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1.
Complex Formation of 5,6-Dihydroxy-7-oxa-bicyclo[2.2.1]heptane-2,3-dicarboxylic Acid with 3 d-Transition Elements Binary carboxylate complexes of bivalent 3 d-transition metal ions with 5-exo,6-cis-dihydroxy-7-oxabicyclo[2.2.1]heptane-2-exo,3-cis-dicarboxylic acid ( 2 ) have been synthesized in aqueous solution and characterized by elementary analysis, infrared and electronic spectra and magnetic susceptibility measurements. The coordination compounds have been found to undergo thermal decomposition with loss of water molecules, followed by the organic ligand to give metal oxides. The stability constants of the complexes have been determined by potentiometric measurements. It could be shown by X-ray analysis, that the dicarboxylate anion of 2 has different coordination behaviour in complexes [NiL2(H2O)3] · H2O ( 2 c ) and [CuL2(H2O)2] · 2 H2O ( 2 d ), respectively. In 2 c it acts as a tridentate chelating ligand forming together with three water molecules an only slightly distorted octahedral coordination sphere and its hydroxyl groups are coordinatively inactive. In 2 d , however, the oxygen atom of one hydroxyl group is included in coordination and by its interaction with a Cu atom of a neighboring molecule a polymeric chain structure is built up in the crystal. Two corners of the tetragonally extended coordination octahedron are occupied by water molecules. In both complexes the molecular packing is stabilized by a network of hydrogen bonds in which also the crystal water molecules are included.  相似文献   

2.
Synthesis, Crystal Structures, and Properties of Lanthanoid(III) Complexes with 7-Oxa-bicyclo[2.2.1]heptane-2,3-dicarboxylic Acid The synthesis of coordination compounds [ML(HL)(H2O)] with M = La3+, Ce3+, Pr3+, Nd3+ and H2L = 7-oxa-bicyclo[2.2.1]heptane-2-exo,3-cis-dicarboxylic acid ( 1 ) has been described. Results of IR spectroscopy and thermal decomposition are given. As a result of X-ray analyses, the four investigated lanthanoid(III) complexes are isotypic. Their stereochemistry approximates to the tri-capped trigonal prism with nine O atoms coordinating the metal atom. The bicyclic ligand acts as a tridentate chelating monoanion HL? as well as a pentadentate dianion L2? with both chelating and bridging function. One coordination place at the metal atom is occupied by a water molecule.  相似文献   

3.
Four CuII and CoII complexes–[Cu(L1)Cl2(H2O)]3/2H2O · 1/2EtOH, [Cu(L1)2Cl2]6H2O, [Co(L1)Cl2]3H2O · EtOH, and [Co2(L1)(H2O)Cl4]1.5H2O · EtOH (L1 = 2,4,6-tri(2-pyridyl)-1,3,5-triazine; TPT)–were synthesized by conventional chemical method and used to synthesize another four metal complexes–[Cu(L1)I2(H2O)]6H2O, [Cu(L1)2I2]6H2O, [Co(L1)I(H2O)2]I · 2H2O, and [Co2(L1)I4(H2O)3]–using tribochemical reaction, by grinding it with KI. Substitution of chloride by iodide occurred, but no reduction for CuII or oxidation of CoII. Oxidation of CoII to CoIII complexes was only observed on the dissolution of CoII complexes in d6-DMSO in air while warming. The isolated solid complexes (CuII and CoII) have been characterized by elemental analyses, conductivities, spectral (IR, UV-Vis, 1H-NMR), thermal measurements (TGA), and magnetic measurements. The values of molar conductivities suggest non-electrolytes in DMF. The metal complexes are paramagnetic. IR spectra indicate that TPT is tridentate coordinating via the two pyridyl nitrogens and one triazine nitrogen forming two five-membered rings around the metal in M : L complexes and bidentate via one triazine nitrogen and one pyridyl nitrogen in ML2 complexes. In binuclear complexes, L is tridentate toward one CoII and bidentate toward the second CoII in [Co2(L1)Cl4]2.5H2O · EtOH and [Co2(L1)I4(H2O)3]. Electronic spectra and magnetic measurements suggest a distorted-octahedral around CuII and high-spin octahedral and square-pyramidal geometry around CoII.  相似文献   

4.
Summary Complexes of empirical formulae [ML2Cl2(OH2)2], [CoL2Br2(OH2)2]L·4H2O, [NiL2Br2(OH2)2]L2·2H2O, [ML2(OH2)4]L2(NO3)2 and [ML4(OH2)2](ClO4)2·2H2O (M = CoII, NiII, L = 2,4-bipyridyl) were synthesized and characterized by elemental and spectral analyses. The thermal decomposition of the complexes was also investigated.Author to whom all correspondence should be directed.  相似文献   

5.
Crystal Structures and Spectroscopic Investigations of Ternary CuII-Complexes with Bicyclic Dicarboxylic Acids and N,N-Donor Ligands The synthesis of coordination compounds [CuLdam] · 3H2O (H2L = 7-oxa-bicyclo[2.2.1]heptane-2-exo,3-cis-dicarboxylic acid ( 1 ) and its 1-methyl-derivative ( 2 ); dam = ethylendiamine, 1,2- and 1,3-propylendiamine, 2,2′-dipyridyl, 1,10-phenanthroline) has been described. Results of visible and IR spectroscopy and magnetic data are given. In the result of X-ray analyses of [CuL1dipy] · 3H2O ( 1 d ) and [CuL2en] · 3H2O ( 2 a ) the dicarboxylate anions of 1 and 2 proved to be tridentate chelating ligands. In 1 d the Cu atom has an approximately square-pyramidal coordination with the bridging O atom in the apical position. In 2 a , however, the coordination number is extended to six by an O atom of a second [CuL2en] unit resulting in a centrosymmetric complex dimer with octahedrally coordinated Cu atoms. The water molecules do not participate in the coordination of the Cu atoms and form a complicated system of hydrogen bonds in the crystal.  相似文献   

6.
Synthesis, Crystal Structures and Spectroscopic Investigations of 3d-Transition Metal Complexes with Bicyclo[2.2.1]hept-5-ene-2-endo,3-cis-dicarboxylic Acid and N,N-Donor Ligands The synthesis of coordination compounds of the general type [MLdam(H2O)3] · 2.5 H2O with M = Mn2+, Co2+, Ni2+; H2L = bicyclo[2.2.1]hept-5-ene-2-endo,3-cis-dicarboxylic acid and dam = 2,2′-dipyridyl, 1,10-phenanthroline has been described. The complexes have been characterized by elementary analysis, infrared and electronic spectra and magnetic susceptibility measurements. The results of X-ray crystal structure analyses of [MnLdipy(H2O)3] · 2.5 H2O ( 1 a ) and [CoLdipy(H2O)3] · 2,5 H2O ( 1 b ) show, that both compounds crystallize isotypically and prove the octahedral coordination of the metal atoms. The dicarboxylate anion is coordinated to the central atom by an O atom of only one carboxylate group, the other one is in the ionic state. One O atom of each carboxylate group makes an intramolecular hydrogen bond with a water molecule of the coordination sphere. The other crystal water molecules form a network of H bonds one with another and with the complex molecules, thus stabilizing the crystal packing.  相似文献   

7.
Structures of the complexes formed in aqueous solutions between zinc(II) and iodide ions have been determined from large-angle X-ray scattering, Raman and far-IR measurements. The coordination in the hydrated Zn2+ hexaaqua ion and the first iodide complex, [ZnI]+, is octahedral, but is changed into tetrahedral in the higher complexes, [ZnI2(H2O)2], [ZnI3(H2O)] and [ZnI4]2–. The Zn-I bond length is 2.635(4)Å in the [ZnI4]2– ion and slightly shorter, 2.592(6)Å, in the two lower tetrahedral complexes. In the octahedral [ZnI(H2O)5]+ complex the Zn-I bond length is 2.90(1)Å. The Zn-O bonding distances in the complexes are approximately the same as that in the hydrated Zn2+ ion, 2.10(1)Å.  相似文献   

8.
Controlled ozonolysis of 2,3,5,6-tetramethylidene-7-oxabicyclo[2.2.1]heptane ( 1 ) afforded 3,5,6-trimethylidene-7-oxabicyclo[2.2.1]heptan-2-one ( 2 ). Ozonolysis of 2 gave a 1:1 mixture of 3,5-dimethylidene-7-oxa-bicyclo[2.2.1]heptane-2,6-dione ( 3 ) and 3,6-dimethylidene-7-oxabicyclo[2.2.1]heptane-2,5-dione ( 4 ). The He(Iα) photoelectron (PE) spectra of 2 and 4 have been recorded. Comparison with the PE data of related systems, and with the result of ab initio STO-3G calculations, confirm the existence of significant through-bond interactions between the oxygen lone-pair orbitals n(CO) of the carbonyl functions and n(O) of the O(7) ether bridge.  相似文献   

9.
The [M(1-MeIm)2(H2O)4](Tpht) · 4H2O complexes (where M = Ni, Co; 1-MeIm is 1-methylimidazole; H2Tpht is terephthalic acid) are synthesized and characterized by X-ray diffraction analysis. The ionic structure is built of the [M(1-MeIm)2(H2O)4]2+ cations and (Tpht)2? anions. The metal ions have a distorted octahedral coordination. The cations and anions are united by hydrogen bonding system.  相似文献   

10.
Summary New complexes of the general formulae [MLA(H2O)2]-Cl2 (M=Ni or Cu), [MLAX2] (M=Co or Cu; X=Cl or Br), [NiLABr2]·H2O, [MLA] [MCl4] (M=Pd or Pt), [NiLB(H2O)2]Cl2·2H2O, [MLBCl2] (M=Co, Ni, Cu, Pd or Pt; X=Cl or Br) and [MLB] [MCl4] (M=Pd or Pt), where LA=N,N-ethylenebis(2-acetylpyridine imine) and LB=N, N-ethylenebis(2-benzoylpyridine imine), have been isolated. The complexes were characterized by elemental analyses, conductivity measurements, t.g./d.t.g. methods, magnetic susceptibilities and spectroscopic (i.r., far-i.r., ligand field,1Hn.m.r.) studies. Monomeric pseudo-octahedral stereochemistries for the CoII, NiII and CuII complexes andcis square planar structures for the compounds [MLBX2] (M=Pd or Pt; X=Cl or Br) are assigned in the solid state. The molecules LA and LB behave as tetradentate chelate ligands in the CoII, NiII, CuII and Magnus-type PdII and PtII complexes, bonding through both the pyridine and methine nitrogen atoms. A bidentateN-methine coordination of the Schiff base LB is assigned in the [MLBX2] complexes (M=Pd or Pt; X=Cl or Br). The anomalous magnetic moment values of the CoII complexes are discussed.  相似文献   

11.
New dinuclear complexes of the types [Ni2(L)(H2O)2] and [Ni2(L)(H2O)6] [H4L = N,N′‐bis(carboxymethyl) dithiooxamide (H4GLYDTO), N,N′‐bis(1‐carboxyethyl) dithiooxamide (H4ALADTO), N,N′‐bis(1‐carboxy‐2‐methylpropyl) dithiooxamide (H4VALDTO) and N,N′‐bis(1‐carboxy‐3‐methylbutyl) dithiooxamide (H4LEUDTO)] have been prepared and characterized by IR and electronic absorption spectroscopy, and the structure of [Ni2(ALADTO)(H2O)6] crystals has been determined by single crystal X‐ray analysis. This compound is composed of discrete dinuclear units in which two NiII atoms with NO4S kernels are linked by a single [ALADTO]4– group that coordinates through its carboxylato oxygen, amino nitrogen and thiolato sulphur atoms. In each dimer unit the two nickel(II) ions in distorted octahedral coordination are separated by 5.863(2) Å The temperature dependence of the magnetic susceptibility of the new compounds was measured over the range 2 to 300 K. In the complexes of [GLYDTO]4– and [ALADTO]4– the two Ni atoms are antiferromagnetically coupled, with J = –23.51(4) and –20.95(8) cm–1, respectively. By constrast, [Ni2(VALDTO)(H2O)2], [Ni2(VALDTO)(H2O)6] and [Ni2(LEUDTO)(H2O)2] remain paramagnetic down to 2 K, with magnetic moment values between 2.8 and 3.3 M.B.  相似文献   

12.
Summary Metal(II) complexes of 2-acetylthiophene-2-furoylhydrazone (HL) of the types [VO(HL)SO4], [Cu(HL)2Cl2(H2O)], [M(HL)2Cl2] [M=CoII, NiII, or ZnII] and [ML2(H2O)2] [M=CoII, NiII, CuII or ZnII] have been prepared and characterized on the basis of elemental analyses, molar conductance, magnetic susceptibility, visible, e.s.r. and i.r. spectral studies. The bonding and stereochemistry of the complexes are discussed.  相似文献   

13.
Two new trinuclear complexes [CuII(NiIIX1)2(C2H5OH)2]· (ClO4)2·2(CH3OH) ( 1 ) and [CuII(NiIIX2)2(H2O)]·(ClO4)2· 0.75(H2O) ( 2 ) (X1 = dianion of 5,6;13,14‐dibenzo‐7,12‐bis(ethoxycarboxyl)‐9‐methyl‐2,3‐dioxo‐1,4,8,11‐tetraazacyclotetradeca‐7,11‐diene. X2 = dianion of 5,6;13,14‐dibenzo‐9,10‐cyclohexano‐7,12‐bis(ethoxycarboxyl)‐2,3‐dioxo‐1,4,8,11‐tetraazacyclotetradeca7,11‐diene.) have been synthesized and characterized by single crystal X‐ray analysis, elemental analysis, IR, UV and EPR spectroscopies. The complexes consist of NiIICuIINiII heteronuclear cationic entities. The central CuII atom of 1 lies in an octahedral coordination environment, while that of 2 resides in a square‐pyramidal coordination sphere. The adjacent trinuclear units of 1 are linked together through π‐π stacking interactions resulting in a 1D supramolecular chain, whereas the π‐π stacking interactions between the contiguous units of 2 lead to a 2D structure. The EPR spectra of the two complexes show a signal of an axially elongated octahedral CuII system in 1 and an axially elongated square‐pyramidal CuII system in 2 , respectively. The hyperfine splitting of the CuII atoms (ICu = 3/2) has also been observed in the EPR spectra.  相似文献   

14.
Summary The reaction of aqueous solutions of 3d metal salts with bis(hydroxylammonium) bicyclo[2.2.1]-hept-5-en-endo-2,3-cis-dicarboxylate in a 12 mole ratio yielded complexes of the general formula [MnL2(NH3OH)2]·nH2O and [FeIIIL2(NH3OH)H2O]·H2O, where MII=Mn, Fe, Co, Ni, Cu and Zn, and L=bicyclo[2.2.1]-hept-5-en-endo-2,3-cis-dicarboxylate dianion.The compounds were characterized by i.r. spectra and thermal analysis. For all complexes, an octahedral structure is proposed which is formed bytrans coordination of two bidentate (OO) ligands (L) and two NH3OH+ cations attrans positions, coordinated also through oxygen atoms; and similarlytrans positions for NH3OH+ and H2O in the case of the FeIII complex.  相似文献   

15.
The compounds [Ni(H2O)2(En)2][{Ni(En)2}Re6S8(OH)6] · 7H2O (I), [{Cu(En)2}Re6S8(H2O)2(OH)4] · 4H2O (II), and [Ni(H2O)2(En)2]0.5[Re6Se8(H2O)3(OH)3] · 10H2O (III) were synthesized by layering aqueous solutions of Ni(En)2Cl2 or Cu(En)2Cl2 (En is ethylenediamine) onto aqueous solutions of the potassium salts of the corresponding octahedral chalcohydroxo rhenium cluster complexes [Re6Q8(OH)6]4− (Q = S, Se). The structure of the obtained compounds was determined by X-ray diffraction analysis.  相似文献   

16.
The complexes [Co(L)Cl2]Cl · 4H2O (1) and [Co(L)(N3)2]N3 · 2H2O (2) (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo [14,4,01.18,07.12]docosane) have been synthesized, and structurally characterized by X-ray crystallography, spectroscopy and cyclic voltammetry. The crystal structure of (1) is centrosymmetric and the cobalt(III) atom has an axially elongated octahedral geometry with four nitrogen atoms of the macrocycle and two chloride ligands. The cobalt(III) ion in (2) is coordinated to four nitrogen atoms from the macrocycle, and two azide ligands in an octahedral environment, which forms the 1D polymer through hydrogen bonding contacts involving the cation, azide anion and solvent water molecules. Electronic spectra of the complexes also exhibit a low-spin octahedral environment. Cyclic voltammetry of the complexes undergoes a one-electron wave corresponding to Co(III)/Co(II) processes. The electronic spectra and electrochemical behaviors of the complexes are significantly affected by the nature of the axial ligands.  相似文献   

17.
Three Cu(II) complexes constructed from 4-(2-pyridyl)-1H-1,2,3-triazole (L), namely, [CuL2Cl2]·H2O, [CuL2(CH3OH)(NO3)]NO3 and [CuL2(H2O)]SO4, have been synthesized and characterized. X-ray crystal structure analyses revealed that [CuL2Cl2]·H2O and [CuL2(CH3OH)(NO3)]NO3 have octahedral geometries, whilst [CuL2(H2O)]SO4 adopts a square-pyramidal coordination geometry. In all three complexes, the Cu(II) atoms are chelated by two L ligands in the basal plane, whilst the apical positions are occupied by Cl?, NO3?, CH3OH or H2O. The bandgaps between the HOMO and LUMO were estimated by cyclic voltammetry (CV) and diffuse reflectance spectroscopy (DRS) to be 3.43, 3.12, and 3.74 eV, respectively. Theoretical calculations on each structure gave similar results to the experiments. Frontier molecular orbital analyses showed that the higher electron density on the apical ligand, the lower the bandgap.  相似文献   

18.
New bi- and trihomonuclear Mn(II), Co(II), Ni(II), and Zn(II) complexes with sulfa-guanidine Schiff bases have been synthesized for potential chemotherapeutic use. The complexes are characterized using elemental and thermal (TGA) analyses, mass spectra (MS), molar conductance, IR, 1H-NMR, UV-Vis, and electron spin resonance (ESR) spectra as well as magnetic moment measurements. The low molar conductance values denote non-electrolytes. The thermal behavior of these chelates shows that the hydrated complexes lose water of hydration in the first step followed by loss of coordinated water followed immediately by decomposition of the anions and ligands in subsequent steps. IR and 1H-NMR data reveal that ligands are coordinated to the metal ions by two or three bidentate centers via the enol form of the carbonyl C=O group, enolic sulfonamide S(O)OH, and the nitrogen of azomethine. The UV-Vis and ESR spectra as well as magnetic moment data reveal that formation of octahedral [Mn2L1(AcO)2(H2O)6] (1), [Co2(L1)2(H2O)8] (2), [Ni2L1(AcO)2(H2O)6] (3), [Mn3L2(AcO)3(H2O)9] (5), [Co3L2(AcO)3(H2O)9] · 4H2O (6), [Ni3L2(AcO)3(H2O)9] · 7H2O (7), [Mn3L3(AcO)3(H2O)6] (9), [Co2(HL3)2(H2O)8] · 4H2O (10), [Ni3L3(AcO)3(H2O)9] (11), [Mn3L4(AcO)3(H2O)9] · H2O (13), [Co2(HL4)2(H2O)8] · 5H2O (14), and [Ni3L4(AcO)3(H2O)9] (15) while [Zn2L1(AcO)2(H2O)2] (4), [Zn3L2(AcO)3(H2O)3] · 2H2O (8), [Zn3L3(AcO)3(H2O)3] · 3H2O (12), and [Zn3L4(AcO)3(H2O)3] · 2H2O (16) are tetrahedral. The electron spray ionization (ESI) MS of the complexes showed isotope ion peaks of [M]+ and fragments supporting the formulation.  相似文献   

19.
The title compound, [CoCl(C12H8N2)2(H2O)]Cl·[CoCl2(C12H8N2)2]·6H2O, is the first example of a new 1:1 cocrystal of the octahedral [CoCl2(phen)2] and [CoCl(phen)2(H2O)]+·Cl complexes (phen is 1,10‐phenanthroline). The latter form heterochiral dimers held by strong π–π stacking interactions via their phenathroline ligands, which confirms that π stacking is an important and reliable synthon in supramolecular design. In addition, the crystal structure is networked by H2O...H2O, H2O...Cl and H2O...Cl hydrogen bonds, which interconnect the different units of the cobalt complexes.  相似文献   

20.
张曙光  冯云龙 《中国化学》2009,27(5):877-881
四唑酸(–CN4H)与羧酸(–COOH)具有相似的酸性。对苯酚四唑硫酮(H2L)可以作为单齿(–S或–N)或双齿(–N, N或–N, S)配体与金属离子配位形成配位化合物。合成了4个以H2L为配体的金属(II)配合物:Co(HL)2(Py)2(H2O)2 (1), [Mn(HL)2(H2O)4]·2H2O (2), Mn(HL)2(Phen)2 (3), and [Zn(HL)2(Phen)2]·0.5H2O·1.5CH3OH (4),并用X−射线单晶衍射法测定了晶体结构。晶体结构分析表明,在这些配合物中所有的中心金属原子均呈现六配位的八面体构型。在配合物1和2中,HL–配体以氧原子与中心金属原子配位,而在配合物3和4中HL–配体则以硫原子与中心金属原子配位。  相似文献   

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