Structures and Properties of Two Pillared-layer Mn(Ⅱ) MOFs with 5-Ethyl-pyridine-2,3-dicarboxylate

The reaction of Mn(OAc)2·4 H2 O, 5-ethyl-pyridine-2,3-dicarboxylic acid(H2 epda) and 4,4?-bipyridine(4,4?-bipy)/4,4?-bis(imidazolyl)biphenyl)(bibp) under hydrothermal conditions produced two new manganese(Ⅱ) MOFs [Mn(epda)(4,4?-bipy)1/2](1) and [Mn(epda)(bibp)1/2](2), which were characterized by elemental analysis, infrared spectroscopy, thermogravimetric analyses, and single-crystal X-ray diffraction. The structures of complexes 1 and 2 are similar. In 1, the adjacent Mn(Ⅱ) ions are connected by epda dianion to generate a 2 D(4,4) grid layer, and such 2 D layers are further connected via bibp ligand to form another layer, forming a 2 D pillared-layer. Topologically, the Mn atoms as the node are bridged by the edpa anions and bibp ligands to form a uninodal 5-connected network topology. The magnetic properties of 1 and 2 have also been-investigated, and the exchange interctions were –1.39 and –1.05 cm1, respectively. According to the crystal structures, compounds 1 and 2 were carried out by using hybrid DFT methods at the B3 LYP/6-31 G(d) level. The DFT-BS approach was applied to study the magnetic coupling behaviors for 1 and 2. The result reveals that the calculated exchange coupling constants J were in good agreement with the experimental data.     

Three New Zn(Ⅱ)/Cd(Ⅱ) Coordination Polymers Constructed with 2-Mercaptonicotinic Acid and 1,2-Di(4-pyridyl)ethylene: Syntheses and Structure Analysis

Three new Zn(Ⅱ)/Cd(Ⅱ) coordination polymers based on 2-mercaptonicotinic acid (H2mna) with 1,2-di(4-pyridyl)ethylene (dpe) introduced as a bridging ligand have been synthesized via hydrothermal method and structurally characterized by single-crystal X-ray diffraction as well as elemental analysis and IR. As reported in this paper, [Zn2(dpe)0.5(mna)2] (1) can be classified as a two-dimensional layer structure in which the 1D chain composed of Zn(Ⅱ) and mna ligands is bridged by dpe ligands, while the complex named [Zn4(dpe)4(mna)4] (2) is a tetra-nuclear cluster compound. These two compounds are further extended to three-dimensional structures by hydrogen bonds along with C-H…π and π…π interactions. Compound 3 with general formular [Cd2(dpe)0.5(mna)2]·H2O belongs to a three-dimensional porous structure in which the 2D metal layers formed by the coordination of Cd(Ⅱ) and mna ligands are connected with the bridging of dpe ligands.     

Hydrothermal Synthesis,Crystal Structure and Characterization of a New Keggin Polyoxometalate {[Ag~I(4,4’-bipy)]_3[PW_(12)O_(40)]}·(4,4’-bipy)

A novel polyoxometalate {[AgI(4,4'-bipy)]3[PW12O40]}·(4,4'-bipy)·4H2O 1 has been synthesized hydrothermally and characterized by elemental analysis, IR and single-crystal X-ray diffraction. The crystal of 1 belongs to the triclinic system, space group P1 with a = 11.3710(17), b = 12.0701(16), c = 13.1061(12) , α = 112.838(3), β = 94.545(6), γ = 99.526(4)°, V = 1614.4(4) 3, Mr = 3825.40, Z = 1, Dc = 3.935, μ = 22.289mm-1, F(000) = 1692, the final R = 0.0507 and wR = 0.1054. X-ray diffraction analysis reveals that the molecular structure of 1 consists of three coordinated cations [AgI(4,4'-bipy)]+, a polyanion unit [PW12O40]3-, and a discrete 4,4′-bipy molecule. Significantly, there exist two crystallographically independent silver(I) centers in 1 and all [AgI(4,4'-bipy)]+ cations are linked with each other to form a one-dimensional Ag-4,4'-bipy polymer chain. The neighboring polymer chains are further interconnected to form a 3D framework by the covalent effect of silver atoms and terminal oxygen atoms of the polyanion. The electrochemical behaviors of 1 have also been studied in detail by cyclic voltammograms.     

Polymeric Structure and Solid ~(31)P, ~(113)Cd NMR Spectra of Cadmium(II) Dialkyldithiophosphate (Alkyl = n-butyl and i-butyl)

Owing to the particular affinity toward metal ion and changeable dentation, dialkyldithiophosphates are commonly used ligands in preparation of the transition metal complexes with variable structures1. For instances relevant to this work, the IIB metal complexes defined crystallographically so far have provided the examples as follows2-12 (Scheme 1). Scheme 1 The frameworks of IIB metal complexes of dialkyldithiophosphate MMMMMMMMMM a b c d …     

Syntheses,Crystal Structures and Catalytic Properties of Copper(Ⅱ) and Cobalt(Ⅱ) Complexes Containing 5,6-Dimethylbenzimidazole

Two new complexes, [Cu(DMB)2(NAA)2](1) and [Co(DMB)2(NAA)2](2)(DMB = 5,6-dimethylbenzimidazole, HNNA = 1-naphthylacetic acid), were hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy, TGA, PXRD and single-crystal X-ray diffraction analysis. The coordination geometry of the metal centers is a perfect square plane for 1 and a distorted tetrahedron for 2. In compound 1, the mononuclear units are linked by N–H···O hydrogen bonds to form a 1D chain structure, while mononuclear motifs of 2 are extended via N–H···O hydrogen bonding and π-π stacking interactions into a 2D supramolecular layer. The remarkable catalytic properties of the two complexes for the degradation of Congo red dye have been found.     

The Study on the Stability Constant and Species Distribution of Eu （Ⅲ） and Tb （Ⅲ） Complexes with BDBPH

The stability constants and species distributions of complexes of two lanthanide ions, Eu（Ⅲ） and Tb（Ⅲ）, with a macrocyclic ligand, BDBPH, in 1：1 and 2：lsystem, were determined potentiometrically at 25.0 ℃ and I=0.100 mol L^-l. The two metal ions could form deprotonated mono- or dinuclear complexes with BDBPH after the first two protons of the ligand completely neutralized. At higher pH values, Eu（Ⅲ） could not form hydroxy complexes with BDBPH, while Tb（Ⅲ） could form hydroxy complexes in the type of M2L（OH）, M2L（OH）2, and M2L（OH）3.     

Metallotricycle of Lanthanide Supported by a Bridging Diamide: Syntheses and Molecular Structures of {Li(THF)3[LnCl(μ2-trans-1,2-(NSiMe3)2C6H10)(μ2-Cl)]}2•2THF (Ln＝Yb, Nd)

The reactions of dilithium salt of trans-1,2-bis（trimethylsilylamino）cyclohexane with anhydrous lanthanide trichlorides LnCl3 （Ln = Yb, Nd） in THF afforded the dianionic binuclear tricycles of lanthanide chlorides {Li（THF）3[LnCl（μ2-trans-1,2-（NSiMe3）2C6H10）（μ2-Cl）]}2·2THF （Ln=Yb 1, Nd 2） in moderate yields. Both of the bridged complexes were characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. Crystal structural analysis shows that the two complexes are the analogues which have a tricyclic framework built by two bridged lanthanide metals, four nitrogens and four carbons from two diamide ligands. Each lanthanide metal coordinates to three nitrogen atoms and two chlorines to form a distorted trigonal bipyramid and connects with a lithium by a bridging chlorine.     

Synthesis and Characterization of an Unexpected Asymmetric Binuclear Copper(I) Complex Containing 4-Vinyl-pyridine

Introduction Many examples of complexes containing the eight-membered ring M(-dppm)M' are known with a variety of metals, oxidation states and stereochemis-tries.1-4 In general, they contain trans-bound, bridging dppm ligands to give a planar M2P4 core structure with the two metal atoms held in close proximity to each other (regardless of whether a metal-metal bond is pre-sent or not). This feature is presumably one of the chief reasons for the unusual bonding, reactivity and catalytic prope…     

Crystal Structure and Property Research on Compounds Co（Ⅱ） and Zn（Ⅱ） with 3-Methylbenzoic Acid

Two compounds with 3-methylbenzoic acid(HL) [Co(L)2(4,4'-bipy)]n 1 and [Zn2(L)4(4,4'-bipy)]n 2(L = 3-methylbenzoic acid) have been hydrothermally synthesized directly and characterized by single-crystal X-ray diffraction analysis,elemental analyses,IR spectra and ultraviolet-visible diffuse reflection integral spectra(UV-Vis DRIS).The two compounds are both one-dimensional infinite chains.The structural difference is that 1 is a double-chain structure and 2 is only a single chain one.At the same time,the carboxylate groups adopt different modes in the two compounds,relatively.Additionally,in order to explore the structural characteristic,two-dimen-sional IR spectra are investigated for 1 and 2.Photo-luminescent property of 2 is also researched in detail.     

铜(Ⅱ)离子导向的自组装研究

A few copper(Ⅱ) ions or groups have been designed and investigated for metal-assisted self assembly. Reactions of these metal units with a number of linear bridging ligands have led to the production of some dinuclear copper(Ⅱ) complexes and coordination polymers in which metal centers are all five-coordinate in the configuration of a square pyramid or a triangular bipyramid.     

Syntheses and Structures of Two Isomorphous Metal-organic Coordination Complexes Based on 4-Pyrimidin-5-ylbenzoic Acid

The reactions of 4-pyrimidin-5-ylbenzoic acid （HL） with Co（NO3）2·6H2O and Ni（NO3）2·6H2O gave rise to two isomorphous mononuclear coordination complexes, namely, [CoL2（H2O）4] （1） and [NiL2（H2O）4] （2）. Both compounds were characterized by IR spectroscopy and single-crystal X-ray diffraction. X-ray crystallographic analyses reveal that they crystallize in monoclinic, space group P21/n. In the crystal structures of these two complexes, only one nitrogen atom of L coordinates to the metal center, and neither carboxylate group nor another nitrogen atom of L links to Co（Ⅱ） or Ni（Ⅱ）. 2D Layers with significant hydrogen bonds can be observed, and they are further linked by L to form a 3D supramolecular network. Nitrogen atoms are not involved in forming hydrogen bonds, but carboxylic groups of the ligands play an important role in the configuration of this hydrogen-bond layer.     

Synthesis and Crystal Structure of [Cis-1,10phenanthroline-palladium(Ⅱ)(THF)_2]dinitrate (THF = Tetrahydrofuran)

1 INTRODUCTION The coordination chemistry of Pd(Ⅱ) com- plexes with didentate nitrogen coordination ligands has been extensively studied for a few decades[1]. Pd(Ⅱ) trends to bond to the didentate nitrogen in cis-mode and such complexes have potential usage in the emerging area of self-assembly[2]. We will report herein the synthesis and crystal structure of a cis-coordinated mononuclear Pd(Ⅱ) complex with one 1,10-phenanthroline and two THF as ligands, 1. 2 EXPERIMENTAL 2. …     

Polymerization of styrene by Novel Ni(Ⅱ)- and Pd(Ⅱ)-based complexes

The catalytic activities of nine neutral nickel and palladium a-acetylide complexes [M=(C=CR)2(PR'3)2)M=Ni,Pd; R=Ph,CH2OH,CH2OOCH3,CH2OOCPh,CH2OOCPhOH-o; R'=Ph,Bu] are compared.Among them,Ni(Cs=CPh)2-(PBuj)2 shows the highest catalytic activity and gives the polystyrene with high molecular weight(Mw=188800)and a syndio-rich microstructure.The catalytic behavior of transition metal acetylides is related to metal,phosphine,and alkynyl ligands bonded to the metal atoms.     

Synthesis, Spectroscopic and Electrochemical Investigations of Two vic-Dioximes and Their Mononuclear Ni（Ⅱ）, Cu（Ⅱ） and Co（Ⅱ） Metal Complexes Containing Morpholine Group

Two vic-dioxime ligands （LxH2） containing morpholine group have been synthesized from 4-[2-（dimethylaminoethyl）] morpholine with anti-phenylchloroglyoxime or anti-monochloroglyoxime in absolute THF at -15 ℃. Reaction of two vic-dioxime ligands with MCl2·nH2O （M： Ni, Cu or Co and n=2 or 6） salts in 1 ： 2 molar ratio afforded metal complexes of type [M（LxH）2] or [M（LxH）2·2H2O]. All of metal complexes are non-electrolytes as shown by their molar conductivities （Am） in DMF （dimethyl formamide） at 10^-3 mol·L^-1. Structures of the ligands and metal complexes have been solved by elemental analyses, FT-IR, UV-Vis, ^1H NMR and ^13C NMR, magnetic susceptibility measurements, molar conductivity measurements. Furthermore, redox properties of the metal complexes were investigated by cyclic voltammetry.     

A Corrugated 2D Mn(Ⅱ) Network:[Mn_3(μ-oxalate)_3(μ-4,4'-bpy)_2(4,4'-bpy)_2]_n

1 INTRODUCTION It is well known that the bi-functional 4,4?-bi- pyridine (4,4?-bpy) has the ability to act as a rigid, rod-like organic building block in the self-assembly of coordination frameworks. Many researches have also been done on the metal oxalate compounds. The remarkable coordination abilities of oxalate and 4,4?- bpy ligands are applied to design and synthesize new polymeric coordination complexes[1～4] containing mixed bridging ligands. Manganese is one of the several first-r…     

Syntheses and Crystal Structures of Two New Mercury（Ⅱ） Complexes with Double Betaine Ligands

Reaction of HgCl2 and double betaine ligands in water at about 80 ℃ yielded two new Hg(Ⅱ) complexes,[Hg(L1)Cl2]·H2O 1 and [Hg2(L2)Cl4]·3HgCl2 2(L1 = 1,3-bis(pyridinio-4-carboxylato)-propane,L2 = 1,4-bis(pyridinio-4-carboxylato)-1,4-dimenthylbenzene).Their struc-tures have been characterized by single-crystal X-ray diffraction techniques.The structure of 1 contains 1-D chains,in which the adjacent Hg(Ⅱ) atoms are bridged by L1 ligands in a syn-syn bis-monodentate mode.The chains are further connected through face-to-face π-π stacking interactions between pyridine rings to generate an infinite double-chain network.In 2,two Hg(Ⅱ) atoms are joined by L2 ligands in the same coordination mode as 1 to form an isolated dinuclear structure.The thermal stabilities of both complexes have also been investigated.     

Synthesis,Crystal Structure and Magnetic Properties of a Coordination Polymer Based on Iron(Ⅱ) Carboxylate Helical Chains [Fe(bpdc)(H_2O)_2]n

A coordination polymer based on iron(II) carboxylate helical chains [Fe(bpdc)(H2O)2]n 1 has been constructed hydrothermally using H2bpdc (H2bpdc = 2,2'-bipyridine-4,4'-dicarboxylic acid), pyridine and FeSO4·7H2O. Its crystal structure reveals that the Fe(Ⅱ) ion adopts a slightly distorted octahedron. The carboxylates of bpdc ligands alternately bridge the Fe(Ⅱ) cations to form 1D infinite helical chains. The Fe···Fe intrachain distance is 4.8246(6) . The adjacent chains are further interlinked by the coordination of bpdc ligands and hydrogen bonding to form a 3D framework. Magnetic studies for complex 1 show weak antiferromagnetic coupling between the Fe(Ⅱ) ions. The best-fit for χM T vs. T with a Hamiltonian∑∑==iBiiHJSi SigHS11 leadsto g = 2.314(4) and J = -0.68(1) cm-1.     

Syntheses and Crystal Structures of Two New Metal Phosphonates:[Mn(H_2O)_2(C_(12)H_8N_2)(HO_3PCH_2CH_2CO_2)] and [Co(H_2O)_4(C_(10)H_8N_2)]·(HO_3PCH_2CH_2CO_2)

By the reactions of manganese(II) acetate, 2-sulfoethylphosphonic acid, 1,10-phen (1,10-phen = 1, 10-phenanthroline) or cobalt(II) acetate, 4,4'-bipy and 2-carboxyethylphosphonic acid, two novel compounds of [Mn(H2O)2(C12H8N2)(HO3PCH2CH2CO2)] (1) and[Co(H2O)4 (C10H8N2)]· (HO3PCH2CH2CO2) (2) have been synthesized and characterized by IR spectroscopy, elemental analyses and single-crystal X-ray diffraction. Compound 1 has a 0D structure. Two Mn(II) ions are linked by two 2-carboxyethylphosphonic acid ligands, forming a centrosymmetric dimer. These dimers are further interlinked into a 2D layer structure by π-π stacking interactions and hydrogen bonds. Compound 2 has a 1D chain structure. The 2-carbo- xyethylphosphonic acid remains uncoor- dinated and acts as the organic template. By the bridge of 4,4'-bipy, the [Co(4,4'-bipy)]2+ chains are formed.     

Synthesis,crystal structures and luminescence properties of europium and terbium picolinamide complexes

The novel coordination structures of europium and terbium chloride-picolinamide complexes （EuCl3-（C6H6N2O）2.5H2O, Eu-pa and TbCl3.（C6H6N2O）2.5H2O, Tb-pa） are reported. The crystal structures in the solid state are characterized by X-ray single crystal diffraction, FTIR, Raman, FIR, THz and luminescence spectroscopy. In the crystal structures, the pyridyl nitrogen and carbonyl oxygen atoms in picolinamide are coordinated to the metal ions to form a five-membered ring structure. The experimental results indicate the similar coordination structures of Eu and Tb-pa complexes and the changes of hydrogen bonds and conformation provide models for the coordination structures of the ligands induced by complexation. The results of lanthanide ions with ligands having amide groups.     

DNA-binding Studies of Two Silver(I)-sulfonate Complexes Constructed by In Situ Reaction

Two silver(I)-sulfonate complexes,[Ag(NO_3)(4,4'-bipy)][Ag(HL)(4,4'-bipy)]·2H_2O(1) and[Ag(H_2O)(4,4'-bipy)][AgL(4,4'-bipy)]·2H_2O(2),have been synthesized by in situ reaction(H_2L = 2-formylbenzenesulfonic acid,4,4-bipy = 4,4-bipyridine).1 displays two parallel 1D chains expending to a 3D supramolecule by n—n interactions and O-H…O hydrogen bonds,in which the[Ag(NO_3)]or[Ag(HL)]units are joined by bridging 4,4'-bipy molecules,respectively.The interactions between the complexes and DNA were studied by means of fluorescence spectra and surface-enhanced Raman scattering(SERS) spectra.The special configuration and intercalation effects between 1 and DNA are stronger than that between 2 and DNA.