Search

The new title two-dimensional hetero-tetra nuclear Cu 3 –Na coordination polymer {[NaCu 3 Cl(cpiap) 2 (H 2 O) 3 n ·6nH 2 O} (1) consists of crystallographically two-independent copper(II) centers, each bridged by a sodium cation through carboxylate-oxygen of the deprotonated H 3 cpiap ligand (H 3 cpiap = 2-(carboxyphenyl)iminoaceticpropanoic acid) to CuII (2) and CuII (2−) cations, and through water molecules to CuII (1) cation. CuII (2) and CuII (1) cations are bridged by carboxylate-oxygen atoms of the ligand in a syn-anti mode which, alternate regularly within the chain being bridged by a tetra coordinated sodium cation. Each CuII (2) and CuII (2−) cation in (1) is in an octahedral environment formed by four carboxylate-oxygens from two cpiap3− ligands, one nitrogen atom and a bridging chloride atom. CuII (1) cation is in a square pyramidal environment formed by three water molecules and two carboxylate-oxygens from two cpiap3− ligands. The ligand acts simultaneously as monodentate and tridentate toward CuII (1) and CuII (2) cations respectively. The lattice water molecules involved in O H···O hydrogen bonding are situated in the void spaces between layers. The zigzag chains, which run along the b-axes further construct three-dimensional metal-organic framework via hydrogen bonding and weak face-to-face π-π interactions. Weak C H···O interactions are also present. [ABSTRACT FROM AUTHOR]

The title compound, N-(2-pyridylmethyl)-L-alanine) zinc(II), [Zn(C10H11N3O2S)], a coordination polymer derived from the mixed ligands, N-(2-pyridylmethyl)-L-alanine (HL1) and ammonium thiocyanide (L2) has been synthesized and characterized by IR spectroscopy, 1H-NMR, elemental analysis, thermogravimetric analysis and single crystal x-ray structure determination. The single crystal X-ray structure analysis of the title compoundreveals a molecular polymeric compound that crystallizes in the orthorhombic crystal system and P2(1)2(1)2(1) space group. The ligand acts as a bridge between adjacent zinc(II) centres, each of which adopts a five-coordinate geometry. Zinc bonds to two N atoms and one O atom of HL1, one N atom of L2 and one O atom of another HL1 ligand. This is confirmed by IR spectroscopy. Thermogravimetric analysis shows a one-step decomposition of the complex to leave a zinc sulfide residue. [ABSTRACT FROM AUTHOR]

C8H10N2O2, orthorhombic, Pbca (no. 61), a = 11.0571(2) Å, b = 8.1172(2) Å, c = 17.6080(4) Å, V = 1580.37(6) Å3, Z = 8, Rgt(F) = 0.0324, wRref(F2) = 0.0872, T = 100(2) K. [ABSTRACT FROM AUTHOR]

C8H10N2O2, orthorhombic, Pbca (no. 61), a = 11.0571(2) Å, b = 8.1172(2) Å, c = 17.6080(4) Å, V = 1580.37(6) Å3, Z = 8, Rgt(F) = 0.0324, wRref(F2) = 0.0872, T = 100(2) K. [ABSTRACT FROM AUTHOR]

Trimethyl citrate, C9H14O7 (systematic name: trimethyl 2-hydroxypropane-1,2,3-tricarboxylate), 2, was prepared by the esterification of citric acid and methanol in the presence of thionyl chloride at 273 K. The bond lengths and angles in 2 compare closely with those observed in citric acid. The C--C bonds adjacent to the terminal carboxyl groups are significantly shorter than those around the central C atom. The central carboxylate group and the hydroxy group occur in the normal planar arrangement with an r.m.s. deviation of 0.0171 Å from the mean plane involving all six atoms in the central unit. The crystal structure is almost completely dominated by the formation of inversion dimers through an O--H...O hydrogen bond, together with an extensive array of weaker C-- H...O contacts. These generate a three-dimensional network structure with molecules stacked along the c-axis direction. [ABSTRACT FROM AUTHOR]

The ordered structure of the guest-free microporous metal-organic framework zinc 5-tert-butyl isophthalate {Zn[(CH3)3CC6H3(CO2)2]} has been determined and shown to be easily loaded with methanol to form {Zn[(CH3)3CC6H3(CO2)2]}·CH3OH. The methanol forms a S6-symmetric hexamer within the pores of the material that is uniquely defined by the void space and exerts a subtle structural effect on the framework structure of the host. The work demonstrates the use of this type of metal-organic framework as a matrix to isolate unique molecular clusters in a facile manner. [ABSTRACT FROM AUTHOR]

Reaction of indole with the combination 1-cyclohexyl-2-pyrrolidinone and phosphoric trichloride gives the hydrochloride of 3-(1-cyclohexylpyrrolidin-2-ylidene)-3H-indole. Treatment of this with base at room temperature causes hydrolytic ring opening producing 4- (cyclohexylamino)-1-(1H-indol-3-yl)butan-1-one but careful low-temperature basification allows the isolation of 3-(1-cyclohexylpyrrolidin-2-ylidene)-3H-indole itself. The crystal structure of the hydrochloride, as a dihydrate, was determined. [ABSTRACT FROM AUTHOR]

Cadmium dithiocarbamato complexes of piperidine ( 1 ) and tetrahydroquinoline ( 2 ) were synthesized and characterized by elemental analysis, FT-IR spectroscopy, NMR and TGA analyses. The X-ray single crystal structure of bis (piperidinedithiocarbamato)cadmium(II) complex ( 1 ) was determined. The synthesized compounds were used as single source precursors to deposit CdS films on glass substrates at 350, 400 and 450 °C using the aerosol assisted chemical vapor deposition (AACVD) method. The surface morphology and the size of the CdS films were determined by AFM and SEM analyses; the crystalline phases by p -XRD analyses and the elemental composition by EDX measurements. The particle sizes were found to be in the range between 50–110 nm and 100–220 nm for complex ( 1 ) and ( 2 ), respectively. The electronic properties of the CdS films were analyzed by UV–Vis and Raman spectroscopic methods. Results revealed that the morphology, size and composition of the films are influenced by the deposition temperature. [ABSTRACT FROM AUTHOR]

Bis ( O -alkylxanthato)nickel(II) complexes (alkyl=hexyl and octyl) have been synthesised and their X-ray single crystal structures determined. Nickel sulfide thin films were deposited from both complexes at different deposition temperatures by the aerosol assisted chemical vapour deposition (AACVD) method. Phase pure rhombohedral NiS and mixture of rhombohedral NiS (millerites) and Ni 17 S 18 were deposited onto the glass and silicon substrates at temperatures between 250 and 400 °C. SEM images show that the films are based on irregular grains, nanodendrites and feather like morphologies. [ABSTRACT FROM AUTHOR]

Four new complex salts [Ru11Cl(Tpm)(LA)2]- [PF6]n [Tpm = tris(l-pyrazolyl)methane; n - 1, LA = pyridine (py) 1 or ethyl isonicotinate (EIN) 2; n = 3, LA = N-methyl- 4,4'-bipyridinium (MeQ+) 3 or N-phenyl-4,4'-bipyridinium (PhQ+) 4] have been prepared and characterized. Electronic absorption spectra show intense d → μ* metal-to-ligand charge-transfer (MLCT) absorption bands, while cyclic voltammetry reveals a reversible RuIII/II wave, accompanied by quasireversible or irreversible LA based reductions for all except 1. Single crystal X-ray structures have been obtained for l•Me2CO, 2, and 3•Me2CO. For 2--4, molecular first hyperpolarizabilities ß have been measured in acetonitrile solutions via the hyper-Rayleigh scattering (HRS) technique at 800 nm. Stark (electroabsorption) spectroscopic studies on the MLCT bands in frozen butyronitrile allow the indirect estimation of static first hyperpolarizabilities ß0. The various physical data obtained for 3 and 4 are compared with those reported previously for related cis-{Ru11(NH3)4}2+ species [Coe, B. J. et al. J. Am. Chem. Soc. 2005, 127, 4845]. TD-DFT calculations on the complexes in 1--4 confirm that their lowest energy absorption bands are primarily Ru11 --> LA MLCT in character, while Ru11 → Tpm MLCT transitions are predicted at higher energies. DFT agrees with the Stark, but not the HRS measurements, in showing that ß0 increases with the electron-accepting strength of LA. The 2D nature of the chromophores is evidenced by dominant ßxxy tensor components. [ABSTRACT FROM AUTHOR]

Abstract: Cobalt(II) complexes of sulfadiazine formulated as [Co(C10H9N4O2S)2(CH3OH)2] and [Co(C10H9N4S)2(H2O)2] have been synthesized and characterized by elemental analysis, infrared and UV–Vis spectroscopy and magnetic susceptibility measurements. The crystal structures of the complex [Co(C10H9N4O2S)2(CH3OH)2] and of free sulfadiazine are also reported. The cobalt complex and the sulfadiazine ligand both crystallize in the monoclinic space group, P21/c, with sulfadiazine acting as a bidentate ligand. Cobalt is coordinated to two-sulfonamide nitrogen and the pyrimidine nitrogen of the sulfadiazine. Two molecules of methanol complete the octahedral geometry around the cobalt, with interligand hydrogen bonding between methanol and sulfadiazine. Infrared spectroscopy confirmed the presence of water molecule in the coordination sphere of [Co(C10H9N4S)2(H2O)2]. The electronic spectra and magnetic moments of both complexes were similar, indicating that both complexes have similar structure. [Copyright &y& Elsevier]

PbSe nanowires (NWs) have been synthesized by using a single-source precursor route. Carefully controlling the conditions of individual reactions leads to PbSe NWs with well-defined diameters (8-25 nm) and lengths (100 nm-1 μm). The as-grown PbSe NWs are highly crystalline, defect free, and readily dispersible in organic solvents. The NWs have been characterized by X-ray diffraction and high-resolution transmission electron microscopy. [ABSTRACT FROM AUTHOR]