI complex of edampda2– is formed only as a transient, and it rapidly disproportionates into [CuII(edampda)] and Cu metal. A mononuclear [CuI(edampda)]– complex persists for up to 8 h, but is oxidized within 3 min by O2 to the CuII complex. [CuII(edampda)] oxidizes to CuIII with a highly irreversible wave on glassy-carbon at +1.09V compared to the [NiII/III(edampda)] wave at +1.32V.  相似文献   

12.
13.
The effect of the neutral donor ligand, L, on the Ln(2)N(2) core in the (N═N)(2-) complexes, [A(2)(L)Ln](2)(μ-η(2):η(2)-N(2)) (Ln = Sc, Y, lanthanide; A = monoanion; L = neutral ligand), is unknown since all of the crystallographically characterized examples were obtained with L = tetrahydrofuran (THF). To explore variation in L, displacement reactions between {[(Me(3)Si)(2)N](2)(THF)Y}(2)(μ-η(2):η(2)-N(2)), 1, and benzonitrile, pyridine (py), 4-dimethylaminopyridine (DMAP), triphenylphosphine oxide, and trimethylamine N-oxide were investigated. THF is displaced by all of these ligands to form {[(Me(3)Si)(2)N](2)(L)Y}(2)(μ-η(2):η(2)-N(2)) complexes (L = PhCN, 2; py, 3; DMAP, 4; Ph(3)PO, 5; Me(3)NO, 6) that were fully characterized by analytical, spectroscopic, density functional theory, and X-ray crystallographic methods. The crystal structures of the Y(2)N(2) cores in 2-5 are similar to that in 1 with N-N bond distances between 1.255(3) ? and 1.274(3) ?, but X-ray analysis of the N-N distance in 6 shows it to be shorter: 1.198(3) ?.  相似文献   

14.
The title complex, (N,N′-dimethyl-4,4′-bipyridinium)[Cd2(μ 2-Cl)4Cl2]n (1), in which the N,N′-dimethyl-4,4′-bipyridinium was generated in situ, was synthesized via hydrothermal reaction. X-Ray diffraction analysis revealed that the structure of 1 consisted of MV 2+ (MV 2+ = N,N′-dimethyl-4,4′-bipyridinium) cationic moieties and infinite [Cd2(μ 2-Cl)4Cl2]n anionic chains. The cadmium atom was bound by one terminal chlorine atom and four μ 2-bridging chlorine atoms, yielding a slightly distorted triangular bipyramid. Photoluminescent investigation revealed that the complex displayed an emission in greenish blue region.  相似文献   

15.
Chiral α,α′-diamino-meta-xylene dioximes H2L1, H2L2, and H2L3 were obtained from the naturally occurring terpenoids (+)-3-carene, (R)-(+)-limonene, and (S)-(?)-α-pinene, respectively. Reactions of these ligands with PdCl2 gave the diamagnetic complexes Pd2(H2L1)Cl4 (I), Pd2(H2L2)Cl4 (II), and Pd2(H2L3)Cl4 (III). According to X-ray diffraction data, the crystal structure of complex I consists of acentric binuclear molecules [Pd2(H2L1)Cl4]. The coordination polyhedron PdN2Cl2 is a square distorted in a tetrahedral manner (trapezium) made up of two N atoms of the tetradentate bridging cyclic ligand H2L1 and two Cl atoms. The fragments PdCl2 in the complex are cis to each other. According to the 1H NMR spectra of complexes I–III in CDCl3, the organic ligands are coordinated through the N atoms; in solution, the complexes exist in several forms.  相似文献   

16.
N,N,N??,N??-tetramethylethylenediamine is obtained by the reaction of ethylenediamine with formaldehyde and formic acid (the Eschweiler-Clarke reaction) and then alkylated with allyl chloride (or bromide) in a ratio of 1:1 or 1:2 to obtain N-allyl-N,N,N??,N??-tetramethylethylenediaminium and N,N??-diallyl-N,N,N??,N??-tetramethylethylenediaminium bromide respectively. [{C2H4N2(H+)(CH3)4(C3H5)}Cu4Cl6] (1) and [{C2H4N2(CH3)4(C3H5)2}0.5Cu2Cl1.67Br1.33] (2) ??-complexes are obtained from alcohol solutions containing an ethylenediamine derivative and copper(II) chloride by ac-electrochemical synthesis on copper wire electrodes. An XRD study of the complexes is carried out. The crystals are monoclinic; 1: P21/n space group, a = 9.0081(6) ?, b = 12.5608(7) ?, c = 16.8610(10) ?, ?? = 102.061(3)°, V = 1865.7(2) ?3, Z = 4; 2: C2/c space group, a = 14.462(2) ?, b = 12.519(1) ?, c = 12.762(2) ?, ?? = 107.861(5)°, V = 2199.1(4) ?3, Z = 8. The structure of 1 consists of infinite copper halide networks with four crystallographically independent copper atoms, one of which coordinates the double bond of the allyl group of the ligand. The [C2H4N2(H)(CH3)4(C3H5)]2+ cations are attached above and below the plane of the network. The individual fragments are bonded via an extensive system of (N)H??Cl and (C)H??Cl hydrogen bonds. The structure of 2 contains a three-dimensional copper halide framework whose cavities contain the [C2H4N2(CH3)4(C3H5)2]2+ cations that are ??-coordinated with copper(I) atoms. In both structures, the Cu(I) atom that coordinates the C=C bond has a trigonal-pyramidal coordination environment consisting of the double C=C bond of the corresponding ligand and three halogen atoms. The other Cu(I) atoms have a tetrahedral environment consisting solely of halogen atoms. The Cu-(C=C) distance is 1.958(1) ?, (1) and 1.974(1) ? (2).  相似文献   

17.
Summary The reactions of N,N,N,N-tetramethylthiuram disulfide (tmtds) with gold(III) complexes of the [Au(L)X3] type [L = N-methylimidazole (N-Melm), 2-methylbenzoxazole (2-MeBO) and 2,5-dimethylbenzoxazole (2,5-diMeBO), X = Cl, Br or I] are reported, and yielded two main types of product - [Au(Me2dtc)X2] (A) and [Au(Me2dtc)2]X (B) (Me2dtc = N,N-dimethyldithiocarbamato anion). The ratio of the product yields (B/A) depends upon the nature of the ligand (L) and halogen (X). The ratio B/A for the reaction: [Au(L)Cl3] + tmtds = A + B, increases in the sequence N-MeIm < 2- MeBO < 2,5-diMeBO, which correlates well with the level of cytotoxic activity exhibited by the [Au(L)Cl3] complexes. A and B were characterized by their i.r., u.v-vis. and 1-n.m.r. spectra. The magnetic measurements were also recorded. The data support a squareplanar geometry for gold(III) complexes with the Me2dtc ligand bonded in a bidentate fashion; a conjecture has been verified crystallographically for [Au(Me2NCS2)2]-Br·2H2O. The X-ray analysis confirmed that the complex is composed of ionic units: [Au(Me2dtc)2] + and Br and H2O molecules. The Au—S distances are markedly similar, falling in the 2.343(4)–2.350(3) A range.  相似文献   

18.
Summary Novel N2S2 macrocyclic ligands, L and L [SS-diethyl(1,3-diaminopropane) dithiocarbamate], [SS-cyclohexyl spiro-(1,3-diaminopropane) dithiocarbamate] and their complexes with MnII, FeII, CoII, NiII and CuII have been characterized by elemental analyses, conductivity measurements, i.r., u.v.-vis. and n.m.r. spectra. The divalent transition metal complexes appear to be square planar and achieve octahedral geometry when treated with bis(trimethylsilyl)-amine to yield new heterobimetallic complexes.  相似文献   

19.
Thiomethylation of para-toluidine and 4(5)-methyl-2-aminothiazoles was used to synthesize N,N′-dithol-4-yl-1,3,5-thiadiazinane and N,N′-[methylene-bis-(thiomethylene)]-bis-[4(5)-methyl-1,3-thiazole-2-amines]. A fungicidal and fungistatic effect toward some microscopic fungi, plant-disease-producing factor, was revealed for these compounds.  相似文献   

20.
Tetrathiomolybdate reacts with iron (II) in the presence of bidentate ligands to form neutral binuclear complexes [Fe(N–N)2MoS4] [N–N=2-2bipyridine(bipy) and 1,10-phenanthroline(phen)] showing intermediate spin character for FeII. The spin state of the complexes has been examined by variable temperature magnetic moment (VTM) measurements and by variable temperature Mössbauer spectroscopy. The Mössbauer spectra indicate the presence of two iron sites: one of intermediate spin and the other of low spin at room temperature. The low spin site predominates over the intermediate spin as the temperature is lowered. The structural features of the complexes are supported by i.r., Raman, electronic and FAB mass spectra and by X-ray powder diffraction data. Substitution of one bipy/phen ligand in [Fe(N–N)3]2+ by MS4 2– ligands does not impart any major effect towards the size of the redox potentials of the tris-bipy/phen complexes, although the reversible nature of their cyclic voltammetric response is affected.  相似文献   

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