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1.
Complexing processes in MII-N-diisopropoxythiophosphorylthiobenzamide binary systems (M = Co, Ni, Cu) in metal(II) hexacyanoferrate(II) gelatin-immobilized matrices upon contact with aqueous–alkaline (pH = 12.0 ± 0.1) solutions of organic compounds have been studied. It has been shown that, in CoII and CuII, the initial act of complexing involves destruction of the CoII and CuII hexacyanoferrates(II) by OH ions, leading to formation of the corresponding hydroxides which react with the ligand indicated. In the both systems, successive addition of two ligand molecules per M(OH)2 fragment occurs and [MB(OH)(OH2)] and [MB2] coordination compounds are formed (B-a singly deprotonated ligand form). In the NiII-N-diisopropoxythiophosphorylthiobenzamide system, the formation of three complexes, (Ni2BOH)2[Fe(CN)6], [NiB(OH)(OH2)] and [NiB2] occurs.  相似文献   

2.
In the title compound, [Ni(N3)2(C6H6N2O)2], the NiII atom lies on an inversion centre. The distorted octahedral nickel(II) coordination environment contains two planar trans-related N,O-chelating picolinamide ligands in one plane and two monodentate azide ligands perpendicular to this plane. Molecules are linked into a three-dimensional framework by N—H...N hydrogen bonds.  相似文献   

3.
Potentially tetradentate ligands N,N"-di(2-hydroxybenzyl)ethylenediamine (L1) and N,N"-di(2-hydroxybenzyl)o-phenylenediamine (L2) and complexes of Cu(II), Co(II), and Ni(II) with L1and L2were synthesized. The EPR and electronic spectroscopy methods were used to reveal the octahedral structure of the Cu(II) complex with L1in the solid state. In water–alcohol solutions, the Cu(II) and Ni(II) complexes with both ligands have distorted octahedral structures. The Co(II) complexes form dioxygen adduct with L1. In the presence of oxygen, the ligands in the obtained complex compounds can undergo oxidative dehydrogenation with selective formation of the respective disalicylaldimines. In the case of L2, the oxidative dehydrogenation is observed for the complexes of all studied metals in comparatively mild conditions (T= 30°C, methanol and other solvents), while in the case of L1, it occurs only with the Co(II) complexes in the presence of pyridine.  相似文献   

4.
The compounds [Cu(N3)(NSC)(tmen)]n (1), [Cu(N3)(NCO)(tmen)]n (2) and [Cu(N3)(NCO)(tmen)]2 (3) (tmen=N,N,N′,N′-tetramethylethylenediamine) were synthesized and studied by i.r. spectroscopy. Single crystals of compounds (1) and (3) were obtained and characterized by X-ray diffraction. The structure of compound (1) consists of neutral chains of copper(II) ions bridged by a single azido ligand showing the asymmetric end-to-end coordination fashion. Each copper ion is also surrounded by the other three nitrogen atoms; two from one N,N,N′,N′-tetramethylethylenediamine and one from a terminal bonded thiocyanate group. Compound (2) decomposes slowly in acetone and the product formed [Cu(N3)(NCO)(tmen)]2 (3) crystallizes in the monoclinic system (P21). The structure of (3) consists of dimeric units in which the Cu atoms are penta-coordinated and connected by μ(1,3) bridging azido and cyanate ligands. In both cases the five coordinated atoms give rise to a slightly distorted square-based pyramid coordination geometry at each copper ion. The thermal behavior of [Cu(N3)(NSC)(tmen)]n (1) and [Cu(N3)(NCO)(tmen)]n (2) were investigated and the final decomposition products were identified by X-ray powder diagrams.  相似文献   

5.
The complexation of Cu(I) and Cu(II) by a series of 12-, 14- and 16-membered macrocyclic ligands 1–6 containing the N2S2 donor set has been studied potentiometrically, spectrophotometrically and voltammetrically. In the case of Cu(II), mononuclear complexes CuL2+ with stability constants of 1010–1015 are formed. In addition, partially hydrolyzed species Cu(L)OH+ are observed at pH > 10 for the 12-membered ligands. For Cu(I), beside the specis CuL+ with stabilities of 1012–1014, the unexpected formation of protonated species CuLH2+ was detected. In contrast to the well-known general trends in coordination chemistry, the stability of these protonated species increases relative to that of the complexes with the neutral ligand when the ring size and concomitantly the distance between neighbouring donor atoms is decreased. From the stability constants of the Cu(I)- and Cu(II)-complexes the redox potentials have been calculated and are compared to the values of E1/2 obtained by cyclic voltammetry. Despite the identical donor set the Cu(II)/Cu(I) redox potentials of the complexes are spanning a range of 340 mV or six orders of magnitude in relative stability, reflecting the importance of subtle differences in steric requirements.  相似文献   

6.
A new polymeric copper complex, viz.catena‐poly[[[μ‐N,N′‐bis(3‐amino­propyl)oxa­mid­ato‐κ6N,N′,O:N′′,N′′′,O′]­dicopper(II)]‐di‐μ‐dicyan­amido‐1:1′κ2N1:N5;2:2′κ2N1:N5], [Cu2(C8H16N4O2)(C2N3)2]n or [Cu(oxpn)0.5{N(CN)2}]n [where H2oxpn is N,N′‐bis(3‐amino­propyl)­ox­amide], has been ­synthesized by the reaction of Cu(oxpn), [Cu(ClO4)2]·6H2O and NaN3. In the crystal structure, the Cu atom is five‐coordinate and has a square‐pyrimidal (SP) configuration. In the polymer, dicyan­amide (dca) groups link CuII cations in a μ‐1,5‐bridging mode, generating novel ladders in which each step is composed of dimeric [Cu2(oxpn)]2+ cations. Abundant hydrogen bonds connect the polymer ladders into a two‐dimensional network structure.  相似文献   

7.
Schiff bases of 1,3-dicarbonyl compounds with triamines and their Fe(III), Co(III), Ni(II) and Cu(II) complexes The preparation of new hexadentate ligands obtained by the reaction of cis, cis-1,3,5-triaminocyclohexane (tach) or 1,1,1-tris (aminomethyl)ethane (tame) with an 2-ethoxymethylidene-1,3-dicarbonyl compound as well as their Fe(III), Co(III), Ni(II) and Cu(II) complexes is reported. Fe(III) and Co(III) yield neutral complexes with an octahedral N3O3-coordination sphere, Ni(II) and Cu(II) complexes with a square-planar coordination-sphere. In the later complexes one of the bidentate branches of the ligand is not deprotonated and stays uncoordinated.  相似文献   

8.
The title compound, catena‐poly­[[μ‐cyano‐1:2κ2C:N‐dicyano‐1κ2C‐bis(N,N‐di­methyl­ethyl­enedi­amine‐2κ2N,N′)­pallad­ium(II)­copper(II)]‐μ‐cyano‐1:2′κ2C:N], [CuPd(CN)4(C4H12N2)2]n, consists of infinite quasi‐linear chains with all metal positions on centers of symmetry. The paramagnetic [Cu(dmen)2]2+ cations are linked by diamagnetic [Pd(CN)4]2− anions via bridging cyano groups, which occupy trans positions in both cation and anion, giving rise to 2,2‐TT‐type chains. The coordination polyhedron of the paramagnetic Cu atom is an octahedron exhibiting typical elongation due to the Jahn–Teller effect, with two longer Cu—N([triple‐bond]C) bonds in the axial positions [2.5528 (13) Å] and four shorter Cu—Ndmen bonds (dmen is N,N‐dimethylethylenediamine) in the equatorial plane [1.9926 (11) and 2.1149 (12) Å]. The Cu—N[triple‐bond]C angle is 138.03 (12)°. Neighboring chains form weak N—H⋯NC hydrogen bonds.  相似文献   

9.
Two new salts of the cation [CuI(dmp)2]+ (dmp is 2,9‐dimeth­yl‐1,10‐phenanthroline, C14H12N2), namely bis­[bis­(2,9‐dimeth­yl‐1,10‐phenanthroline‐κ2N,N′)copper(I)] bis­(hexa­fluorophos­phate) hemi[bis­(4‐pyridylmethyl­idene)hydrazine] acetonitrile solvate, [Cu(C14H12N2)2]2(PF6)2·0.5C12H10N4·C2H3N or [Cu(dmp)2]2(PF6)2·0.5(bpmh)·CH3CN [bpmh is bis­(4‐pyridylmethyl­idene)hydrazine, C12H10N4], (I), and bis­(2,9‐dimeth­yl‐1,10‐phenanthroline‐κ2N,N′)copper(I) dicyanamide, [Cu(C14H12N2)2](C2N3) or [Cu(dmp)2][N(CN)2], (II), are reported. The Cu—N bond lengths and the distortion from idealized tetra­hedral geometry of the dmp ligands are discussed and compared with related compounds. The bpmh molecule in (I) is π–π stacked with a dmp ligand at a distance of 3.4 Å, rather than coordinated to the metal atom. The molecule lies across an inversion center in the crystal. In (II), the normally coordinated dicyanamide mol­ecule is present as an uncoordinated counter‐ion.  相似文献   

10.
Summary New coligand isomers of composition Cu{N(CN)2}2(pz)2 and Cu{pz · N(CN)2}2 (pz = pyrazole) were prepared and studied by measuring their magnetic susceptibilities up to 4.2K and by aid of their e.s.r., ligand field and i.r. spectra. The susceptibility data have been analysed with various models for the exchange-coupled copper(II) polymers. It is shown that the resultant exchange coupling is ferromagnetic for Cu{N(CN)2}2(pz)2 (J 1.1 - 1.4 cm–1) but antiferromagnetic for Cu{pz · N(CN)2}2 (J –0.4 cm–1). A polymeric chain structure is proposed for Cu{N(CN)2}2(pz)2 havingpseudo-octahedrally coordinated copper(II) and CN-bridging dicyanamide ligands. Its coligand isomer contains anionic chelate ligands, formed by nucleophilic addition between N(CN)2 and pz in the copper(II) coordination sphere, and giving with this central atom a square-planar system. Definite, but slight axial interaction takes place between these structure units.  相似文献   

11.
Two copper(I) complexes [Cu(Cin2bda)2]ClO4 (I) and [Cu(Ncin2bda)2]ClO4 (II) have been prepared by the reaction of the ligands N2,N2′-bis(3-phenylallylidene)biphenyl-2,2′-diamine (L1) and N2,N2′-bis[3-(2-nitrophenyl)allylidene]biphenyl-2,2′-diamine (L2) and copper(I) salt. These compounds were characterized by CHN analyses, 1H NMR, IR, and UV-Vis spectroscopy. The C=N stretching frequency in the copper(I) complexes shows a shift to a lower frequency relative to the free ligand due to the coordination of the nitrogen atoms. The crystal and molecular structure of II was determined by X-ray single-crystal crystallography. The coordination polyhedron about the copper(I) center in the complex is best described as a distorted tetrahedron. A quasireversible redox behavior was observed for complexes I and II. The article is published in the original.  相似文献   

12.
The crystal structures of three first‐row transition metal–pyridine–sulfate complexes, namely catena‐poly[[tetrakis(pyridine‐κN)nickel(II)]‐μ‐sulfato‐κ2O:O′], [Ni(SO4)(C5H5N)4]n, (1), di‐μ‐sulfato‐κ4O:O‐bis[tris(pyridine‐κN)copper(II)], [Cu2(SO4)2(C5H5N)6], (2), and catena‐poly[[tetrakis(pyridine‐κN)zinc(II)]‐μ‐sulfato‐κ2O:O′‐[bis(pyridine‐κN)zinc(II)]‐μ‐sulfato‐κ2O:O′], [Zn2(SO4)2(C5H5N)6]n, (3), are reported. Ni compound (1) displays a polymeric crystal structure, with infinite chains of NiII atoms adopting an octahedral N4O2 coordination environment that involves four pyridine ligands and two bridging sulfate ligands. Cu compound (2) features a dimeric molecular structure, with the CuII atoms possessing square‐pyramidal N3O2 coordination environments that contain three pyridine ligands and two bridging sulfate ligands. Zn compound (3) exhibits a polymeric crystal structure of infinite chains, with two alternating zinc coordination environments, i.e. octahedral N4O2 coordination involving four pyridine ligands and two bridging sulfate ligands, and tetrahedral N2O2 coordination containing two pyridine ligands and two bridging sulfate ligands. The observed coordination environments are consistent with those predicted by crystal field theory.  相似文献   

13.
In the new tin(IV) and copper(II) complexes, cis‐dichlorido‐trans‐dimethyl‐cis‐bis(N,N′,N′′‐tricyclohexylphosphoric triamide‐κO)tin(IV), [Sn(CH3)2Cl2(C18H36N3OP)2], (I), and trans‐diaquabis(N,N′,N′′‐tricyclohexylphosphoric triamide‐κO)copper(II) dinitrate–N,N′,N′′‐tricyclohexylphosphoric triamide (1/2), [Cu(C18H36N3OP)2(H2O)2](NO3)2·2C18H36N3OP, (II), the N,N′,N′′‐tricyclohexylphosphoric triamide (PTA) ligands exist as hydrogen‐bonded dimers via P=O...H—N interactions around the metal center. The asymmetric unit in (I) consists of one complete complex molecule located on a general position. The SnIV coordination geometry is octahedral with two cis hydrogen‐bonded PTA ligands, two cis chloride ligands and two trans methyl groups. The asymmetric unit in (II) contains one half of a [Cu(PTA)2(H2O)2]2+ dication on a special position (site symmetry for the Cu atom), one nitrate anion and one free PTA molecule, both on general positions. The complex adopts a square‐planar trans‐[CuO2O2] coordination geometry, with the CuII ion coordinated by two PTA ligands and two water molecules. Each of the noncoordinated PTA molecules is hydrogen bonded to a neighboring coordinated PTA molecule and an adjacent water molecule; the phosphoryl O atom acts as a double‐H‐atom acceptor. The P atoms in the PTA ligands of both complexes and in the noncoordinated hydrogen‐bonded molecules in (II) adopt a slightly distorted tetrahedral environment.  相似文献   

14.
(+)-Poly[thio 1-(N-sec-butyl-N-methylaminomethyl) ethylene] (I) and (-)-poly[thio 1-(N-methyl-N-(1-phenylethyl)aminomethyl) ethylene] (II) are soluble in methanol or in a 10/90 dioxane-methanol mixture in the presence of CuCl2. This salting-in effect results from interactions between macromolecules and this salt. With a large excess of salt (molar ratio > 8) a precipitate is obtained whose composition is close to a CuCl2:monomer unit ratio of unity. Ultraviolet, optical rotatory dispersion (ORD) and circular dichroism (CD) spectra in solution are described. The three extrinsic Cotton effects observed between 300 and 800 nm are assigned to charge transfer and d-d electronic transitions of Cu(II) complexed with the macromolecules. In the same solvent system, Cu(II) shows similar induced optical activity in the presence of a nonaminated homolog, (+)-poly(propylene sulfide) taken as a model of the chains of I and II. No extrinsic Cotton effects are observed in the presence of an optically active tertiary amine without the thioether sulfur atom, (+)-N-sec-butyl-N-methyl-N-(oxirane-2-ylmethyl)amine. It is concluded that Cu(II) gives rise to charge-transfer complexes with sulfur atoms, while tertiary amine groups are probably protonated in this particular medium.  相似文献   

15.
In the two isomorphous title compounds, viz. tris­[2,2′‐bi(4,5‐di­hydro‐1,3‐oxazole)‐κ2N,N′]copper(II) diperchlorate, [Cu(C6H8N2O2)3](ClO4)2, (I), and tris­[2,2′‐bi(4,5‐di­hydro‐1,3‐oxazole)‐κ2N,N′]­nickel(II) diperchlorate, [Ni(C6H8N2O2)3](ClO4)2, (II), the MII ions each have a distorted octahedral coordination geometry formed via six N atoms from three 2,2′‐bioxazoline ligands. For each ligand, the two five‐membered rings are nearly coplanar. It is noteworthy that the Jahn–Teller effect is stronger in (I) than in (II). The three‐dimensional supramolecular structures of (I) and (II) are formed via weak hydrogen‐bonding interactions between O atoms from per­chlorate anions and H atoms from 2,2′‐bioxazoline ligands.  相似文献   

16.
The binuclear copper(II) and tetranuclear diiron(III)-porphyrin-dicopper(II) complexes with the Schiff-base ligands of N,N′-bis(2-imidazolaldehyde)ethylenediimine, N,N′-bis(2-imidazolaldehyde)-p-phenyldiimine, N,N-bis(acetylpyrazine)-ethylenediimine and N,N′-bis(acetylpyrazine)-p-phenyldiimine have been prepared and characterized. The magnetic data indicated that the spin ground states and the magneic interaction between Cu(II)-Cu(II) or Fe(III)-Cu(II) are dependent on the nature of the bridging ligands. A weak antiferromagnetic interaction between Fe(III) and Cu(II) is evident from the temperature-dependent magnetic measurements. The Mössbauer spectra of iron(III) -porphyrin sites showed an asymmetric quadrupole doublet consistent with high-spin iron(III) S = 5/2.  相似文献   

17.
We have reported herein the synthesis of three new Cu(II) complexes of tri- and tetradentate Schiff base ligands containing N3 or N4 donor set along with terminal NNN or SCN ligands: [L1Cu(NCS)]ClO4 (1), [L2Cu(NCS)2] (2) and [L3Cu(NNN)]ClO4 (3) [L1 = NC5H4C(CH3)=N(CH2)3N=C(CH3)C5H4N, L2= Me2N–(CH2)3–N=C(CH3)C5H4N and L3 = NC5H4CH=N–(CH2)4–N=CHC5H4N]. The complexes have been systematically characterised by elemental, spectroscopic and electrochemical techniques. Antimicrobial activities of the Schiff base ligands and their metal complexes have been studied using the disc diffusion method on the strains of Candida tropicalis and Bacillus megaterium. Structures of all the complexes have been unequivocally established from single crystal X-ray diffraction analyses that show the monomeric units containing a five-coordinated copper center in highly distorted square pyramidal geometry with thiocyanate or azide anion coordinated as terminal ligand. The complexes 1 and 3 crystallise in monoclinic (P21/c) and 2 in triclinic (P-1) space group, respectively.  相似文献   

18.
In the crystal structure of the title compound, bis­(2‐amino­pyrimidine‐κN1)bis­[6‐meth­yl‐1,2,3‐oxathia­zin‐4(3H)‐one 2,2‐dioxide(1−)‐κ2N3,O4]copper(II), [Cu(C4H4NO4S)2(C4H5N3)2], the first mixed‐ligand complex of acesulfame, the CuII centre resides on a centre of symmetry and has an octa­hedral geometry that is distorted both by the presence of four‐membered chelate rings and by the Jahn–Teller effect. The equatorial plane is formed by the N atoms of two amino­pyrimidine (ampym) ligands and by the weakly basic carbonyl O atoms of the acesulfamate ligands, while the more basic deprotonated N atoms of these ligands are in the elongated axial positions with a strong misdirected valence. The crystal is stabilized by pyrimidine ring stacking and by inter­molecular hydrogen bonding involving the NH2 moiety of the ampym ligand and the carbon­yl O atom of the acesulfamate moiety.  相似文献   

19.
Using 2‐amino­methyl‐1H‐benz­imidazole as the ligand, a new thio­cyanate‐bridged copper(II) complex, namely bis(2‐aminomethyl‐1H‐benz­imidazole‐κ2N2,N3)­di­thio­cyanato­copper(II),[Cu(NCS)2(C8H9N3)], has been synthesized and structurally characterized. The Cu atom is five‐coordinated and exhibits a distorted square‐pyramidal geometry. The thio­cyanate ions (NCS) act as either bridging or terminal ligands. The bridging NCS ligands connect neighboring Cu atoms, constructing chains, while the terminal NCS ligands form hydrogen bonds with amine H atoms, leading to a complicated network.  相似文献   

20.
The coordination polymers catena‐poly[[[(4,4′‐bi‐1,2,4‐triazole‐κN1)bis(thiocyanato‐κN)copper(II)]‐μ‐4,4′‐bi‐1,2,4‐triazole‐κ2N1:N1′] dihydrate], {[Cu(NCS)2(C4H4N6)2]·2H2O}n, (I), and poly[tetrakis(μ‐4,4′‐bi‐1,2,4‐triazole‐κ2N1:N1′)bis(μ‐thiocyanato‐κ2N:S)tetrakis(thiocyanato‐κN)tricadmium(II)], [Cd3(NCS)6(C4H4N6)4]n, (II), exhibit chain and two‐dimensional layer structures, respectively. The differentiation of the Lewis acidic nature of CuII and CdII has an influence on the coordination modes of the triazole and thiocyanate ligands, leading to topologically different polymeric motifs. In (I), copper ions are linked by bitriazole N:N′‐bridges into zigzag chains and the tetragonal–pyramidal CuN5 environment is composed of two thiocyanate N atoms and three triazole N atoms [basal Cu—N = 1.9530 (18)–2.0390 (14) Å and apical Cu—N = 2.2637 (15) Å]. The structure of (II) contains two types of crystallographically unique CdII atoms. One type lies on an inversion center in a distorted CdN6 octahedral environment, with bitriazole ligands in the equatorial plane and terminal isothiocyanate N atoms in the axial positions. The other type lies on a general position and forms centrosymmetric binuclear [Cd2(μ‐NCS‐κ2N:S)2(NCS)2] units (tetragonal–pyramidal CdN4S coordination). N:N′‐Bridging bitriazole ligands link the Cd centers into a flat (4,4)‐network.  相似文献   

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