Crystal structure and magnetic properties of two bimetallic chain compounds

Two bimetallic magnetic chain compounds of {[Mn(dpop)(H₂O)][Mn(dpop)][Fe[CN]₆]•8.5H₂O•0.5DMSO} _n ( 1 ) and {[Mn(dpop)][Ni[CN]₄]} _n ( 2 ) (dpop = 2,13-dimethyl-3,6,9,12,18-pentaazabicyclo-[12.3.1]-octadeca-1(18),2,12,14,16-pentaene) have been synthesized and characterized by single-crystal X-ray diffraction and magnetic measurements. Both complexes have cyano-bridged chain structures, in which complex 1 is a zigzag chain, while complex 2 is nearly a straight line. The magnetic susceptibility results indicate that there is a weak ferromagnetic interaction between manganese (II) ions in complex 1 , whereas the interaction is antiferromagnetic in complex 2 .     

Fullerene compounds with transition metals MnC60: Preparation, structure, and properties

This review summarizes the results of studies on complexation of fullerene C₆₀ with transition metals. The structural background for metal-fullerene interaction is discussed. Much attention is focused on the compounds M_nC₆₀. Methods of their preparation, structure, and properties are considered in detail. The nature of their catalytic activity is discussed. Translated from Zhumal Struktumoi Khimii, Vol. 41, No. I, pp. 164-181, January–February, 2000.     

Microwave synthesis,structure, and properties of molybdophosphate compounds

Two compounds of disphosphopentamolybdate(VI) with the formulae (C₄H₁₄N₂O)₃- [P₂Mo₅O₂₃]?·?3H₂O (1) and (C₄H₁₄N₂O)₅(NH₄)₂[P₂Mo₅O₂₃]₂?·?5H₂O (2) have been synthesized by a simple, fast and efficient microwave method, and their crystal structures and spectroscopic properties have been studied. The heteropoly anion [P₂Mo₅O₂₃]^6? has a known structure built of five MoO₆ octahedra and two PO₄ tetrahedra. The MoO₆ octahedra form a pentagonal ring by sharing four edges and one corner and the PO₄ tetrahedra are attached to one side of the ring by three oxygen atoms. The most interesting feature of compound 1 is its extensive framework based on a one-dimensional zigzag chain. In compound 2, a more extensive and complicated framework of hydrogen bonds joins the anions, organic cations and water molecules together.     

Epoxyallyl polymers: Preparation,structure, and properties

Ways to prepare epoxyallyl polymers with a structure of interpenetrating networks (IPNs) were considered. It was shown that the constructability and high adhesive and cohesive characteristics of obtained polymers evoke interest in the practicality of curing and structuring study for epoxyallyl IPNs and the properties of materials based on them.     

Synthesis, structure and properties of pyrazole type tetrakis compounds

A series of pyrazole type tetrakis compounds has been synthesized by reaction of aromatic or heterocyclic dialdehydes and pyrazolone derivatives. Structure and tautomerism of the products were investigated by spectroscopic methods and X-ray analysis. Several tetrakis compounds form inclusion complexes with solvents like alcohols, ethers, and ketones in a definite ratio via hydrogen bonds.     

Preparation, structure and properties of PP-g-AA grafting copolymer

Polypropylene grafting with AA was prepared by reactive extrusion with pre-irradiated PP (rPP) as the homogeneous initiator. The effects of the pre-irradiated dose, the fraction of rPP and the concentration of acrylic acid on the grafting reaction were studied and the grafted PP was characterized by Fourier transition infrared spectroscopy (FTIR), differential scanning calorimeter (DSC) and polarized light microscopy (PLM). The results show that the degradation of PP was suppressed efficiently with this novel method for preparing PP-g-AA copolymers, and the grafted copolymers with good mechanical properties were obtained. It was found that the product with higher graft degree (G _d)(0.19%) and relatively excellent mechanical properties can be produced if the mass ratio of PP/rPP/AA is 90:10:0.8, where the selected pre-irradiation dose of rPP is 4 kGy. Moreover, an adhesive strength of 4.88 kN/m was reached in the PP-g-AA/aluminum laminate. __________ Translated from Chinese Journal of Applied Chemistry, 2007, 24(7): 737–741 [译自: 应用化学]     

Bis(di-tert-butylphosphinito-P)mercury. Preparation and properties

[(t-C₄H₉)₂P(O)]₂Hg (1), containing mercury-phosphorus bonds, was prepared from the phosphine oxide and Hg(OAc)₂. 1 reacts with X₂ (X  Br, I) to form (t-C₄H₉)₂P(O)X and with HgX₂ (X  Cl, Br, I, SCN, CN, C₆H₅ and OAc) yielding the mixed mercury compounds (t-C₄H₉)₂P(O)HgX. The new compounds were characterized by ¹H, ¹³C, ³¹P and ¹⁹⁹Hg NMR and MS.     

Allyl strontium compounds: synthesis, molecular structure and properties

The synthesis and attempted isolation of neutral bis(allyl)strontium [Sr(C(3)H(5))(2)] (1) resulted in the isolation of potassium tris(allyl)strontiate K[Sr(C(3)H(5))(3)] (2). In situ generated 1 shows a pronounced Br?nsted basicity, inducing polymerisation of THF. Ate complex 2 crystallises as [K(THF)(2){Sr(C(3)H(5))(3)}(THF)](∞) (2·(THF)(3)). The salt-like solid state structure of 2·(THF)(3) comprises a two-dimensional network of (μ(2)-η(3):η(3)-C(3)H(5))(-) bridged potassium and strontium centres. Synthesis of allyl complexes 1 and 2 utilised SrI(2), [Sr(TMDS)(2)] (3) (TMDS = tetramethyldisilazanide), and [Sr(HMDS)(2)] (HMDS = hexamethyldisilazanide) as strontium precursors. The solid state structure of previously reported [Sr(TMDS)(2)] (3) was established by X-ray single crystal analysis as a dissymmetric dimer of [Sr(2)(TMDS)(4)(THF)(3)] (3·(THF)(3)) with multiple Si-HSr agostic interactions. The presence of ether ligands (THF, 18-crown-6) influenced the Si-HSr resonances in the NMR spectra of the amido complex 3.     

Synthesis,crystal structure,and fluorescence properties of several schiff-base compounds

Two new Schiff-base compounds, 1,6-bis(4-dimethylaminobenzyl)-2,5-diaza-1,5-hexadiene (bdh), 1,4-bis(4-dimethylaminobenzyl)-2,3-diaza-1,3-butadiene (bdb), and a silver complex of the latter ([Ag₂(bdb)₃(NO₃)₂]·H₂O, 1) have been synthesized and characterized. The crystal structure of complex 1 was determined. 1 is a dinuclear complex, with the silver ions lying in coordination tetrahedra formed by two nitrogen atoms from the bdb ligands and two oxygen atoms from the nitrate anions. The fluorescence properties of bdh and bdb were studied; the fluorescence of bdb was quenched by the addition of silver ions, indicating that it is a potential fluorescent reagent for the analysis of silver.     

The structure and properties of carbonyl compounds

The (planar) minimum energy configurations of cis and trans glyoxal, and of parabenzoquinone, have been determined using the MINDO/2 method. Good agreement with the experimental structures is obtained. Other molecular properties for these systems are reported.     

Preparation and structure of alkali metal intercalation compounds

The preparation methods of intercalation compounds fall into four main groups: use of alkali metal solutions in liquid ammonia, organometallic reagents, electrochemical methods, and solid state processes. Each of these will be briefly described and a general comparison of the advantages and disadvantages will be made. Structural problems concern the positions occupied by the guest ions and their mobility from one site to one another in the host structure. The resulting ionic conductivity of the intercalation compounds depends on factors such as the ratio between available and occupied sites in the van der Waals gap, the ionicity of the bonds in the host structure, the site geometry, and the nature of the alkali metal.     

Synthesis,structure and nonlinear optical properties of three dimensional compounds

The combination of metal ions with H₃tbba has resulted in the formation of two three dimensional coordination compounds {[Zn(H₂tbba)₂(H₂O)] · 2(OC₃H₆)} _n (1) and {[Mn(H₂tbba)₂(H₂O)] · 2(OC₃H₆)} _n (2) (H₂tbba = 2-thiobarbituric acid anion). Compounds 1 and 2 are isostructural with metal ions bridged by four hydroxyl oxygens from four different H₂tbba ligands to form a 3D network. H₂tbba exhibits bidentate coordination with both hydroxyl oxygens participating in coordination, a new coordination mode. Nonlinear absorption and refraction of 1 and 2 in DMF are studied by using Z-scan measurement technique at 532 nm. 1 and 2 possess nonlinear optical absorption and self-focusing.     

Synthesis, structure and properties of intercalation compounds containing perfluoroalkyl groups

Synthesis, structure and properties of various layered materials containing perfluoroalkyl groups in their interlayer space were summarized. They were obtained by ion exchange method for layered materials with ion exchange capacity and by silylation technique for those possessing acidic hydroxyl groups. The orientation of perfluoroalkyl groups greatly changed depending on their contents in the layered materials. The nature of the interlayer space of them changed from hydrophilic to hydrophobic and they were well dispersed in appropriate organic solvents. Some of them formed so called nanosheet solution and film samples were prepared from it. Organic molecules were introduced into the intercalation compounds by co-adsorption or exfoliation-restacking methods. The empty space surrounded by perfluoroalky chains where organic molecules are included showed unique properties. The weak interaction between perfluoroalkyl chains and included organic molecules lead the easy diffusion of them in the interlayer space, which caused the aggregation of them or affected the distribution of isomers obtained by photochemical reaction. The low vibrational C-F bonding in perfluoroalky groups reduced radiational quenching, accordingly enhanced the fluorescence from included organic dyes.     

Preparation, structures, and photocatalytic properties of three new uranyl-organic assembly compounds

Three new uranyl-organic coordination polymers (UO2)8(NDC)12(4,4'-bipyH2)3(4,4'-bipyH)3 (1), (UO2)3O[Ag(2,2'-bipy)2]2(NDC)3 (2), and (UO2)2(NDC)2(2,2'-bipy)2 (3), where NDC=1,4-naphthalenedicarboxylate and bipy=bipyridine, have been prepared in hydrothermal conditions. Both 1 and 2 possess a 2D structure while 3 is composed of 1D zigzag chains. In 1 there are mononuclear pentagonal-bipyramidal U-O polyhedra and 1D channels filled with 4,4'-bipy molecules, whereas in 2 there are mononuclear hexagonal-bipyramidal U-O polyhedra and tetranuclear pentagonal-bipyramidal U-O clusters which form 2D channels with occluded [Ag(2,2'-bipy)2]+ counterions. In 3 both the NDC and the bipy ligands coordinate to uranyl centers, leading to hexagonal-bipyramidal polyhedra which are connected to form 1D zigzag chains. Under UV or visible irradiation, 1 and 2 degrade rhodamine B with similar efficiency. The correlation between photocatalytic reaction rate and oxygen concentration for 1 and 2 has also been elucidated. Crystal data: 1, triclinic, space group P1, a=11.037(2) A, b=15.126(3) A, c=15.660(3) A, alpha=62.05(3) degrees, beta=72.26(3) degrees, gamma=82.05(3) degrees, and Z=2; 2, triclinic, space group P1, a=14.161(3) A, b=15.122(3) A, c=18.212(4) A, alpha=85.73(3) degrees, beta=76.99(3) degrees, gamma=67.32(3) degrees, and Z=2; 3, monoclinic, space group P2(1)/n, a=10.7976(18) A, b=31.501(6) A, c=11.590(2) A, beta=97.609(4) degrees, and Z=4.     

Preparation, structure, and unique redox properties of mono-, bis-, and Tris(diarylmethylene)-1,3,5-trithianes and related compounds

A series of 1,3,5-trithianes 1-3 having diarylmethylene units were designed as novel electron donors giving highly colored cationic species upon oxidation. They were prepared along with the dithiane and dithiazine derivatives 4-6 by the reactions of lithiated heterocycles with diaryl ketones followed by dehydration. Voltammetric analyses indicate that a large structural change and/or transannular bonding are induced during their electrochemical oxidation. Mono(diarylmethylene) derivative 1a exhibits electrochromism with vivid change in color from faintly yellow to deep blue with concomitant rotation around the exocyclic bond. Both of the strongly colored salts obtained upon oxidation of 2,4-bis- and 2,4,6-tris(diarylmethylene)-1,3,5-trithianes (2aa and 3) consist of the dications with a 1,2,4-trithiane ring, suggesting the easy skeletal rearrangement of the transannular dications with a trithiabicylo[3.1.0]hexane ring. Upon reduction of these salts were obtained bright yellow 12 and 13, respectively, with high electron-donating properties due to the tetraarylbutadiene-type conjugation, thus giving another class of electrochromic compounds.     

Preparation and properties of cyclodextrin-metal carbonyl inclusion compounds

One-to-one inclusion compounds were obtained in a crystalline state in high yields by treatment if ironpentacarbonyl and dimanganesedecacarbonyl with γ-cyclodextrin. These represent the first examples of cyclodextrin inclusion compounds with binary metal carbonyl complexes; the metal carbonyl complexes included in cyclodextrins are thermally more stable than the free complexes.     

1-Phenylvinyl compounds of lithium,mercury, and thallium

Summary Methods are described for the preparation of 1-phenylvinyl compounds of mercury and thallium from the salts of these metals and 1-phenylvinyllithium. Some chemical properties of these compounds were investigated.