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The synthesis of five new complexes involving the ephedrinedithiocarbamate ligand (ephedtc) with group 13 and 15 metals (III) is reported. Complexes [As(ephedtc) 3 ] ( 1 ), [Sb(ephedtc) 3 ] ( 2 ), [Bi(ephedtc) 3 ] ( 3 ), and [In(ephedtc) 3 ] ( 5) were obtained from the ephedrinedithiocarbamate sodium salt [Na(ephedtc)] and the corresponding trichlorides MCl 3 , whereas for [Ga(ephedtc) 3 ], ( 4 ) Ga(NO 3 ) 3 was used. All compounds were characterized by elemental analyses, IR, mass spectrometry (FAB + ) and 1 H and 13 C NMR. In addition, single crystal structures of 2 and 5 were obtained showing two different coordination modes for the dithiocarbamate moiety, an anisobidentate coordination mode for 2 and an isobidentate coordination for 5 that generates a propeller-type structure. Compound 2 shows a distorted trigonal antiprismatic geometry around the metal atom while in 5 a distorted octahedral geometry is observed. Additionally, the crystalline structure of the ionic pair [ephedrinium] [ephedrinedithiocarbamate] ( 6 ) was determined. Antibacterial assay showed that 5 was the most active against ATCC bacterial strains and clinical isolate E. coli BLE (MIC 14.6–29.9 µM), and 3 against MRS strains (MIC 1.7 and 13.4 µM). The chemical hardness concept and the location of the HOMO and LUMO frontier orbitals on the molecular structures of 1 – 5 were employed to explain its particular antibacterial activity, using the DFT calculations.

The syntheses and characterization of six new triorganotin(IV) complexes, Ph3Sn(PrACDA) (1), Bu3Sn(PrACDA) (2), Ph3Sn(BzACDA) (3), Bu3Sn(BzACDA) (4), Me3Sn(BzACDA) (5) and Cy3Sn(BzACDA) (6) (ACDA = 2-amino-1-cyclopentene-1-carbodithioate anion) are reported. Compounds 1–6 were synthesized by the reaction between the sodium salts of 2-N-propyl- or 2-N-benzyl-2-amino-1-cyclopentene-1-carbodithioate and R3SnCl (R = Ph, Bu, Me, Cy) in a 1:1 M ratio. The complexes were characterized by elemental analyses, IR and NMR (1H, 13C and 119Sn) spectroscopy and by FAB+ mass spectrometry. The experimental data reveal that the tin atom is coordinated to the ligand by means of the two sulfur atoms from the carbodithioate group in an anisobidentate mode, while the 119Sn{1H} NMR spectra suggest a pentacoordinate metal center in 1–4 and a tetracoordinate tin atom for 5 and 6. The molecular structures of complexes 1, 3 and 5 were confirmed by single crystal X-ray diffraction analysis showing the presence of N–H···S hydrogen bonding and a distorted trigonal bipyramid geometry for the tin atoms.

Four new bismuth(III) complexes; (CH2S)2Bi[S2CN(CH2)4] (2), CH2(CH2S)2Bi[S2CN(CH2)4] (3), S(CH2CH2S)2Bi[S2CN(CH2)4] (4), O(CH2CH2S)2Bi[S2CN(CH2)4] (5) were prepared from the reaction of the sodium salt of pyrrolidine-dithiocarbamate (1) with four chloro-dithia-bismuth(III) compounds containing five-, six- and eight-membered heterocycles. The complexes were characterized by elemental analyses, infrared, and 1H and 13C NMR spectroscopy. In addition, the single crystal X-ray structures of 2–4 were obtained, showing an asymmetric bidentate coordination mode of the dithiocarbamate ligand moiety. The metal center in 2 and 3 is tetracoordinated, while in 4 a pentacoordinate metal center is observed, the latter is achieved through the 1,5-transannular Bi⋯S interaction, which is common in these types of metallocane rings. Antibacterial assays showed that 2–5 were active in ATCC and clinical isolated strains. Antiploliferation assays were carried out showing high antiproliferative effect against breast cancer cell lines, in vitro. A QSAR model employing quantum global and local chemical descriptors was constructed to gain further insight into their antibacterial activity.

Six new diorganotin (IV) complexes, [Ph2Sn(Pr-ACDA)2] 1, [Bu2Sn(Pr-ACDA)2] 2, [Ph2Sn(Bz-ACDA)2] 3, [Bu2Sn(Bz-ACDA)2] 4, [Me2Sn(Bz-ACDA)2] 5, [t-Bu2Sn(Bz-ACDA)2] 6 are reported (where ACDA is the 2-amino-1-cyclopentene-1-carbodithioic anion). The diorganotin complexes were prepared from reactions between sodium N-propyl and N-benzyl-2-amino-1-cyclopentene-1-carbodithioate with R2SnCl2 (R=Ph, Bu, Me, tBu) in a 2:1 ratio. All complexes were characterized by elemental analysis, IR, multinuclear NMR (1H, 13C, and 119Sn), FAB+ mass spectrometry and in the case of 2, 3 and 5 by single-crystal X-ray diffraction. Both solution and solid state studies show that dithioacid ligands are coordinated to tin in an aniso-bidentate manner. In all complexes coordination takes place only through the carbodithioate moieties. 119Sn NMR data indicate pentacoordination of tin in solution. The tin coordination geometry, in all three structures is a highly distorted octahedral geometry, where tin is bonded to the four sulfur atoms of the two aniso-bidentate carbodithioate ligands in the equatorial plane and the organic substituents on tin atom in trans-positions. In addition, the crystal structures show the presence of N-H…S hydrogen bonding contacts.

The possibility of using less expensive and nontoxic metals, such as copper, as substitutes for more expensive heavy metals in the synthesis of new transition-metal complexes to be used as sensitizers in dye-sensitized solar cells (DSSCs) has stimulated research in this field. The novel photoluminescent copper(I) complex bis(triphenylphosphane-κP)[trans-(±)-2,4,5-tris(pyridin-2-yl)-2-imidazoline-κ2 N 2,N 3]copper(I) hexafluorophosphate, [CuI(C18H15N5)(C18H15P)2]PF6, has been successfully synthesized and characterized by IR and 1H NMR spectroscopy, as well as by single-crystal X-ray diffraction and thermogravimetric analysis. The complex showed interesting photophysical properties, which were studied experimentally in solution and in the solid state by UV–Vis and fluorescence spectroscopy. Density functional theory (DFT) calculations with dichloromethane as solvent reproduced reasonably well the HOMO and LUMO orbitals of the title compound.

Five new chlorodiorganotin(IV) complexes derived from dithiocarbamate ligands have been prepared and structurally characterized. The complexes 1–5 with the general formula {(Ph2SnCl)dtc} (dtc = R1R2NCS2−; 1, R1 = Bn, R2 = 9-anthrylmethyl; 2, R1 = Bn, R2 = 9-phenanthrylmethyl; 3, R1 = Bn, R2 = 1-pyrenylmethyl; 4, R1 = 1-naphthylmethyl, R2 = 1-pyrenylmethyl; 5, R1 = R2 = 1-pyrenylmethyl) have been obtained from Ph2SnCl2 and the sodium dithiocarbamate salts of benzyl(9-anthrylmethyl)amine, benzyl(9-phenanthrylmethyl)amine, benzyl(1-pyrenylmethyl)amine, 1-naphthylmethyl(1-pyrenylmethyl)amine and di(1-pyrenylmethyl)amine. Compounds 1–5 have been analyzed as far as possible by elemental analysis, FAB+ mass spectrometry, IR, UV–Vis, fluorescence and NMR (1H, 13C, 119Sn) spectroscopy, and single-crystal X-ray diffraction analysis (1–3). The solid-state and solution studies showed that the dtc ligands are coordinated to the tin atoms in the anisobidentate manner. In all cases the metal centers are five-coordinate. The coordination geometry is intermediate between square-pyramidal and trigonal-bipyramidal coordination polyhedra with τ-values in the range of 0.49–0.55. The crystal structures show the presence of C–H···Cl, C–H···S, C–H···π, offset π–π and S···π contacts. The stability of the (Ph2SnCl)dtc complexes in the presence of the acetate anion has been examined in acetonitrile solutions. For all of these organotin(IV) complexes the displacement of the coordinated ligands (i.e., chloride and dtc) by the acetate anion was observed. The lability, as well as their intrinsic fluorescent properties of the polyaromatic moieties in these (Ph2SnCl)dtc compounds make them interesting candidates to detect the presence of O-donor anions at very low concentrations by displacement of the metal-coordinated dtc.

Five metal complexes have been prepared by reacting 3- and 4-pyridineboronic acid (3- and 4-pba) with potassium tetrachloroplatinate (K2PtCl4) and hexachloroplatinic(IV) acid hydrate (H2PtCl6·aq): [4-pbaH]2[PtCl4], [3-pbaH]2[PtCl4], [4-pbaH][Pt(4-pba)Cl3], cis-[Pt(4-pba)2Cl2]·H2O, and cis-[PtIV(3-pba)2Cl4]·2H2O. All compounds have been characterized by single-crystal X-ray diffraction analysis, showing that the primary hydrogen bonding interactions of the resulting 1D, 2D, and 3D networks contain at least one of the following synthons: X-H···Cl2Pt− (X = C, N+), B(OH)2···Cl2Pt−, and B(OH)2···(HO)2B. The dimensions are enhanced further by secondary +N−H···ClPt, O−H···O, and O−H···ClPt hydrogen bonding interactions between donor and acceptor atoms located at the periphery of these synthons. Additional weak C−H···O, C−H···Cl, B···N, and π···π stacking interactions stabilize the crystal structures further.

This contribution describes metal-organic frameworks based on cadmium-clusters that are capable of generating double-pillared architectures. A brief overview of the literature concerning such systems is presented together with the description of three new coordination polymers, [{[Cd2(trans-1,2-a,a-chdc)(trans-1,2-e,e-chdcH)2(4,4′-bpy)2]·8H2O}n] (1), [{Cd2(trans-1,4-e,e-chdc)(trans-1,4-a,a-chdc)(4,4′-bpe)2}n] (2) and[{[Cd2(cis,cis-1,3,5-chtc)(HCO2)(H2O)(4,4′-bpy)2]·DMF·4H2O}n] (3) [1,2-chdc = 1,2-cyclohexanedicarboxylate, 1,4-chdc = 1,4-cyclohexanedicarboxylate, 1,3,5-chtc = 1,3,5-cyclohexanetricarboxylate, 4,4′-bpy = 4,4′-bipyridine and 4,4′-bpe = (E)-1,2-bis(4-pyridyl)ethylene]. Compound 1 has a double-pillared two-dimensional layer structure, while compounds 2 and 3 are double-pillared three-dimensional frameworks. All materials have been characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction and thermogravimetric analysis. The robustness of the open-frameworks found for compounds 1 and 3 has been examined by X-ray powder diffraction of dried samples, which showed that the crystal structure of the 2D coordination polymer 1 collapses whereas the 3D architecture of compound 3 remains intact. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)