Structures and magnetism of dinuclear Co complexes based on imine derivatives

This study presents the synthesis of three dinuclear cobalt complexes based on three imine derivatives:bis-[4-(2-pyridylmethyleneamino)-phenyl]thioether(L1),bis-[4-(2-pyridylmethyleneamino)-phenyl]ether(L2),and bis-[4-(2-pyridylmethyleneamino)-phenyl]methane(L3).Single-crystal X-ray diffraction analysis reveals that the complexes[Co_(2)(L1)3](ClO_(4))4·2CH_(3)CN(1),[Co_(2)(L2)3](ClO_(4))4·2CH_(3)OH(2),and[Co_(2)(L3)3](ClO_(4))4·2CH_(3)OH(3)all exhibit a dinuclear structure.Magnetic test results show that complex 3 exhibited irreversible SCO behavior induced by loss of solvent at 300 K,with the average Co-N bond length increasing from 0.2139(3)to 0.2153(3)nm.Meanwhile,the desolvated complex 3 exhibited paramagnetic behavior similar to that of complexes 1 and 2.Variable-temperature UV-Vis spectroscopic studies also indicate that complex 3 undergoes a solvent-loss-induced spin-state transition.CCDC:2347354,1(120 K);2347355,2(120 K);2347356,3(120 K);2347357,3(400 K).

Mixed-solvothermal Synthesis, Crystal Structure and Luminescence of a New Dinuclear Yttrium(Ⅲ) Coordination Polymer with 1-D Wave-like Infinite Chains

A new dinuclear Y（3＋） coordination polymer{[Y2（H2O）2（C（14）H8O4）3（C（12）H8N2）2]·3 H2O}n （1, C（14）H8 O4 = 2,2＇-biphenyldicarboxylate, phen = 1,10-phenanthroline）, has been obtained by means of a mixed-solvothermal method using ethylene glycol and water as solvent. The compound was characterized by elemental analysis, energy-dispersive X-ray spectroscopy（EDS）, IR spectrum and single-crystal X-ray diffraction. The results reveal that 1 belongs to monoclinic system, space group C2/c with a = 24.249（3）, b = 12.069（48）, c = 22.7304（08） A, β = 113.480（7）°, Z = 4, V = 6102（2） A3, Dc = 1.462 g·cm^-3, F（000） = 2728, μ = 1.968 mm（-1）, the final R = 0.0673, w R = 0.1508 and S = 1.085. Its structure can be regarded as a 1-D coordination polymer constructed by Y^3＋ cations, 2,2A-biphenyldicarboxylate, 1,10-phenanthroline and water molecules. The compound not only contains two kinds of organic ligands, but also exhibits interesting wave-like infinite chains and 18-MR windows with the diameter of 4.070（7）A × 5.326（9）A. The structure is further stabilized by means of O–H…O hydrogen bonds and π-π stacking interactions. Furthermore, the luminescent properties（including emission spectrum, CIE chromaticity coordinate and decay curve） of 1 were also investigated in the solid-state at room temperature.

Hydrothermal Synthesis,Crystal Structure and Thermal Analysis of a Dinuclear Complex Cd_2(3,5-Dinitrobenzoate)_4(pyridine)_4

A dinuclear complex Cd2（dnba）4（pyridine）4 （dnba = 3,5-dinitrobenzoate） has been synthesized by hydrothermal method and characterized by X-ray single-crystal diffraction, elemental analysis, FT-IR spectroscopy, DSC and TG-DTG techniques. The complex with empirical formula C48H32Cd2NI2024 （Mr = 692.83） crystallizes in monoclinic, space group P21/n with a - 12.0344（14）, b = 10.5752（13）, c = 21.578（3） A, β = 104.150（2）°, V = 2662.8（6） A^3, Z = 2, D, = 1.728 g/cm^3,μ（MoKa） = 0.897 mm^-1, F（000） = 1384, S = 1.016 and （△/σ）max = 0.001. R = 0.0638 and wR = 0.0737 for all data; the final R = 0.0337 and wR = 0.0644. In this complex, four carboxylates are bidentate-or chelate-coordinated with the Cd（Ⅱ） centers to give the dinuclear structure. The other coordination positions of Cd（Ⅱ） are occupied by the lone pair electrons from N of four pyridines. Thermal analyses DSC and TG-DTG have been used to determine the thermal decomposition mechanism of the title complex.

A New Dinuclear Zinc Polymer Based on 3-Methoxy-2-hydroxybenzaldehyde:Synthesis,Structure,Spectral Characterization and Hirshfeld Surface Analysis

A highly efficient fluorescence material dinuclear zinc polymer [Zn2（mhbd）2（dca）2]n （1, Hmhbd is 3-methoxy-2-hydroxybenzaldehyde, dca is N（CN）2？） has been synthesized under room temperature and structurally characterized by elemental analysis, IR, and single-crystal X-ray diffraction. The structure belongs to the triclinic system, space group P with a = 8.475（1）, b = 9.595（1）, c = 15.001（1） A, α = 86.84（1）, β = 81.10（1）, γ = 68.78（1）°, Mr = 565.15, V = 1123.5（1） ？3, Dc = 1.671 g？cm–3, F（000） = 568, μ = 2.185 mm–1, R = 0.0451, and wR = 0.1297. 1 is a dinuclear zinc complex which further constructs a 1D chain through double μ1,5-dca bridge. Luminescent property and Hirshfeld surface analysis of 1 have been studied. The result indicates that the fluorescence intensity of complex 1 is forty-one times the fluorescence intensity of Hmhbd ligand.

Synthesis, Crystal Structure, Fluorescence, Thermal Stability and Magnetic Properties of the Dinuclear Manganese(Ⅱ) Complex [Mn_2(L)_2(2,2'-bipy)_2(H_2O)_5]_2·3H_2O

A new dinuclear manganese complex [Mn2（L）2（2,2＇-bipy）2（H2O）512·3H2O has been synthesized with MnSO4·H2O, 2,2＇-bibenzoic acid （H2L） and 2,2＇-bipyridine（2,2＇-bipy） in the mixed solvent ethanol and water. It crystallizes in monoclinic, space group Pi with a = 9.9944（10）, b = 21.939（2）, c = 25.628（3） A, a = 108.429（3）, β = 100.613（4）, 7 = 102.821（3）°, V = 4997.9（9） A3, Dc= 1.355 g/cm^3, Z = 2, F（000） = 2108, GOOF = 1.074, the R= 0.0626 and wR= 0.1531. The structure of the complex contains two [Mn2（L）2（2,2＇-bipy）2] units, ten coordinated H2O molecules and three uncoordinated H2O molecules. The fluorescence, thermal stability and magnetic properties of the complex were investigated.

Crystal Structure,Fluorescence and Thermal Stability Properties of a Dinuclear Copper(Ⅱ) Complex[Cu_2(L)_2(phen)_2]-5H_2O(H_2L = Bicycle[2.2.1]hept-2-en-5,6-dicarboxylic acid)

A new dinuclear copper（II） complex [Cu2（L）2（phen）2]·5H2O （1） with bicycle[2.2.1 ]hept- 2-en-5, 6-dicarboxylic acid （H2L） and 1,10-phenanthroline （phen） as ligands has been synthesized in the mixed solvents of ethanol and water. It crystallizes in the monoclinic space group P21/c, with a = 17.925（4）, b = 19.908（4）, c = 11.235（2） A, β = 97.65（3）°, V= 3973.4（14） A3, Dc = 1.552 g/cm^3, Z = 8, F（000） = 1910, the final GOOF = 1.056, R= 0.0519 and wR= 0.1293. The crystal structure shows that the whole molecule consists of two independent dinuclear units, in which two copper ions are bridged by twoμ2-η1 ：η0-3-carboxylate groups of L^2- anions. The fluorescence and thermal stability properties of 1 were studied. The results show that 1 has an intense fluorescent emission at around 381 rim. The TG analysis shows that I is stable below 143 ℃.

Synthesis and Crystal Structure of a New Dinuclear Manganese(Ⅱ) Manganese(Ⅲ) Complex of a Macrocyclic Ligand

A mixed-valence dinuclear manganese complex, [Mn ⅡMn ⅢL](ClO 4)·1/2MeOH, where L is a macrocyclic ligand derived from the cyclocondensation of sodium 2,6-diformyl-4-methylphenolate with N,N-bis(2-aminoethyl)-2-hydroxybenzyl amine, was obtained and its structure was determined by X-ray diffraction. The orange crystal is a monoclinic system with space group P2 1/c and lattice parameters a=1.1617(4), b=1.4005(3), c=1.4641(3) nm, β=113.03(2)°, and Z=2. The crystal structure shows that each pendant-arm is bonded in a bidentate fashion to the adjacent metal atom and that both the arms are on the same side of the macrocycle. The two Mn atoms are bridged by two μ 2-phenoxy oxygen atoms of the tetra-imine macrocycle, and each Mn atom, locating in a trigonal prismatic coordination environment(N 3O 3), is six-coordinated by the two imine nitrogen atoms, one tertiary nitrogen atom and a pendant phenol moiety apart from the two oxygen atoms.

Solid-state Synthesis at Low-heating Temperature and Crystal Structure of a Dinuclear Molybdenum Complex with Oxalate Ligand[Bu_4N]_2[Mo_2O_2(OH)_2Cl_4(C_2O_4)]

The title compound was synthesized by the solid-state reaction of (NH_4)_6Mo_7O_(24)·4H_2O, Na_2C_2O_4, NH_2OH·HCl and Bu_4NBr at 90 ℃ for 10 h and crystallized from acetone-ether. The green crystal belongs to the monoclinic space group P2_1/n with a=9. 908(2), b= 17, 873(2), c= 13/450(2) A , β= 90. 09(1 )°,V = 2381. 6 (7 ) A￣3 , D_c = 1. 359 g/cm￣3 , Z= 2. The structure was refined to R =0. 0427 for 2562 reflections. The anion of the title compound can be described as an oxalate ligand (C_2O4￣2 ) bridging two [MoCl_2O(OH)] units, which contain Mo(V)atoms.

Hydrothermal Synthesis and Crystal Structure of a Novel Dinuclear Co(Ⅱ) Complex:[Co2(2,2'-bpy)_2(μ-L)_2(L)_2(μ-H_2O)](HL=4-Chlorobenzoic Acid)

A new 4-chlorobenzoic acid bridge Co（Ⅱ ） complex [[Co2（2,2＇-bpy）2（μ-L）e（L）2（μ-H2O）] （HL = 4-chlorobenzoic acid） has been obtained by hydrothermal synthesis, and X-ray single-crystal diffraction analysis shows that it crystallizes in the monoclinic system, space group C2/c with a = 22.537（5）, b = 16.212（3）, c = 15.306（3） A, β= 124.37（3）°, V= 4616.1（16）A3, Mr = 1070.45, Dc = 1.540 g/cm3, Z = 4, p = 1.012 mm-1, F（000） = 2176, the final R = 0.0338 and wR= 0.0810. The title complex is composed of dinuclear [Co2（2,2＇-bpy）2（μ-L）2（L）2（μ-HaO）] molecules. Each Co（Ⅱ ） atom is coordinated by two nitrogen atoms from one 2,2’-bipyridine ligand, three oxygen atoms from three 4-chlorobenzoic ions and another oxygen atom from one water molecule. The two Co（Ⅱ） atoms are connected by two 4-chlorobenzoic ions and one bridged water molecule. The dinuclear molecules are interlinked by hydrogen bond and π-π stacking interactions into a three-dimensional supramolecular network.

Synthesis and Characterization of a New Ligand 2-(4, 5-Dihydro-2-thiazolyl)-6-methoxylbenzothiazole and Its Dinuclear Co(II) Complex

A new ligand 2-（4,5-dihydro-2-thiazolyl）-6-methoxyl benzothiazole and its new dinuclear Co（II） coordination complex [Co（C11H10N2OS2）Cl2]2·2CHCl3 （1） have been synthesized and characterized. Complex 1 was synthesized by the reaction of Co（II） salt with 2-（4,5-dihydro- 2-thiazolyl）-6-methoxyl benzothiazole under room-temperature evaporation condition and struc- turally characterized by single-crystal X-ray diffraction analysis and IR spectroscopy. The supramolecular network of complex 1 is stabilized by the presence of intermolecular interaction, such as C-H···Cl hydrogen bonding and π-π stacking. The complex crystallizes in triclinic, space group P1 with a = 8.3288（12）, b = 10.5273（15）, c = 10.822（2）, α = 93.416（3）, β = 90.864（3）, γ = 94.890（3）o, V = 943.60（2）3, Z = 2, Dc = 1.758 g/cm3, F（000） = 498 and μ = 1.840 mm-1. The final complex [Co（C11H10N2OS2）Cl2]2·2CHCl3 is a diplex bridged dinuclear complex consisting of two Co（II） ions, two ligands, two bridging Cl- anions and two terminal Cl- anions.

Synthesis and Crystal Structure of a New Dinuclear Copper(II) Polymer: [Cu_2(bipy)_2(Hbtc)_2(H_2O)_2]·(H_2O)_(1/2)

A new dinuclear copper（Ⅱ） polymer [Cu2（bipy）2（Hbtc）2（H2O）2]·（H2O）1/2 1 （bipy = 2,2＇-bipyridine, H3btc = benzene-1,3,5-tricarboxylic acid） was obtained by the hydrothermal reaction of Cu（NOa）2·3H2O, bipy and H3btc. Compound 1 has been structurally characterized by single-crystal X-ray diffraction analysis and identified using elemental analysis and IR spectrum. The title complex crystallizes in monoclinic system, space group P21/c with a = 7.2880（5）, b = 18.4778（13）, c=13.5465（10）A,β = 95.958000）°, CI9HI4.50CuN207.25, M,. = 450.37, V= 1814.4（2）A^3, Z= 4, Dc = 1.649 g/cm^3, μ= 1.253mm^-1, F（000） = 918, Rint = 0.0185, the final R = 0.0271 and wR = 0.0710 for 2773 observed reflections （I 〉 2σ（I））. The study results reveal that a pair of distorted square-pyramidal Cu^2＋ ions are interlinked by bis-monodentate bridging Hbtc^2- ligands to constitute a 16-membered ring.

Synthesis and Structure of a New Dinuclear Uranyl Complex

With a heptadentate compartmental Schiff-base ligand H3L (1, 3-di[o-(salicylimino) ph- enoxyl]-2-propanol), a new binuclear diuranyl complex [(UO2)2L(OH)]?DMF, C38H45N5O13U2, was synthesized and the crystal structure was determined by X-ray diffraction techniques. The coordination geometry are two pentagonal bipyramids. In each pentagon four kinds of U-O (phenoxido, hydroxo, alkoxo and ether oxo) bonds are discussed.

Syntheses,Crystal Structures and Theoretical Calculation of Two Transition Metal Dinuclear Complexes

Two transition metal dinuclear complexes of [Mn2（OOCC6H4SSC6H4COO）- （Phen）2（H20）]n 1 and [CuE（OOCC6H4S）2（Phen）2] 2 were hydrothermally synthesized by the reaction of equivalent metal dichloride with 2,2＇-dithiobis（benzoic acid） （HE-DTBB）. Structure analysis indicates that each Mn2＋ ion in I is coordinated by one chelate phen ligand, one bridging water molecule and three DTBB ligands forming Mn2＋ dinuclear units which are further linked into one-dimensional chain by DTBB ligand. Under similar reaction conditions, the 2,2＇-dithio- his（benzoic acid） ligand undergoes thiol reduction to form 2-mercaptobenzoic （H-2-MBA） in 2 where two Cu2＋ ions are coordinated by phen and MBA ligands only constructing a dinuclear unit.

Synthesis and Characterization of A Dinuclear Europium Complex

A dinuclear Eu(Ⅲ) complex Eu2(DBM)6TPPD (Hexa(dibenzoyl-methanido)-(N, N, N, N-tetra(2-pyridyl)-1, 4-phenylenediamine)-dieuropium(Ⅲ)) was synthesized by employing DBM (dibenzoylmethane) and TPPD (N, N, N, N-Tetra(2-pyridyl)-1, 4-phenyl-enediamine) as sensitizing ligands for the Eu(Ⅲ) ion and a bridging ligand, respectively. The analysis of the absorption, excitation, and emission spectra of the dinuclear complex along with a comparison with analogous mononuclear complex containing the same β-diketone ligands and 1, 10-phenanthroline (phen) suggests that the dinuclear complex follows the luminescence mechanism of general Ln(Ⅲ) complexes.

Synthesis and Characterization of Two Novel High Valent Dinuclear Complexes with a Triphenolate Ligand Bearing Functional Groups

Two novel high valent complexes [M2(III, III)L(μ-OAc)2]·PF6 (M=Mn, Fe; 9) were prepared, where L was the tri-anion of 2,6-bis{[(2-hydroxy-3-(morpholin-4-yl methyl)-5-tert- butyl benzyl)(pyridyl-2-methyl)amino]methyl}-4-methyl phenol which contained additional phenolic, tert-butyl and morpholin-4-yl methyl groups compared to its parent [Mn2(II, II)(bpmp) (μ-OAc)2]·ClO4 (10). These improvements decreased the difference between the new model and (Mn)4 cluster (OEC in nature).

Synthesis and Crystal Structure of a Dinuclear Complex:Bis[aqua(phen)(4-aba)copper(Ⅱ)nitrate(4-abaH)dihydrate]

The title complex has been obtained by the reaction of copper nitrate trihydrate with 4-abaH （4-abaH = 4-aminobenzonic acid） and phenanthroline in ethanol solution, and its structure was determined by X-ray crystallography with the following data： monoclinic, space group C2/c, M, = 1266.13, Cu2C52H54N10O20, a = 25.884（5）, b = 10.205（2）, c = 20.849（4） A, β= 106.34（3）°, Z= 4, V= 5284.7（18） A^3, F（000） = 2616, Dc = 1.591 g/cm^3, μ = 0.896 mm ^-1, the final R = 0.0441 and wR = 0.1148 for 4200 observed reflections （Ⅰ 〉 2σ（Ⅰ））. In the molecule of the title complex, the asymmetric unit contains one half molecule, The Cu（Ⅱ） atom is five-coordinated by a tenninal water molecule, a bidentate phcnanthroline and two monodentate 4-ammobenzoate ligands forming a square pyramidal coordination environment. The two bridging 4-aminobenzoate ligands result in a dinuclear copper（Ⅱ） cluster with a short Cu-Cu distance （3.048 A） and a π-π rstacking between the adjacent phenanthroline rings （2.96 A）.

Synthesis and Structural Characterization of a Cyano-bridged Dinuclear Neodymium(III)-iron(III) Complex [Nd(DMSO)_5(H_2O)_2](μ-CN)[Fe(CN)_5]

A new neodymiumIII-ironIII complex [Nd(DMSO)5(H2O)2](μ-CN)[Fe(CN)5] (DMSO = dimethyl sulfoxide) has been synthesized by the grinding reaction method. The crystal belongs to monoclinic, space group P21/m with a = 8.859(4), b = 13.684(5), c = 12.290(4) ?, ?= 91.85(2)o, C16H34FeN6NdO7S5, Mr= 782.88, V = 1489(1) ?3, Z = 2, Dc = 1.746 g/cm3, S = 0.906, μ(MoKa) = 2.606 mm-1, F(000) = 788, R = 0.0646 and wR = 0.1654. The slightly distorted square-antiprism eightfold-coordinated Nd(III) and approximately oriented octahedrally sixfold- coordinated Fe(III) are linked by a cyano-bridge group to construct a dinuclear compound. The [Nd(DMSO)5(H2O)2](μ-CN)[Fe(CN)5] species are held together via hydrogen bonds to form a three-dimensional framework.

POLYMERIZATION OF ISOBUTYL VINYL ETHER CATALYSED BY DINUCLEAR HALF-TITANOCENES

Polymerization of isobutyl vinyl ether(IBVE)has been studied with mononuclear half-titanocene,CpTiCl_3[1]and dinuclear half-titanocenes,[(C_5H_4)_2(CH_2)_n][(TiCl_3)_2][2(n=3),3(n=6)],and[(C_5H_4)_2(CH_2)_n[(TiCl_2OR_2](R=2,6- diisopropylphenoxyl)[4(n=3),5(n=6)],in the presence of methyl aluminoxanes(MAO)as cocatalyst in methylene chloride.The influences of the length of polymethylene brigde and the substitution of aryloxy group at the metal center have been investigated at three polymerization temperature(...

Synthesis, Crystal Structures and Catalysis of Dinuclear Cd(Ⅱ) Complexes Bridged by Unusual (N,O,O′)-Coordinated α-Amino Acids

Four dinuclear amino acid cadmium（II） complexes [Cd2（tren）2（dl-alaninato）]（ClO4）3·H2O（I）, [Cd2（tren）2· （l-alaninato）]（ClO4）3·H2O（II）, [Cd2（tren）2（dl-phenylalaninato）]（ClO4）3（III） and [Cd2（tren）2（l-phenylalaninato）]· （ClO4）3（IV）, constructed from mixed ligands of tris（2-aminoethyl）amine（tren） and racemic or natural amino ac ids（amino acids=dl or l-alanine, and dl or l-phenylalanine）, have been synthesized and characterized by X-ray crys tallography. The structural analysis of complexes I and III reveals that the cadmium centers are coordinated by one tren ligand and one amino acid molecule with the unusual （N,O,O′）-bridged mode, resulting in asymmetric chromo phores of CdN4O and CdN5O in complex I, CdN4O2 and CdN5O in complex III, respectively. The utility of the four complexes as efficient water-compatible Lewis acid catalysts for the direct aldol reaction in water was examined. The reaction proceeded smoothly to afford the corresponding β-hydroxy ketones in up to 99% yield. Moreover, the dias tereoselectivity of the reaction favors the formation of the syn-isomers.

Hydrothermal Synthesis,Crystal Structure and Electrochemical Properties of a New Dinuclear Copper Complex [C_2H_6ON]_2[Cu_2Cl_2(μ-CH_3COO)_4]

The hydrothermal reaction of copper chloride dihydrate and 5,5-dimethyl-imidazolidine,-2,4-dione with a mole ratio of 1：1 in acetonitrile resulted in the formation of a new acetate-bridged dinuclear copper complex, [C2H6ON]2[Cu2Cl2（μ-CH3COO）4]. Protonated acetamide in eaolie form and acetic acid were yielded by the hydrolysis of acetonitrile under hydrothennal condition. The rifle complex （C12H24Cl2Cu2N2O10） was characterized by X-ray single-crystal diffraction, IR spectrum, elemental and electrochemical analysis. It crystallizes in the monoclinic system, space group P21/c with a = 8.298004）, b = 14.358（2）, c = 12.0010（2） A^°, β= 130.620（3）°, V = 1085.3（2） A^°^3, Dc = 1.696 g/cm^3, 34, = 554.31, Z = 2, F（000） = 564 and μ = 2.254 mm^-1. The crystal structure consists of a tetraacetate-bridging dinulcear copper complex anion [Cu2Cl2（μ-CH3COO）4]^2-, with the chlorine anions in the axial positions, and two protonated acetamide cations [C2H6ON]^＋, which were connected through hydrogen bonds to form a three-dimensional infinite network.