A New Metal-organic Framework Constructed from Flexible Polycarboxylate Acid and Rigid Imidazole-based Ligands

A new complex, [Ni3(L)2(BTA)2]·2H2O (1, L=1,4-di(1H-imidazol-4-yl)benzene, H3BTA=benzene-1,3,5-triacetic acid), has been hydrothermally prepared and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis, TG and PXRD. The complex crystallizes in monoclinic, space group P1 with a=9.0303(12), b=10.0796(13), c=12.7966(17) , α=99.268(2), β=94.490(2), γ=103.722(3)o, V=1108.5(3) 3 , Z=2, C48H38N8O14Ni3 , Mr=1126.99, Dc=1.688 g/cm3 , μ=1.344 mm-1 , S=1.001, F(000)=578, the final R=0.0389 and wR=0.0895 for 3083 observed reflections (I > 2σ(I)). In the title complex, the flexible BTA3- ligands utilize oxygen atoms of carboxylate groups to coordinate with Ni(II) ions to form two-dimensional double-layer networks which are further pillared into a three-dimension framework via the rigid ditopic ligand L. Topological analysis revealed that complex 1 is a typical (3,8)-connected tfz-d 3D network based on the trinuclear [Ni3(CO2)6N4] subunits.     

Synthesis and Crystal Structure of Bis[2-[2-(diethylamino)ethyliminomethyl]-4-nitrophenolato]dimethanolcobalt(II) Dinitrate

1 INTRODUCTION The significance of cobalt coordination com- pounds in biological systems is recognized[1～3]. In many instances the cobalt coordination compounds of Schiff bases have been suggested as models to describe energy transfer in naturally occurring systems. In such cases the coordination sphere about the metal ion is believed to play an important role in determining the nature of the model system[4, 5]. In order to investigate the structures of such complexes, we report herein t…     

Synthesis and Crystal Structure of Di-μ_(1,1)-azido-bis((azido)[N-ethyl-N'-(1-pyridin-2-ylmethylidene)ethane-1,2-diamino]cadmium(Ⅱ))

The dinuclear Schiff base cadmium(II) complex [Cd2(C10H15N3)2(N3)2 (μ1,1-N3)2] was prepared and characterized by elemental analysis, IR spectrum, and single-crystal X-ray dif- fraction. The crystal belongs to the monoclinic system, space group P21/n with a = 10.819(2), b = 11.058(2), c = 12.766(3) , β = 102.456(2)o, V = 1491.3(7) 3, Z = 2, Dc = 1.665 g/cm3, Mr = 747.42, λ(MoKα) = 0.71073 , μ = 1.470 mm-1, F(000) = 744, R = 0.0307 and wR = 0.0584. A total of 3420 unique reflections were collected, of which 2575 with I > 2σ(I) were observed. There is a crystallographic inversion centre at the midpoint of the two metal atoms in the complex. Each CdII atom in the complex is in a distorted octahedral coordination. The molecules in the crystal are linked through the intermolecular hydrogen bonds of N–H···N and C–H···N, forming a three- dimensional network.     

Synthesis and Crystal Structure of Bis[O, O '-bis(4-tert-butylphenyl)dithiophosphate] nic kel(Ⅱ)

A new O,O'-bis(4-tert-butylphenyl)dithiophosphate complex Ni[SSP(OC6H4But- p)2]2 (1) was synthesized and characterized by elemental analysis, IR, 1H NMR, thermogravimetric analysis (TGA) and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 12.8440(3), b = 6.18686(12), c=26.3018(5) , β=92.6135(18)°, V = 2087.87(7) 3, Z = 2, Dc = 1.345 g/cm3, μ = 0.780 mm-1, the final R = 0.0316 and wR = 0.0748 (Ⅰ >2σ(Ⅰ)). A total of 4269 unique reflections were collected, of which 3621 with Ⅰ > 2σ(Ⅰ) were observed. The NiII atom lies on an inversion center and is chelated by two (p-ButC6H4O)2PSS-ligands in a [NiS4] square-planar geometry with Ni-S bonds of 2.2408(5) and 2.2444(5) , respectively. A stepwise 1D chain structure is constructed via intermolecular S…S and C-H…S interactions. According to our knowledge this is the first case that intermolecular S…S interaction is observed in mononuclear transition metal complex of O,O'-dialkyldithiophosphates.     

Synthesis and Crystal Structure of μ_(1,1,3) Formic Bridging 3D Microporous Ni(II) Complex

A μ1,1,3 formic bridging Ni2+ complex [Ni3(HCOO)6·H2O]]n 1 has been synthesi- zed under hydrothermal conditions. The single-crystal X-ray diffraction analysis shows that 1 exhibits a 3D open microporous tube formed by covalent and coordination bonds. Complex 1 crystallizes in the monoclinic system, space group P21/c with a = 11.1487(13), b = 9.7763(11), c =17.9685(17) , β = 126.948(6)o, C6H6Ni3O13, Mr = 462.02, V = 1565.2(3) 3, Z = 4, Dc = 1.961 g/cm3, μ = 3.630 mm-1, F(000) = 917.7, Rint = 0.0234, the final R = 0.0234 and wR = 0.0734 for 3469 observed reflections (I>2σ(I)).     

Syntheses and Crystal Structures of Two New One-dimensional Double Hydrogen-bonding-chain Complexes [Ni(bipy)_2Cl]·ClO_4 and [Zn(bipy)_2Cl]·BF_4

Two new transition metal complexes, [Ni(bipy)2Cl]·ClO4 (bipy = 2,2'-bipyridine) 1 and [Zn(bipy)2Cl]·BF4 2, have been synthesized and characterized by single-crystal X-ray diffraction analysis. Both 1 and 2 crystallize in monoclinic space group P21/n with Z = 4. For 1, a = 10.776(1), b = 12.067(1), c = 16.146(2) , β = 93.021(2)o, V = 2031.9(4) 3, Mr = 505.98, Dc = 1.654 g/cm3, μ = 1.255 mm–1, F(000) = 1032, the final R = 0.0406 and wR = 0.1002 for 3983 observed reflections with I > 2σ(I). For 2, a = 10.758(4), b = 12.058(4), c = 16.135(5) , β = 104.57(1)o, V = 2025.7(12) 3, Mr = 500.00, Dc = 1.639 g/cm3, μ = 1.396 mm–1, F(000) = 1008, the final R = 0.0470 and wR = 0.1237 for 3759 observed reflections with I > 2σ(I). The crystal structures of 1 and 2 are isostructural with very similar supramolecular structures. A one-dimen-sional zigzag double hydrogen-bonding-chain is generated by the intermolecular M-bipy ···anion···bipy- M hydrogen bonding interactions between the chelating ligands of bipy and anion.     

发光PtⅡ-CuⅠ异核配合物[Pt4Cu2(edt)4(PPh3)6](ClO4)2(4H2O)的合成及其表征

Self-assembly between Pt(phen)(edt) (phen=phenanthroline, edt=1,2-ethanedithiolate) and [Cu(PPh₃)₂(MeCN)₂](ClO₄) (PPh₃=triphenylphosphine) gave rise to formation of heterohexanuclear complex [Pt₄Cu₂(edt)₄(PPh₃)₆](ClO₄)₂(4H₂O) (1). The complex was characterized by elemental analyses, ES-MS, UV-Vis, IR, ³¹P NMR spectroscopy and X-ray crystallography. The molecule consists of two [Pt₂Cu(edt)₂(PPh₃)₃] units which has a centrosymmmetric inversion to give a cyclic heterohexanuclear skeleton. The Pt^Ⅱ and Cu^Ⅰ center adopt square-planar and trigonal coordination modes, respectively. The compound shows intense emission at 632 nm in the solid state and at 678 nm in frozen dichloromethane glass at 77 K.     

Synthesis, Crystal Structure and Cytotoxic Activity of a Novel Nickel(II) Complex with Schiff Base Derived from Salicylhydrazide

A novel Schiff base complex with π-conjugated system, [Ni(L1)2(py)2] 1 (L1 = (E)-N'-(2,4-dichlorobenzylidene)-2-oxidobenzohydraizide), was synthesized and characterized by elemental analysis and single-crystal X-ray determination. Complex 1 crystallizes in the monoclinic system, space group P21/n with a = 12.8286(10), b = 16.3573(13), c = 19.0206(14) , β = 108.2920(10)o, V = 3789.6(5) 3, Z = 4, Mr = 833.17, Dc = 1.460 g/cm3, μ = 0.843 mm-1, F(000) = 1704, the final R = 0.0537 and wR = 0.0640 for 3836 observed reflections with I > 2σ(I). In the molecular structure of 1, the NiII atoms are six-coordinated by two N and two O atoms from two Schiff base ligands (L1) and two N atoms from two pyridine solvent molecules to form a distorted octahedral geometry. The cytotoxic activities of complex 1 have been experimentally studied against a human HeLa cell in vitro.     

Synthesis and Structural Characterization of a Salt{[Co(Phen)3][Mo2S2(μ-S)2(edt)2]}2·(DMSO)2·(Et2O)(Phen = 1,10-Phenanthroline,edt = Ethane-1,2-dithiolate)

Reaction of [Et4N]2[Mo2S2(μ-S)2(edt)2] with CoCl2(6H2O and Phen in MeCN followed by recrystallization in DMSO/Et2O gave rise to dark-red block crystals of {[Co(Phen)3]- [Mo2S2(μ-S)2(edt)2]}2·(DMSO)2·(Et2O) 1 (C88H86Co2Mo4N12O3S18). 1 crystallizes in the monoclinic system, space group P21/c with a = 24.631(4), b = 16.117(3), c = 24.791(4) (A), β = 92.835°, V = 9829.3(3) (A)3, Z = 4, Mr = 2438.57, Dc = 1.648 g/cm3, F(000) = 4928, μ = 12.61 cm-1, R = 0.0936 and wR = 0.1682 for 12998 observed reflections with I > 2.0σ(I). In the structure of 1, the Co atom of the [Co(Phen)3]2+ dication is octahedrally coordinated by three Phen ligands. The Mo atom of the [Mo2S2(μ-S)2(edt)2]2- dianion is coordinated by two μ-S, one terminal S and two S atoms from edt, forming a distorted square pyramidal geometry. The mean Co-N and Mo…Mo bond distances are 2.139 and 2.872 (A), respectively.     

Syntheses and Crystal Structures of Two New Nickel（Ⅱ） Complexes with Salicylidene-2-ethanolamine

Two new Schiff base complexes of nickle(Ⅱ) [C18H20NiN2O4]·1.5H2O(1) and [C18H20N2NiO4]·H2O(2) were synthesized and characterized by elemental analysis,IR,UV-Vis and X-ray crystal structure analysis.Both 1 and 2 crystallize in the orthorhombic system.Crystal 1:space group Pbcn with a = 12.8591(19),b = 14.779(2),c = 19.749(3) ,V = 3753.3(10) 3,C18H23N2NiO5.5,Mr = 414.07,Z = 8,Dc = 1.445 g/cm3,μ = 1.067 mm-1,F(000) = 1712,S = 1.037,the final R = 0.0741 and wR = 0.2101 for 4353 observed reflections(I > 2σ(I)) and R = 0.1157 and wR = 0.2380 for all data.Crystal 2:space group P21 with a = 9.4673(17),b = 11.559(2),c = 16.347(3) ,V = 1788.9(6) 3,C18H22N2NiO5,Mr = 405.07,Z = 4,Dc = 1.497 g/cm3,μ = 1.116 mm-1,F(000) = 840,S = 1.085,the final R = 0.0330 and wR = 0.0869 for 3151 observed reflections(I > 2σ(I)) and R = 0.0362 and wR = 0.0887 for all data.Each Ni atom of 1 and 2 is six-coordinated with two nitrogen atoms and four oxygen atoms from two salicylidene-2-ethanolamine ligands yielding a distorted octahedral geometry.Dimer structure is observed in the packing diagram of 1.The thermal stability of complex 2 is also studied.     

Synthesis, Crystal Structure and Catalytic Behavior of 1-Ethyl-3-benyl-imidazolyl Tetranuclear N-Heterocyclic Carbene Silver Bromide

The title complex [Ag(carbene)2]2[Ag2Br4] has been synthesized by the reaction of Ag2O with 1-ethyl-3-benyl-imidazolium bromide in DMSO at room temperature, and characterized by elemental analysis, 1H NMR and single-crystal X-ray diffraction analysis. It crystallizes in triclinic, space group P with a = 10.1597(10), b =11.0646(11), c = 13.0245(14) , α = 102.230(2), β = 90.606, γ = 113.9250(10)o, V = 1300.3(2) 3, Mr = 748.06, Z = 2, Dc = 1.911 g/cm3, μ(MoKα) = 4.60 mm-1 and F(000) = 728. The structure was refined to R = 0.0316 and wR = 0.0835 for 3744 observed reflections with I > 2σ(I). The title compound crystallizes as a centrosymmetric tetranuclear compound. One half of the molecule comprises the asymmetric unit of the structure. The Ag(1) atom is nearly linear or T-shaped when the Ag(1)-Ag(2) interaction is taken into consideration, which is bi-coordinated by two carbene carbon atoms. The Ag(2) atom adopts tetrahedral geometry. The catalytic behavior of the title complex has been investigated, and the results indicate it has a highly catalytic activation for L-lactide polymerization.     

Synthesis and Structural Characterization of a Polyoxomolybdate HNa_7[Mo_(36)O_(112)(H_2O)_(16)]·47H_2O

A new polyoxomolybdate complex HNa7[Mo36O112(H2O)16]·47H2O 1 has been prepared in the beaker solution and characterized by single-crystal X-ray diffraction and elemental analyses. Crystal data: H127Mo36Na7O175, Mr = 6542.79, monoclinic, C2/c, a = 40.891(6), b = 17.900(3), c = 25.580(4) , β = 125.673(2)°, V = 15210(4) 3, Z = 4, Dc = 2.857 g/cm3, F(000) = 12464, μ = 3.013 mm-1, R = 0.0633 and wR = 0.1654 (I > 2σ(I)). With the bridging sodium cations, the [Mo36O112(H2O)16]8- units in compound 1 are linked to form a one-dimensional structure, on the basis of which a three-dimensional architecture is further constructed via other sodium cations and complicated hydrogen bonds.     

Synthesis and Structural Characterization of a Salt {[Co(Phen)_3][Mo_2S_2(μ-S)_2(edt)_2]}_2·(DMSO)_2·(Et_2O)(Phen = 1,10-Phenanthroline,edt=Ethane-1,2-dithiolate)

1 INTRODUCTION Dinuclear sulfido-bridged complexes with M2S2(μ-S)2 unit serving as building blocks for the construction of mixed-metal clusters are well docu- mented due to their rich structure diversities[1～3] as well as their potential applications in catalytic sys- tems and eletro/photonic materials[4, 5]. For example, reaction of [CpEt2Mo2S2(μ-S)2] with 2 equiv. of Co- (CO)3(NO) gave rise to a cubane-like cluster com- pound [CpEt2Mo2S2(μ-S)2Co2(CO)2][6]. In the case of[Mo…     

Active-site models for the nickel-iron hydrogenases: effects of ligands on reactivity and catalytic properties

Described are new derivatives of the type [HNiFe(SR)(2)(diphosphine)(CO)(3)](+), which feature a Ni(diphosphine) group linked to a Fe(CO)(3) group by two bridging thiolate ligands. Previous work had described [HNiFe(pdt)(dppe)(CO)(3)](+) ([1H](+)) and its activity as a catalyst for the reduction of protons (J. Am. Chem. Soc. 2010, 132, 14877). Work described in this paper focuses on the effects on properties of NiFe model complexes of the diphosphine attached to nickel as well as the dithiolate bridge, 1,3-propanedithiolate (pdt) vs 1,2-ethanedithiolate (edt). A new synthetic route to these Ni-Fe dithiolates is described, involving reaction of Ni(SR)(2)(diphosphine) with FeI(2)(CO)(4) followed by in situ reduction with cobaltocene. Evidence is presented that this route proceeds via a metastable μ-iodo derivative. Attempted isolation of such species led to the crystallization of NiFe(Me(2)pdt)(dppe)I(2), which features tetrahedral Fe(II) and square planar Ni(II) centers (H(2)Me(2)pdt = 2,2-dimethylpropanedithiol). The new tricarbonyls prepared in this work are NiFe(pdt)(dcpe)(CO)(3) (2, dcpe = 1,2-bis(dicyclohexylphosphino)ethane), NiFe(edt)(dppe)(CO)(3) (3), and NiFe(edt)(dcpe)(CO)(3) (4). Attempted preparation of a phenylthiolate-bridged complex via the FeI(2)(CO)(4) + Ni(SPh)(2)(dppe) route gave the tetrametallic species [(CO)(2)Fe(SPh)(2)Ni(CO)](2)(μ-dppe)(2). Crystallographic analysis of the edt-dcpe compund [2H]BF(4) and the edt-dppe compound [3H]BF(4) verified their close resemblance. Each features pseudo-octahedral Fe and square pyramidal Ni centers. Starting from [3H]BF(4) we prepared the PPh(3) derivative [HNiFe(edt)(dppe)(PPh(3))(CO)(2)]BF(4) ([5H]BF(4)), which was obtained as a ～2:1 mixture of unsymmetrical and symmetrical isomers. Acid-base measurements indicate that changing from Ni(dppe) (dppe = Ph(2)PCH(2)CH(2)PPh(2)) to Ni(dcpe) decreases the acidity of the cationic hydride complexes by 2.5 pK(a)(PhCN) units, from ～11 to ～13.5 (previous work showed that substitution at Fe leads to more dramatic effects). The redox potentials are more strongly affected by the change from dppe to dcpe, for example the [2](0/+) couple occurs at E(1/2) = -820 for [2](0/+) vs -574 mV (vs Fc(+/0)) for [1](0/+). Changes in the dithiolate do not affect the acidity or the reduction potentials of the hydrides. The acid-independent rate of reduction of CH(2)ClCO(2)H by [2H](+) is about 50 s(-1) (25 °C), twice that of [1H](+). The edt-dppe complex [2H](+) proved to be the most active catalyst, with an acid-independent rate of 300 s(-1).     

Syntheses, Crystal Structures and Properties of Two Supramolecules Assembled from Weak Interactions

Two complexes, [Cu2(Htdb)4(H2O)2] (1) and [Cd(bipy)2(Hmcmbc)2] (2) (H2tdb = 2,2-thiodibenzoic acid, H2mcmbc = m-(carboxyl-methyloxy)-benzenecarboxylic acid, bipy = 4,4'-bipyridine), have been prepared, and were characterized by elemental analysis, FT-IR and single-crystal X-ray diffraction. Structures indicate that complex 1 is a single molecule, and 2 is a one-dimensional chain. Their two-and three-dimensional frameworks are constructed through hydrogen bonding, π…π or C–H…π stacking, and such other weak interactions. The cyclic voltametric behavior of complex 1 and luminescence property of complex 2 were investigated. 1 belongs to the triclinic system, space group P with a = 7.8607(6), b = 11.7619(9), c = 15.3481(12) , α = 109.3670(10), β = 92.4420(10), γ = 92.0450(10)°, V = 1335.65(18) 3, Mr = 1256.26, Dc = 1.5619(2) g/cm3, F(000) = 642, μ = 1.029 mm–1, Z = 1, the final R = 0.0289 and wR = 0.0763 for 5199 observed reflections with I > 2σ(I). Complex 2 crystallizes in triclinic, space group P with a = 9.6378(10), b = 9.7508(10), c = 19.055(2) , α = 88.7020(10), β = 80.5260(10), γ = 69.2000(10)o, V = 1649.9(3) 3, Mr = 815.07, Dc = 1.641 g/cm3, μ = 0.732 mm-1, F(000) = 828, Z = 2, the final R = 0.0511 and wR = 0.1149 for 4729 observed reflections (I > 2σ(I)).     

Hydrothermal Synthesis,Crystal Structure and Magnetic Property of a New Co（Ⅱ） Complex：[Co（4,4＇-bpy）_2（H_2O）_2（4-FBA）_2]·（4,4＇-bpy）

A new complex [Co(4,4'-bpy)2(H2O)2(4-FBA)2]·(4,4'-bpy)(1) has been hydro-thermally synthesized using cobalt,4,4'-bipyridyl(4,4'-bpy) and 4-fluorobenzoic acid(4-HFBA),and characterized by thermal analysis,single-crystal X-ray diffraction and magnetic property.The complex crystallizes in the triclinic system,space group P,Z = 1.Crystal data:C54H44CoF2N8O6,Mr = 997.90,a = 9.134(2),b = 11.555(2),c = 12.867(3) ,α = 66.02(3),β = 77.96(3),= 73.11(3)°,V = 1180.9(4) 3,Dc = 1.403 g/cm3,μ(MoKα) = 0.433 mm-1,F(000) = 517,the final R = 0.0633 and wR = 0.1171 for 2152 observed reflections(I > 2σ(I)).The title complex is assembled into 1D supramolecular chains parallel to [001] based on the adjacent molecular ··· stacking interactions and hydrogen bonds.The variable temperature magnetic measurements show a weak ferromagnetic behavior over 300-160 K followed by antiferromagnetic behavior below 160 K for the title complex.     

Synthesis and Structure of an Iridium(Ⅲ)-ferrocenyl-dithiophosphonate Complex [{Fc(OCH_3)PS_2}Ir(cod)] (Fc=Fe(η~5-C_5H_4)(η~5-C_5H_5),cod=1,5 Cyclooctadiene)

The title complex [Fc(OCH3)PS2Ir(cod)] (1, Fc = Fe(η5-C5H4)(η5-C5H5), cod = 1,5-cyclooctadiene) has been prepared and characterized by X-ray diffraction analysis. It crystallizes in monoclinic, space group P21/n with a = 12.5567(5), b = 13.5197(5), c = 11.7833(4) , β = 99.651(2)°, V = 1972.06(13) 3, Z = 4, Mr = 611.52, Dc = 2.06 g/cm3, μ(MoKα) = 7.775 mm·1, F(000) = 1184, S = 1.063, the final R = 0.0199 and wR = 0.0468 for 4063 observed reflections with I > 2σ(I) and 227 variables. The molecular structure of 1 shows that the central iridium atom is chelated by the [Fc(OCH3)PS2]-ligand via two sulfur atoms and coordinated by one η4-cod molecule via four carbon atoms in a distorted octahedral coordination geometry. The average Ir-S and Ir-C bond lengths are 2.3712(8) and 2.122(3) , respectively.     

Construction of symmetric and asymmetric Mo/S/Cu clusters from a cluster precursor [Et4N]2[(edt)2Mo2S2(mu-S)2] (edt = ethanedithiolate)

Treatment of [Et 4N] 2[(edt) 2Mo 2S 2(mu-S) 2] ( 1) (edt = ethanedithiolate) with equimolar CuBr afforded an anionic hexanuclear cluster [Et 4N] 2[(edt) 2Mo 2(mu-S) 3(mu 3-S)Cu] 2.2CH 2Cl 2 ( 2.2CH 2Cl 2). On the other hand, reactions of 1 with 2 equiv of CuBr in the presence of 1,2-bis(diphenylphosphino)methane (dppm) and pyridine (Py) ligands gave rise to two neutral tetranuclear clusters [(edt) 2Mo 2O 2(mu-S) 2Cu 2(dppm) 2] ( 3) and [(edt) 2Mo 2O(mu 3-S)(mu-S) 2Cu 2(Py) 4] ( 4), respectively. The reaction of 1 with 2 equiv of CuBr followed by the addition of a mixture of dppm and Py (molar ratio = 1:2) yielded another neutral tetranuclear cluster [(edt) 2Mo 2(mu-S) 2(mu 3-S) 2Cu 2(dppm)(Py)].Py ( 5.Py). Compounds 2- 5 have been characterized by elemental analysis, UV-vis spectra, IR spectra, (1)H NMR, and X-ray analysis. The structure of the dianion of 2 can be viewed as having a [Mo 4S 8Cu 2] core in which two chemically equivalent [Mo 2(mu-S) 3(mu 3-S)(edt) 2Cu] (-) anions are linked by two extra Cu-S edt bonds. The molecular structure of 3 may be visualized as being built of one [(edt) 2Mo 2X 2(mu-S) 2] (2-) dianion and one [Cu 2(dppm) 2] (2+) dication that are connected by a pair of M-mu-S edt bonds. Compound 4 is formed by the affiliation of two Cu(I) atoms only at one end of the [(edt) 2Mo 2S 2(mu-S) 2] moiety, connecting with the S t atoms and the S edt atom. Cluster 5.Py can be viewed as being constructed from the addition of one Cu atom onto the incomplete cubanelike [Mo 2S 4Cu] framework through one terminal sulfur and one edt sulfur. Among the four clusters, 3 and 4 have internal mirror symmetry or pseudo mirror symmetry, respectively, while 2 and 5 are asymmetric clusters with racemic formation.     

Synthesis and Crystal Structure of a Ternary Complex:[Ni(phen)_2(pmal)]·8H_2O

1 INTRODUCTION Molecular structures of metallic complex and intermolecular weak interaction mode have become the focal fields of crystal engineering and supra- molecular chemistry. As we all known, intermole- cular weak interactions include hydrogen bonds[1, 2], π-π staking interaction[3, 4], metal-metal weak inte- raction[5, 6] and chelate-ring-chelate-ring weak inte- raction, et al.[7] Binary, ternary and quaternary car- boxylic acid ligands possess versatile coordination modes with me…     

A Novel Binuclear Cu（Ⅱ） Complex with Nitroxide Radicals Exhibiting Ferromagnetic Interactions

A new binuclear Cu(Ⅱ) complex with nitronyl nitroxide radicals [Cu(NIT3Py)2Cl2]2(NIT3Py = 2-(3'-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) has been synthesized and structurally characterized by X-ray diffraction analysis.It crystallizes in monoclinic,space group C2/c with a = 38.483(4),b = 7.2450(8),c = 27.559(3) ,β = 134.0180(10)°,V = 5525.6(10) 3,C48H64Cl4Cu2N12O8,Mr = 1206.00,Z = 4,Dc = 1.450 g/cm3,μ(MoKα) = 1.025 mm-1,F(000) = 2504,S = 1.066,the final R = 0.0471 and wR = 0.1121 for 3286 observed reflections(I > 2σ(I)).The title complex consists of centrosymmetric dinuclear units [Cu(NIT3Py)2Cl2]2,in which the copper ions are square-pyramidally coordinated by two pyridyl nitrogen atoms of two radical ligands and three chlorine anions,two of which bridge the copper ions.The magnetic measurements show ferromagnetic interactions between the copper ions and the radical ligands.