Takayoshi Kuroda-Sowa

Toward the Construction of Functional Solid-State Supramolecular Metal Complexes Containing Copper(I) And Silver(I)

Publisher Summary This chapter discusses construction of functional solid-state supramolecular metal complexes containing copper (I) and silver (I). The copper(I) and silver(I) ions are regarded as extremely soft acids favoring coordination to soft bases, such as ligands containing S and unsaturated N. Copper(I) and silver(I) complexes with these soft ligands give rise to an interesting array of stereochemistries and geometric configurations, with the coordination numbers of two to six all occurring. The most common stereochemistries for both ions are the linear two-coordinate and the tetrahedral four-coordinate geometries with some distortions of the environment, particularly in the presence of chelating type ligands, attributable to the spherical dl0 configuration. On the basis of resonance Raman spectra, the lowest excited state in the polymer is assigned to the Cu(I)-topyrazine metal-to-ligand charge-transfer excited state. Successful construction of multidimensional frameworks largely relies on ligand design to suit different geometries and coordination numbers of the metal ions.

Synthesis, crystal structures and magnetic behavior of polymeric lanthanide complexes with benzenehexacarboxylic acid (mellitic acid)

Abstract Three lanthanide complexes with mellitic acid [Ce2{C6(COO)6}(H2O)8]·H2O (1), [Eu2{C6(COO)6}(H2O)8]·H2O (2) and [Yb2{C6(COO)6}(H2O)10]·2H2O (3), have been synthesized and structurally characterized by X-ray crystallography and magnetic properties. The three compounds crystallize in the monoclinic space space P21/n, with unit cell dimensions of: a = 8.627(2), b = 13.218(2), c = 9.650(1) A , β = 95.93(1)° and Z = 2 for 1 ;a = 8.505(2), b = 13.145(1), c=9.536(2) A , β=94.73(2)° and Z=2 for 2 ; a = 8.420(1), b = 9.224(4), c = 16.229(1) A , β = 100.267(9)° and Z = 2 for 3. All three structures consist of an extended network of metal ions, coordinated to mellitate anions and water molecules linked by a complex hydrogen bonding. 1 and 2 are isomorphous with near isostructural [M2{C6(COO)6}(H2O)8] units in which the metal ion is coordinated by four water molecules and five oxygen atoms of the mellitate anions, and each mellitate group involves a tetrakis(bidentate) and bis(unidentate) coordination mode bridging six metal ions forming a three-dimensional framework. In 3 the ytterbium atom is bound with five water molecules and three oxygen atoms of the mellitate anion, and each mellitate moiety bridges four dodecahedral Yb(III) ions yielding a two-dimensional sheet structure. The magnetic susceptibility of 1 and 3 as a function of temperature (5.0–300 K) exhibits a sharp maximum at 6.0 K for both compounds.

An S⋯S contact assembled tetranuclear copper(I) complex with sulfur-rich ligand, 4,5-ethylenedithio-1,3-dithiole-2-thione

Abstract A copper(I) complex with 4,5-ethylenedithio-1,3-dithiole-2-thione (C 5 H 4 S 5 ), [Cu 4 I 4 (C 5 H 4 S 5 ) 4 ] ∞ , was synthesized and the molecular structure and packing were characterized crystallographically. The metal center is a stepped Cu 4 I 4 core coordinated by two ligands C 5 H 4 S 5 in different ways. One is bidentate coordinated through the thiocarbonyl group and the thioether group and the other is monodentate coordinated only through thiocarbonyl group. The Cu 4 I 4 clusters are bridged by bidentate C 5 H 4 S 5 molecules to form one-dimensional polymeric chains along the c -axis, and these chains form a three-dimensional network linked by interchain S⋯S contacts. The shortest S⋯S contact distance is 3.257 (2) A. A crystal of the complex is triclinic with space group P 1 , a=11.350(5) A , b=11.854(3) A , c=9.275(5) A , α=97.32(4)°, β=112.35(4)°, γ=67.67(2)°, V=1067.0(9) A 3 , Z=2, R=0.034, R w =0.051 .

Magnetic and Conducting Properties of New Halide-Bridged Mixed-Valence CuI−CuII 1D Coordination Polymers Including a Hexamethylene Dithiocarbamate Ligand

New mixed-valence Cu(I)-Cu(II) coordination polymers with one-dimensional, infinite-chain structures, [Cu(I)(2)Cu(II)X(2)(Hm-dtc)(2)(CH(3)CN)(2)](n) [Hm-dtc(-) = hexamethylene dithiocarbamate; X = Br(-) (1), I(-) (2)], have been prepared and structurally characterized by X-ray diffraction. These complexes consist of a mononuclear copper(II) unit Cu(II)(Hm-dtc)(2) and dinuclear copper(I) units Cu(I)(2)(CH(3)CN)(2)X(2). Magnetic studies have revealed that these complexes have a relatively strong antiferromagnetic interaction [J = -26.9 cm(-1) (1) and J = -22.2 cm(-1) (2)] between the unpaired electrons of the Cu(II) ions through the dinuclear copper(I) halide unit of Cu(I)(2)X(2) in the chain. The electrical properties of 1 and 2 are investigated using an impedance spectroscopy technique, and it is revealed that these complexes exhibit intriguing semiconducting properties with small activation energies [E(a) = 0.562 eV (1) and E(a) = 0.479 eV (2)].

Syntheses, structures and properties of copper(I) co-ordination polymers with bridging phenazine: construction of one- and two-dimensional structures with π–π stacking of phenazine

Four novel copper(I) phenazine (phz) compounds, [{Cu(phz)(NO3)}∞]1, [{Cu(acr)2(NO3)}2(phz)(H2O)]2(acr = acridine), [{Cu2(phz)(PFO3)}∞]3 and [{[Cu(phz)(MeCN)]2(C16H10)(PF6)2}∞]4(C16H10= pyrene) have been synthesized and their molecular structures and packing have been determined by single-crystal X-ray diffraction methods. The copper atoms in 1 are bridged by phz forming an infinite one-dimensional zigzag chain. These bridging phz molecules have a π–π interaction between neighbouring chains forming an infinite columnar stack of phz molecules. The monomer complex, 2, has an infinite columnar stack of metal-free phz and metal-co-ordinated acr. Copper(I) atoms in 3 are bridged by phz and PFO32– alternately. The resulting one-dimensional chains are connected through a tetradentate, asymmetric PFO32– bridge, with π–π interaction between the phz molecules forming an infinite two-dimensional sheet structure. The backbone of compound 4 is almost the same as in 1 except that a pyrene molecule is intercalated into every other phz stack in a one-dimensional chain. The electrical conductivity of compound 3 and [{[Cu(phz)(MeCN)]2(C16H10)(PF6)2I1.3}∞]5, obtained by iodine doping of compound 4 were 1 × 10–7.6 and 1 × 10–4.7 S cm–1, respectively. The electronic absorption bands of compounds 1, 3 and 4 which appeared around 700 nm are characteristic of copper(I) co-ordination polymers with bridging phz.

Crystal structure and magnetic properties of manganese (II) mellitate, [Mn2{C6(COO)6}(H2O)6][Mn(H2O)6]·2H2O with two-dimensional layered structure and three-dimensional hydrogen bonding networks

Abstract The crystal and molecular structure of manganese (II) mellitate, [Mn2{C6(COO)6}(H2O)6][Mn(H2O)6]·2H2O, has been determined by X-ray structure analysis. The complex crystallizes in the monoclinic system, space group C2/c, with cell constants a = 23.298(3), b = 6.456(3), c = 17.072(2) A , β = 101.01(1)° and Z = 4 . The structure was solved and refined to R = 0.029 (Rw = 0.036). There are two types of manganese ions in the structure. Mn(1) is situated on a crystallographic center of symmetry and bound to six water molecules while Mn(2) is coordinated octahedrally by three water molecules and three carboxylate oxygen atoms. The major structure feature is that the polyanion formed by Mn(2) ions and the mellitate hexanions with composition of [Mn2{C6(COO)6}(H2O)6]n2n− possesses a two-dimensional layered structure which is linked through a complex three-dimensional hydrogen bonding associated with the Mn(1) cation [Mn(H2O)6]2+ and the water of crystallization. Analysis of variable-temperature magnetic susceptibility data (5.0–300 K) shows that the complex displays antiferromagnetic exchange.

SYNTHESIS AND STRUCTURE OF A THREE-DIMENSIONAL LANTHANUM(III) COORDINATION POLYMER WITH MELLITATE, {La2[C6(COO)6](H2O)9} · 2H2O

Abstract The crystal and molecular structure of a lanthanum(III) mellitate, La2C12H22O23, has been determined by X-ray structural analysis using a combination of direct and heavy atom methods. The complex crystallizes in the monoclinic space group P21/n with unit-cell dimensions of a = 6.723(4), b = 11.368(5), c = 29.813(4) A and β = 95.851(3)°. Block-diagonal least-squares refinement using automated diffractometer-collected data resulted in R = 2.5 and Rw = 3.4. The crystal structure consists of layers perpendicular to the a axis. Each layer is formed by an extended network of lanthanum ions coordinated with mellitate anions and water molecules, and linked through a complex three-dimensional hydrogen-bonding network. Among the six carboxylate groups of the mellitate anion, five form coordination bonds to six lanthanum atoms. The two independent lanthanum ions are both nine-coordinate and the configuration around lanthanum is a tricapped trigonal prism with the La-O bond distances ranging from 2.457 A to ...

A UNIQUE COORDINATION POLYMER CONSISTING OF TWO PARALLEL C5H4S5 MOLECULES BRIDGING TWO SILVER(I) IONS (C5H4S5=4,5-ETHYLENEDITHIO-1,3-DITHIOLE-2-THIONE )

The silver(I) complex with 4,5-ethylenedithio-1,3-dithiole-2-thione (C 5 H 4 S 5 ), [Ag(C 5 H 4 S 5 ) 2 NO 3 ] ∞ , was synthesized and the molecular structure and packing were characterized crystallographically. The Ag atom is coordinated with four ligands through two thiocarbonyl sulfur atoms (CS) and two thioether sulfur atoms of the six-membered ring (–S–), respectively, forming an extremely distorted tetrahedral geometry. This is the first metal complex of TTF or BEDT–TTF analogs, in which the sulfur atom in a five- or six-membered ring directly coordinates to the silver(I) ion. Two parallel C 5 H 4 S 5 molecules are connected by two Ag(I) ions to give a unique infinite chain. The S⋯S contacts of 3.41 A are very strong between two nearby chains along the b axis, generating a two-dimensional network. The crystal of the complex is monoclinic with space group P 2/ n , a =8.701(1), b =8.955(1), c =11.811(1) A, β =91.438(8)°, V =920.0 A 3 , Z =2, R =0.031, R w =0.045. Although the iodine-doped free ligand is an insulator, the iodine-doped complex is a semiconductor ( σ =3×10 −5 S cm −1 ) at room temperature.

Structure and 1H NMR study of copper(I) complex with ethylene and tetramethylethylenediamine

Abstract A ternary copper(I) complex with ethylene and tetramethylethylenediamine(tmen) has been prepared and the structure characterized by the single crystal X-ray method. The copper atom is coordinated to two nitrogen atoms of tmen and an ethylene molecule in a trigonal-planar arrangement. The CC bond distance of 1.36(1) A is slightly longer than that of the free ethylene (1.335 A). In the 1 H NMR study, chemical shifts of ethylene protons at 5.46 ppm move upfield (4.16 ppm) upon coordination to copper(I). This indicate that the π back donation from copper to the ethylene is rather weak compared with other metal-ethylene systems.

Silver(I) complexes of triazine derivatives having stepped π–π interactions and 2D sheets

Abstract Reactions of silver(I) perchlorate and triflate with the triazine ligands 2,4,6-trimethoxy-1,3,5-triazine (L1) and 2,4,6-triphenyl-1,3,5-triazine (L2) have provided three novel silver complexes: [Ag(L1)2](ClO4) (1), [Ag(L1)2](CF3SO3) (2) and [Ag2(L2)(CF3SO3)2] (3). The crystal structures of these complexes have been determined by single-crystal X-ray diffraction. Each complex exhibits distinct coordination behavior and different frameworks. Complex 1 has a 1D stepped framework in which one crystallographically independent metal center interacts with two L1 molecules and strong π–π interactions between the triazine planes of two L1 molecules exist. On the other hand, complex 2 has a herringbone-like molecular packing in which the triflate ions are arranged between mononuclear complex cations. In complex 3, L2 molecules are suspended between two double chains of silver triflate through the coordination to silver(I) ions to form the 2D sheet network structure. The factors that influence the crystal structure and packing are discussed.