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1.
Several new coordination polymers of copper(II) with different carboxylate ligands containing siloxane units were synthesized by equilibrium polycoordination reactions of copper(II) acetate with the proper dicarboxylic acid (i.e. 1,3‐bis(3‐carboxypropyl)tetramethyldisiloxane, α,ω‐bis(3‐carboxypropyl)oligodimethylsiloxane, and 1,3‐bis(sebacomethyl)tetramethyldisiloxane) in solution (methanol), at room temperature. Some variations in the feed molar ratios were made. The resulting polymers having a polycoordination degree between 5 and 71 are soluble in a wide range of common organic solvents. The formation of polymers was proved by IR and UV–VIS absorption spectroscopy. The thermal behaviour of the coordination polymers was analysed by thermogravimetry in air. The silicon and copper contents and inherent viscosities were also determined. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
2.
《Journal of Coordination Chemistry》2012,65(9):1513-1524
A simple method for synthesis of manganese(II) coordination polymers with different benzoate ligands and pyridine N-oxide having general composition [Mn(RC6H4CO2)2(PyO)] n is presented (where PyO = pyridine N-oxide and R = H, 1a; R = 4-NO2, 1b; R = 4-Cl, 1c; R = 4-OH, 1d; R = 2-NO2, 1e). All these polymers are characterized by X-ray crystallography and other spectroscopic techniques. The coordination polymers have similar structures, but the positions of the manganese atoms differ. For example, 1c is highly symmetric and a mirror plane exists between each manganese site (2/m). In 1d, the manganese centers are related by an inversion center (?1) whereas in 1e the manganese centers are related by C1 rotation (1). Reaction of manganese(II) acetate tetrahydrate with 4-chlorobenzoic acid and PyO upon crystallization from methanol/pyridine gave crystals of coordination polymer 1c along with aqua-bis-pyridine bis-4-chlorobenzoato manganese(II) (2). The structure of 2 also determined by single-crystal X-ray diffraction has a 1-D hydrogen bonded chain structure. Temperature-dependent zero-field cooled and field-cooled magnetization data of 1a–1c measured at 20 Oe and 1000 Oe show field-dependent magnetization spread over a wide temperature range from 5 to 300 K. These coordination polymers show anti-ferromagnetic behavior below 20 K. 相似文献
3.
《Journal of Coordination Chemistry》2012,65(3):373-379
We report the structure and magnetism of a cobalt(II) compound with glycine acid, Co(C2H4NO2)2 · H2O (1). It crystallizes in the orthorhombic system, space group P2(1)2(1)2(1) with a = 5.2301(10) Å, b = 10.837(2) Å, c = 13.542(3) Å, R 1 = 0.0448, wR 2 = 0.1151. In 1, Co(II) has a slightly distorted square-pyramidal geometry defined by two O atoms and two N atoms from two glycine ligands, and by one O atom from an aqua ligand in the apical position. The molecules form a three-dimensional supramolecular network through O–H ··· O and N–H ··· O hydrogen bonds. Magnetic characterization shows 1 exhibits a negative Curie–Weiss constant and dominant spin-orbit coupling for Co(II). 相似文献
4.
Three transition-metal coordination polymers with azide and/or carboxylate bridges have been synthesized from 4-(3-pyridyl)benzoic acid (4,3-Hpybz) and 4-(4-pyridyl)benzoic acid (4,4-Hpybz) and characterized by X-ray crystallography and magnetic measurements. Compound 1, [Cu(4,3-pybz)(N(3))](n), consists of 2D coordination networks in which the uniform chains with (μ-EO-N(3))(μ-COO) double bridges are cross-linked by the 4,3-pybz ligands. Compound 2, [Cu(2)(4,4-pybz)(3)(N(3))](n)·3nH(2)O, consists of 2-fold interpenetrated 3D coordination networks with the α-Po topology, in which the six-connected dinuclear motifs with mixed (μ-EO-N(3))(μ-COO)(2) (EO = end-on) triple bridges are linked by the 4,4-pybz spacers. Compound 3, [Mn(4,4-pybz)(N(3))(H(2)O)(2)](n), contains 2D manganese(II) coordination networks in which the chains with single μ-EE-N(3) bridges (EE = end-to-end) are interlinked by the 4,4-pybz ligands, and the structure also features a 2D hydrogen-bonded network in which Mn(II) ions are linked by double triatomic bridges, (μ-EE-N(3))(O-H···N) and (O-H···O)(2). Magnetic studies indicated that the mixed azide and carboxylate bridges in 1 and 2 induce ferromagnetic coupling between Cu(II) ions and that 3 features antiferromagnetic coupling through the EE-azide bridge. In addition, compound 1 exhibits antiferromagnetic ordering below 6.2 K and behaves as a field-induced metamagnet. A magnetostructural survey indicates a general trend that the ferromagnetic coupling through the mixed bridges decreases as the Cu-N-Cu angle increases. 相似文献
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Ming-Ming Miao Dai-Zheng Liao Zong-Hui Jiang Geng-Lin Wang 《Transition Metal Chemistry》1995,20(5):445-447
Summary Four novel trinuclear copper(II) complexes have been synthesized, namely {[Cu(pbaOH)][Cu(L)]2}(ClO4)2, where pbaOH = 2-hydroxy-1,3-propanediylbis(oxamato) and L is 1,10-phenanthroline (phen), 5-nitro-1,10-phenanthroline (NO2-phen), 2,2-bipyridyl (bipy) or 4,4-dimethyl-2,2-bipyridyl (Me2bipy). Based on i.r. and electronic spectra, elemental analyses, and conductivity measurements oxamato-bridged structures consisting of three copper(II) ions, in which each copper(II) ion has a square-planar environment, are proposed. The temperature-dependent magnetic susceptibility of {[Cu-(pbaOH)][Cu(phen)]2}(ClO4) 2 has been studied in the 4.2–300 K range, giving the exchange integral J=- 111.9cm–1. The result revealed the operation of an antiferromagnetic spin-exchange interaction between adjacent copper ions. 相似文献
8.
Two transition metal coordination polymers {[Cu(tba)2(H2O)]·2H2O} n (1) and {[Mn(Htta)2(H2O)2]·2H2O} n (2) {Htba = 3-[1,2,4]triazol-1-yl-benzoic acid, H2tta = 2-[1,2,4]triazol-1-yl-terephthalic acid} have been synthesized under solvothermal conditions. Both complexes have been characterized by single-crystal X-ray diffraction, X-ray powder diffraction, elemental analysis and FTIR spectroscopy. Complex 1 has a 1-D chain structure in which Cu(II) atoms are doubly bridged by tba? ligands, which is further stabilized by hydrogen bonding and π–π stacking interactions to give a 3-D supramolecular framework. In complex 2, Mn(II) atoms are doubly bridged by Htta? ligands to form 1-D chains, which are further connected by intermolecular hydrogen bonds to form a 3-D supramolecular framework. The electronic spectra and thermal behaviors of complexes 1 and 2 are also reported. 相似文献
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10.
Guan‐Hua Wang Zhi‐Gang Li Heng‐Qing Jia Ning‐Hai Hu Jing‐Wei Xu 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(9):m333-m336
In the mixed‐metal complex catena‐poly[bis[diaquasilver(I)] [bis[aquacopper(II)]‐μ3‐pyridine‐2,5‐dicarboxylato‐2′:1:1′κ5N,O2:O5:O5,O5′‐μ‐pyridine‐2,5‐dicarboxylato‐2:1κ4N,O2:O5,O5′‐disilver(I)‐μ3‐pyridine‐2,5‐dicarboxylato‐1:1′:2′′κ5O5,O5′:O5:N,O2‐μ‐pyridine‐2,5‐dicarboxylato‐1′:2′′′κ4O5,O5′:N,O2] hexahydrate], {[Ag(H2O)2][AgCu(C7H3NO4)2(H2O)]·3H2O}n, a square‐pyramidal CuII center is coordinated by two N atoms and two O atoms from two pyridine‐2,5‐dicarboxylate (2,5‐pydc) ligands and a water molecule, forming a [Cu(2,5‐pydc)2(H2O)]2− metalloligand. One AgI center is coordinated by five O atoms from three 2,5‐pydc ligands and, as a result, the [Cu(2,5‐pydc)2(H2O)]2− metalloligands act as linkers in a unique μ3‐mode connecting AgI centers into a one‐dimensional anionic double chain along the [101] direction. The other AgI center is coordinated by two water molecules, forming an [Ag(H2O)2]+ cation. Four adjacent AgI centers are associated by Ag...Ag interactions [3.126 (1) and 3.118 (1) Å], producing a Z‐shaped Ag4 unit along the [010] direction and connecting the anionic chains into a two‐dimensional layer structure. This study offers information for engineering mixed‐metal complexes based on copper(II)–pyridinedicarboxylate metalloligands. 相似文献
11.
Two novel Mn(II) coordination polymers with azide and 4-(4-pyridyl)benzoic acid N-oxide (4,4-Hopybz) were synthesized and structurally and magnetically characterized. They are formulated as {[Mn(2)(4,4-opybz)(2)(N(3))(2)(H(2)O)(2)]·H(2)O}(n) (1) and {[Mn(4)(4,4-opybz)(5)(N(3))(H(2)O)(8)](N(3))(2)·2H(2)O}(n) (2). Compound 1 contains 2D coordination layers in which the infinite Mn(II) chains with alternating (μ-EO-N(3))(2)(μ-COO) (EO = end-on) and (μ-COO)(μ-O) bridges are interlinked by the backbones of the organic ligands. Compound 2 is a 3D metal-organic framework in which the unique linear tetranuclear clusters with (μ-EO-N(3))(μ-COO) and (μ-COO)(μ-O) bridges are cross-linked by organic backbones, and it represents a new example of the rare 8-connected self-catenated 3D net with the point symbol 4(16)·6(12). Magnetic analyses on the compounds have been performed in the classical-spin approximation, revealing that all the above-mentioned mixed bridging motifs induce weak antiferromagnetic interactions between Mn(II) ions. 相似文献
12.
Pardo E Carrasco R Ruiz-García R Julve M Lloret F Muñoz MC Journaux Y Ruiz E Cano J 《Journal of the American Chemical Society》2008,130(2):576-585
Self-assembly of the ligands N,N'-1,5-naphthalenebis(oxamate) (1,5-naba) and N,N'-2,6'-anthracenebis(oxamate) (2,6-anba) by Cu(II) ions affords the two new dicopper(II) metallacyclophanes 2a and 3b, whereby the metal centers are connected by double naphthalene- and anthracenediamidate bridges with alpha,alpha' and beta,beta' substitution patterns, respectively. Despite the largely different intermetallic distances of 8.3 A (2a) and 12.3 A (3b), magnetic susceptibility measurements show a moderately strong antiferromagnetic coupling with rather similar J values in the range from -20.5 to -20.7 (2a) and from -21.2 to -23.0 (3b) cm(-1) (H = -J S1 x S2; S1 = S2 = 1/2). Density functional theory calculations on the two series of dicopper(II) metallacyclophanes 1a-10a and 1b-10b with linear alpha,alpha'- and beta,beta'-disubstituted oligoacenediamidate bridges, respectively, confirm the better efficiency of the latter substitution pattern on long-range magnetic coupling. More importantly, they predict a unprecedented wirelike magnetic behavior for the longest members of the series with octacene through decacene spacers (J values up to +3.0 cm(-1) for intermetallic distances reaching 28.8 A). 相似文献
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Two new coordination polymers of Robson-type macrocycles, [Cu2L1(μ-ClO4)2]∞ (1) and [Cu2L2(μ-ClO4)2]∞ (2) (where H2L1and H2L2 are the [2+2] condensation products of 2,6-diformyl-4-flurophenol with 1,3-diaminopropane and 2-hydroxy-1,3-diaminopropane, respectively), have been synthesized and characterized. The intriguing feature is that intermolecular perchlorato bridges occur between adjacent copper(II) centers. The cyclic voltammograms of the complexes show that each complex undergoes two pseudo-reversible processes with the half wave potentials, −0.361 V and −0.729 V for 1, and −0.372 V and −0.744 V for 2, respectively. Magnetic susceptibility was measured for 1 and 2 over a temperature range of 2–300 K. The optimized magnetic data were J = −359.6 cm−1, j′ = −30 cm−1 and R = 6.8 × 10−8 for 1 and J = −411 cm−1, j′ = −26 cm−1 and R = 2.4 × 10−7 for 2, respectively. The data reveal antiferromagnetic couplings between the copper(II) ions of intra- and intermolecular units. 相似文献
15.
《Polyhedron》1995,14(4):521-527
Nickel(II) and copper(II) complexes MeL, where H2LL = [9-(2′-hydroxyphenyl)-6-methyl-3-acetyl-5,7,8-triazanona-3,6,8-trien-2-one], have been synthesized by template reaction of salicylaldehyde acetamidrazone with corresponding Me(acac)2 and Hacac in the presence of the orthoformic ester at 110°C. The crystal structure of CuL has been determined by X-ray diffraction. The square-planar mode of coordination is realized in CuL. Comparison of geometrical parameters of CuL with those of the corresponding derivative based on S--allylisothiosemicarbazide showed that substitution of the -SR group by methyl in the quadridentate ligand does not affect the mode of binding nor the main interatomic distances and angles in the ligand. The data from magnetic measurements, 1HH NMR and EI mass spectra indicate that NiL has a similarly structured coordination polyhedron. Epoxidation of norbornene can be performed efficiently with molecular oxygen (1 atm) in THF (or THF-EtOAc) in the presence of CuL at 70°C. The corresponding copper(II) derivatives based on S--substituted isothiosemicarbazides are much less active as catalysts. 相似文献
16.
Jing-Yun Wu Hui-Fang Chen Yu-Chen Jao Sheng-Ming Huang Tien-Wen Tseng Shie-Ming Peng 《Journal of solid state chemistry》2011,184(7):1740-1748
Two Cd(HBimc)-based isomers, [Cd(HBimcN)(HBimcT)(H2O)]·3.5H2O·EtOH (1a·3.5H2O·EtOH, H2Bimc=1H-benzimidazole-5-carboxylic acid) and [Cd(HBimcN)(HBimcT)(H2O)] (1b), and two Cu(HMBimc)-based coordination polymers, [Cu(HMBimcN)2(H2O)]·1/2H2O (2·1/2H2O, H2MBimc=2-methyl-1H-benzimidazole-5-carboxylic acid) and [Cu(HMBimcT)2]·2THF·H2O (3·2THF·H2O), were self-assembled from Cd(ClO4)2·6H2O/H2Bimc and Cu(ClO4)2·6H2O/H2MBimc systems, respectively. Compound 1a adopts a ladder-like chain structure, comprised of a hydrogen-bond-stabilized Cd2(HBimcN)2-metallocyclic stair and a 1D straight -(Cd-HBimcT)n- edge, whereas compound 1b exhibits a 2D (4,4)-rhombus layered structure, intercrossed by 1D -(Cd-HBimcN)n- chains and -(Cd-HBimcT)n- chains. Compound 2 shows a 1D double-stranded wave-like chain from two single-stranded wave-like -(Cu-HMBimcN)n- chains and compound 3 adopts a 2D (4,4)-topological layer structure, intercrossed by subunits of 1D -(Cu-HMBimcT)n- chains. Interestingly, a pair of tautomeric HBimc building blocks—normal (N or HBimcN) and tautomer (T or HBimcT)—is simultaneously included in the structures of 1a and 1b, whilst the N- and T-configured HMBimc building blocks are present as separate entities in Cu species, 2 and 3, respectively. The existence of only a tautomer (T) mode of the benzimidazolecarboxylate-based ligand in a Cu(II) network is observed for the first time. 相似文献
17.
Two new Co(II) coordination polymers with a pyridinedicarboxylate ligand, {[Co(L)(H(2)O)]·H(2)O}(n) (1) and [Co(3)(HCOO)(2)(L)(2)(H(2)O)(2)](n) (2) (H(2)L = 5-(pyridin-4-yl)isophthalic acid), have been synthesized and structurally characterized by elemental analysis, IR, XRPD, and single-crystal X-ray diffraction. Structure analyses show that complex 1 has a two-dimensional (2D) double-layered structure with a (3,6)-connected kgd topology based on [Co(2)O(2)] units, while complex 2 takes a three-dimensional (3D) structure with (3,6)-connected rtl topology network based on linear [Co(3)(HCOO)(2)(CO(2))(4)] clusters with triple carboxylate bridges. Magnetic investigation indicates that besides strong spin-orbit coupling of Co(II) ions, ferromagnetic and weak ferromagnetic exchange interactions between Co(II) ions in the Co(2) and Co(3) clusters exist in 1 and 2, respectively. The FC/ZFC magnetization behaviors for both of them suggest the absence of any long-range magnetic ordering. 相似文献
18.
Three one-dimensional (1D) azido-bridged coordination polymers of formula [Cu(L)(N3)2]n (1), [Cu2(Me-L)(N3)4]n (2), and [Mn(L)(N3)2]n (3) have been synthesized and structurally characterized, and their magnetic properties studied, where L and Me-L are 2-(pyrazol-1-ylmethyl)pyridine and 2-(3-methylpyrazol-1-ylmethyl)pyridine, respectively. Compound 1 consists of 1D chains in which the Cu(II) ions with a square pyramidal geometry are alternately bridged by an end-to-end (EE) and an end-on (EO) azido ligands, both adopting a basal-apical disposition. Compound 2 exhibits an unprecedented chain topology built via three different kinds of EO azido bridges. Four Cu(II) ions in the square pyramidal environment are alternately bridged by single and double EO bridges to form a tetranuclear cyclic ring, and neighboring rings are interlinked by double EO bridges to generate a "chain of rings". The intraannular double azido ions are disposed between metal ions in a basal-basal fashion, and the other two kinds of azido ions adopt the basal-apical disposition. Compound 3 consists of 1D concave-convex chains in which cis-octahedrally coordinated Mn(II) ions are alternately bridged by double EE and double EO bridges. There exist pi-pi interactions between the ligands bound to the neighboring Mn(II) ions bridged by the EO bridges. Temperature- and field-dependent magnetic analyses reveal alternate ferromagnetic interactions for 1, dominating ferromagnetic interactions for 2, and alternating ferro- and antiferromagnetic interactions through the EO and EE azido bridges for 3, respectively. 相似文献
19.
A total of 21 complexes of CuX (X = Cl, Br, I) with bridging ligand (B = 4,4'-dipyridyl (Bpy), pyrazine (Pyz), quinoxaline (Quin), phenazine (Phz), 1,4-diazabicyclo[2.2.2]octane (DABCO), and hexamethylenetetramine (HMTA)) have been synthesized. The products show two stoichiometries: [CuXB] (type 1) and [(CuX)2B] (type 2). Both types can be obtained for B = Bpy, depending on the conditions of preparation. In these cases, the type 2 stoichiometry is the kinetic product. Type 2 complexes only are found for B = Pyz (X = I), Quin, Phz, DABCO, and HMTA. Type 1 complexes form for Pyz (X = Cl, Br). Thermogravimetic analyses of the complexes reveal the general decomposition trend: 1 --> 2 --> [(CuX)2B(1/2)] --> CuX. The X-ray crystal structure of [CuBr(Pyz)] (type 1) features copper atoms bridged by Br and Pyz, forming 2D sheets of fused rectangular Cu4Br2(Pyz)2 units. The X-ray structure of [(CuI)2(Quin)] (type 2) shows 2D layers composed of [Cu2I2]infinity "stair step" chains which are cross-linked by Quin ligands. A total of 16 complexes of CuXL (L = P(OPh)3) with bridging ligand (B = those above and 1,4-dimethylpiperazine (DMP)) have also been prepared. All of these products, except those of HMTA, are of type 3 formulation, [(CuXL)2B]. The HMTA products have the formula [CuX(HMTA)], type 4. Thermal decomposition of the type 3 and 4 complexes occurs with initial loss of B, L, or both. The X-ray structures of [(CuBrL)2(Bpy)] and [(CuBrL)2(Pyz)] (type 3) reveal 1D chains formed from rhomboidal (LCu)2Br2 units linked by the B ligand. The type 4 structure of [CuBrL(HMTA)] is shown by X-ray to be a simple halide-bridged dimer. 相似文献
20.
Chang-Ge Zheng Song Li Pei-Pei Zhang Wan-Xia Wang Jian-Quan Hong Qian-Li Qian Xiu-Ying Chen 《Transition Metal Chemistry》2009,34(7):815-820
Three complexes, namely Zn(BDC-Cl4)(py)3 (1), Cu(BDC-Cl4)(py)3 (2) and Cd(BDC-Cl4)(py)3 (3) (BDC-Cl4 = 2,3,5,6-tetrachloro-1,4-benzenedicarboxylate, py = pyridine) have been synthesized. Complexes (1) and (2) have been obtained using solvothermal methods. Both have a five-coordinate geometry with two bridging monodentate tetrachloroterephthalate
ligands and three pyridine ligands coordinated to the Zn(II) or Cu(II) atom. The tetrachloroterephthalate ligands bridge the
adjacent Zn(II) or Cu(II) centers, giving zigzag chains. Complex (3) has also been crystallized, each Cd(II) atom is six-coordinated to three carboxylate oxygen atoms and three pyridyl nitrogen
atoms. Two types of tetrachloroterephthalate ligand, featuring monodentate and bidentate carboxylates, connect the Cd(II)
centers to form zigzag chains. All three complexes have been subjected to thermogravimetric analysis. 相似文献