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The alkali metal (Li + , Na + , K + , Rb + , Cs + ) carboxylate-dithiocarbamate complexes of L -proline have been prepared from the reaction of L -proline with carbon disulfide in the presence of two equivalents of the corresponding alkali metal hydroxide. The resulting compounds have been characterized by FAB + mass spectrometry, IR spectroscopy, NMR ( 1 H, 13 C) spectroscopy. The X-ray single crystal crystallography analysis of the complexes of K + , Rb + and Cs + complexes showed that the coordination modes of dithiocarbamate and carboxylate groups to the alkali metal is modulated by the resonance effect, the ionic radius of the sulfur and oxygen atoms as well as the size, charge-density, and Lewis-acidity of the metal ions. In this way in the solid state polymeric structures in 2D for K + and Rb + complexes, and 3D in the case of Cs + are generated. The distances C···M, M···S1 and M···S2 suggest the existence of cation···π and van der Waals interactions that can be described as a η 3 coordination mode of the dtc group to the alkali metal ions.

In order to test the possible presence of the intramolecular interactions O → M in the group 14 elements and its consequences on the geometry, the 2-methoxybenzyl chlorine was reacted with magnesium and subsequently with the group 14 chlorides, Ph3MCl, to produce the organometallic compounds (2-CH3OC6H4)CH2MPh3 [M = Si (1), Ge (2) and Pb (3)]. The compounds were fully characterized by elemental analysis, infrared spectroscopy, mass spectrometry (FAB+), and multinuclear (1H, 13C, 29Si, 207Pb) NMR spectroscopy. The compounds 1 and 2 also were investigated by single crystal X-ray diffraction analysis, they are isostructural with a triclinic crystal system and P-1 space group, exhibiting a distorted tetrahedral environment. The possible intramolecular O → M distances in 1 and 2 are 3.810 A and 3.802 A respectively, and represent more than the 100% of the sum of the appropriate Van der Waal’s radii. By comparison, in the previously reported tin analogous compound, that is not part of this work, the intramolecular distance O → Sn is ∼80% of the sum of the Van der Waal’s radii. The molecular structures of the four organometallic complexes were fully studied within the Density Functional Theory formalism.

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.

Eighteen mononuclear diorganotin(IV) complexes derived from tridentate Schiff bases and R2SnO (IV) oxides (R = Me, n-Bu, Ph) were synthetized by multicomponent reactions in moderate yields. Complexes were characterized by common spectroscopic techniques such as FT-IR, UV–vis, mass spectrometry and NMR (1H, 13C and 119Sn) spectroscopy analysis. Nine complexes were characterized by single crystal X-ray diffraction analysis (1c, 1d, 1g, 1k, 1n, 1o, 1p, 1q and 1r). 119Sn NMR spectra showed signals at δ = 135–145, 175–185 and 319–323 ppm for Me, n-Bu and Ph derivatives respectively, indicating the pentacoordination of the tin atoms. In solid state, for compounds 1c, 1d, and 1g a distorted octahedral geometry for tin atoms was observed owing the presence of intermolecular Sn⋯O interactions, while for compounds 1k, 1n-1r, the pentacoordinate environment for tin atoms is observed. At supramolecular level the presence of O H⋯O, C H⋯O, C H⋯X (X = Cl, Br), C H⋯π and π⋯π interactions allow the formation of 1D and 2D polymeric chains.

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.

The synthesis and characterization of six new O-cholesteryl-dithiophosphonates containing thio-metalloheterocycles of As(III) and Sb(III); (CH2S)2As[S2P(cholesteryl)(4-MeOC6H5)] (2), (CH2S)2Sb[S2P(cholesteryl)(4-MeOC6H5)] (3), O(CH2CH2S)2As[S2P(cholesteryl)(4-MeOC6H5)] (4), O(CH2CH2S)2Sb[S2P(cholesteryl)(4-MeOC6H5)] (5), S(CH2CH2S)2As [S2P(cholesteryl)(4-MeOC6H5)] (6), and S(CH2CH2S)2Sb[S2P(cholesteryl)(4-MeOC6H5)] (7) are reported. 2–7 have been prepared from the reaction between the triethylammonium salt of O-3β-cholest-5-en-3-yl (4-methoxyphenyl) dithiophosphonate (1) and five and eight membered chloro-metalloheterocycles of As(III) and Sb(III). The obtained compounds have been characterized by elemental analyses, IR and NMR (1H, 13C, and 31P) spectroscopy. The 31P NMR data suggest that the dithiophosphonate ligand presents, in solution, a bidentate coordination. The structures of 3 and 4 were determined by X-ray single crystal analysis, that correspond to the first examples of such determinations in Group 15 dithiophosphonates, showing an anisobidentate coordination mode of the dithiophosphonate moiety. Sb(III) and As(III) in compounds 3 and 4 present tetracoordination and pentacoordination, respectively. The pentacoordination in 4 is achieved through a 1,5 transannular As⋯O interaction. Antibacterial assays were performed and the activity was correlated with the electronic distribution and molecular shape, employing their geometrical structures, Mulliken partial charges, dipole moments and Molecular Electrostatic Potential maps from DFT calculations.