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Abstract: A series of organotin (IV) compounds of the type [R3SnL]2, R is Me (1), Bu (2), [R2SnL]2, R is Ph (3), Me (4), Bu (5), L is pyruvic acid thiophene-2-carboxylic hydrazone, and R2SnL, R is Me (6), Bu (7), Ph (8), L is salicylaldehyde thiophene-2-carboxylic hydrazone have been synthesized in 1:1 molar ratio. All compounds were characterized by elemental analysis, IR, 1H NMR, 13C NMR and 119Sn NMR spectra. The crystal structure of compounds 1, 3, 4, 8 have been determined by X-ray single crystal diffraction analyses, study found that the compounds 1 and 3 are rendered one-dimensional chain structure and the tin atoms are five-coordinated in a distorted trigonal-bipyramidal geometry. The compound 4 has a dimeric structure and the central tin atom is rendered seven-coordinate in a distorted pentagonal-bipyramid configuration. While the compound 8 is a monomer in which the tin atom adopts five-coordinated in distorted trigonal-bipyramidal geometry. [Copyright &y& Elsevier]

Abstract: Seven Schiff base adducts of organotin(IV), RSnLCl2, which L is o-vanillin-2-thiophenoylhydrazone, and R is n-C4H9 (1), Me (2), Ph (3), and [R2SnL], which L is o-vanillin-2-thiophenoylhydrazone, R is n-C4H9 (4), Me (5), Ph (6), PhCH2 (7) have been synthesized. Those products were characterized by elemental analysis, IR, 1H, 13C and 119Sn NMR spectra. The crystal and molecular structures of compounds 1, 4, and 6 have been determined by X-ray single crystal diffraction. In the crystal of compound 1 the tin atom is rendered six-coordinate in a distorted octahedral configuration by coordinating with the N atom of the Schiff base ligand, in compounds 4 and 6 the central tin atoms are five-coordinate in distorted trigonal-bipyramidal geometry and the comparison of the IR spectra reveal that disappearance of the bands assigned to carboxyl unambiguously conforms the ligand coordinate with the tin atom in enol form. [Copyright &y& Elsevier]

Abstract: Reactions of pyruvic acid hydrazone series [pyruvic acid thiophenecarbonyl hydrazone (L1), pyruvic acid 4-hydroxybenzoylhydrazone (L2), pyruvic acid salicyloylhydrazone (L3), pyruvic acid benzoylhydrazone (L4)], or salicylaldehyde hydrazone Schiff base ligand [salicylaldehyde isonicotinoylhydrazone (L5)] with different alkyltin salts result in six new organotin(IV) compounds, {(n-Bu)2Sn[2-SC4H3CON2C(CH3)CO2](HOC3H7-i)}2 (1), [{(n-Bu)2SnCl(O)(n-Bu)2 Sn(O)[C6H4CON2C(CH3)CO2]Sn(n-Bu)2(HOCH3)}2]∞ (2), {(o-ClBz)2Sn[4-HOC6H4CON2C(CH3) CO2] (HOC2H5)}2 (3), {(n-C8H17)2Sn[2-HOC6H4CON2C(CH3)CO2](H2O)}2 (4), {(n-Bu)2Sn[C6H5 CON2C(CH3)CO2][HOSn(n-Bu)3]}2 (5), and {[(n-C4H9)SnCl2]−[4-NHC5H4CON2CH (C6H4O-2)]+ (6), which have been characterized by single crystal X-ray diffraction, elemental analysis, IR, 1H and 119Sn NMR. In compounds 1, 3, 4, weak-bridged dimers are found, in which the two tin atoms are linked by a pair of monodentate bridges. Each pyruvic acid hydrazone ligand serves as an enolic tridentatic ligand. Compound 2 contains dimeric units of {Sn6(L2)2(n-Bu)6(HOCH3)2} that are further connected by two pairs of monodentate bridges into an 1D weak-bridged polymeric chain, in which there also exists a fascinating dichlorodistannoxane ladder structure. Studies show that the bulk and steric hindrance of the alkyl groups and the coordinated solvent molecule bonding to Sn center have little effect on the geometry of the weak-bridge for compounds 1–4. A similar weak-bridged dimeric structure is also found in compound 5; in this case, however, there is no coordinated solvent molecule and the corresponding coordination site is replaced by the trialkyltin hydroxide. Compound 6 exhibits a rare 1D supermolecular chain constructed from the zwitterionic {Sn(L5)(n-Bu)Cl2} units connected by the intermolecular N–H⋯Cl hydrogen bonds. The thermal stability of compound 1 was also studied. [Copyright &y& Elsevier]