Organotin(IV) carboxylates of cyclopropane carboxylic acid and 3‐cyclohexylpropanoic acid: synthesis,characterization and biological activity. The crystal structure of bis(cyclopropanecarboxylato) tetramethyldistannoxane

A series of tri‐ and di‐organotin(IV) derivatives of the types R₃SnL, R₂SnL₂ and [(R₂SnL)₂O]₂ have been synthesized by the reaction of tri‐ and di‐organotin(IV) chloride(s) with sodium cyclopropane carboxylate and sodium 3‐cyclohexylpropanoate. Based on spectroscopic evidence (IR and NMR), all the triorganotin carboxylates were found to be penta‐coordinated in the solid state (except the tricyclohexyltin derivative, which was found to be four‐coordinated) and four‐coordinated in the solution state. Attempted reaction of Me₂SnCl₂ with sodium cyclopropane carboxylate in 1:2 stoichiometry afforded a bis(dicarboxylato tetraorganodistannoxane) complex, {[Me₂Sn(cyclo‐CH₂)₂CHCOO]₂O}₂. The X‐ray diffraction of this ‘dimethyltin(IV) complex’ shows that the compound possesses a tetranuclear aggregate with one bridging bidentate and other free organic ester type monodentate carboxylate groups in which each Sn atom has a five‐coordinated geometry. These complexes were also screened for their antifungal activities. Copyright © 2008 John Wiley & Sons, Ltd.     

The germanium(II) ate complex [Ph3PiPr][Ge(OCOMe)3]: the first structurally characterized compound containing a discrete [E14(II)O3](−) (E14(II) = Si,Ge, Sn or Pb) anion

An X‐ray diffraction study reveals an unusual structure of the new thermally stable germanium(II) ate complex [Ph₃PⁱPr][Ge(OAc)₃] (4) containing a discrete [Ge(OAc)₃]^(?) anion containing monodentate acetate ligands with a trigonal pyramidal germanium centre. Copyright © 2005 John Wiley & Sons, Ltd.     

Synthesis,characterization and in vitro cytotoxicity of palladium(II) complexes with mixed ligands. X‐ray diffraction study of C31H36ClNPPdS2

Pd(II) complexes with organophosphines and dithiocarbamates derivatives of α‐amino acids were synthesized by reacting N,N‐dicyclohexyldithiocarbamate (DCHDTC, compounds 1 – 3 ) and N‐methylcyclohexyldithiocarbamate (MCHDTC, compounds 4 – 6 ) with (R₃P)₂PdCl₂ (R = Ph, o‐tolyl, Ph₂Cl) in a 1:1 molar ratio. The complexes were characterized by elemental analyses, FT‐IR, multinuclear (¹H, ¹³C and ³¹P) NMR and single X‐ray crystallography, showing that the dithiocarbamate acts as a bidentate ligand and binds to Pd(II) via two sulfur atoms, resulting in a square planar geometry around Pd(II). The cytotoxicity of compounds 2, 3 and 4 was determined in vitro against six human tumour cell lines, MCF7, EVSA‐T, WIDR, IGROV, M19 MEL, A498 and H226. Compounds 3 and 4 showed a moderate to low cytotoxicity, whereas compound 2 exhibited a very low cytotoxicity. The results of antifungal assays showed that compounds 1 – 6 possess antifungal activity against Fusarium moniliformes, Fusarium saolani, Mucor sp., Aspergillus niger and Aspergillus fumigatus. The anti‐inflammatory screening results of 1–6 are quite similar to those observed for the standard drug Declofenac at 10 mg kg^?1, which inhibited the odema by 74% after 4 h. Copyright © 2007 John Wiley & Sons, Ltd.     

Crystallographic report: Bis(3‐methyl‐2‐cyclopenten‐1‐one)dichloro‐oxovanadium(IV)

The crystal structure of the oxovanadium(IV) complex (CH₃C₅H₅O)₂VOCl₂ was determined. The molecule has trigonal bipyramidal geometry, with oxygen atoms of cyclopentenones in axial positions and oxygen and two chlorine atoms in equatorial positions. Copyright © 2005 John Wiley & Sons, Ltd.     

Synthesis,X‐ray structure,characterization and catalytic activity of a polymeric manganese(II) complex with iminodiacetate

A polymeric manganese(II) complex with the general formula [Mn(O₂CCH₂NH₂CH₂CO₂)₂(H₂O)₂]_n from reaction of iminodiacetatic acid and manganese(II) perchlorate under nitrogen in water, was synthesized and characterized. The structure of the complex was determined using single‐crystal X‐ray diffraction, elemental analysis, IR and UV‐vis spectra. This complex exhibited excellent catalytic activity and selectivity for oxidation of various alcohols and sulfides to the corresponding aldehydes/ketone and sulfoxides using urea hydrogen peroxide and oxone (2KHSO₅·KHSO₄·K₂SO₄), respectively, as oxidants under air at room temperature. The easy preparation, mild reaction conditions, high yields of the products, short reaction time, no over‐oxidation products, high selectivity and inexpensive system make this catalytic system a useful method for oxidizing various alcohols and sulfides. Copyright © 2011 John Wiley & Sons, Ltd.     

Synthesis and structural characterization of organotin(IV) carboxylates based on different heterocyclic substituents

Six novel organotin(IV) carboxylates have been successfully synthesized, namely, the polymer (C₆H₅)₃Sn(L1)_∞ (1) [HL1 = 4-imidazolyl benzoic acid], the mononuclear (C₆H₅)₃Sn(L2) (2) [HL2 = 4-pyrazolylbenzoic acid], (C₆H₅)₃Sn(L3)·CH₃OH (3) [HL3 = 4-triazolylbenzoic acid] and (C₆H₅)₃Sn(L4) (4) [HL4 = 4-tetrazolyl benzoic acid] and the tetranuclear [(n-Bu₂Sn)₄(L2)₂O₂(OCH₃)₂] (5) and [(n-Bu₂Sn)₄(L3)₂O₂(OCH₃)₂] (6). X-ray diffraction analyses show 1D infinite chain of polymer 1, single molecular structures of isomorphous complexes 2 and 4, single molecule structures of complex 3 containing solvent CH₃OH molecule and similar ladder-type structures of complexes 5 and 6. The photoluminescence of ligands and 1-6 were also measured in the solid state at room temperature.     

New di‐ and triorganotin(IV) carboxylates derived from a Schiff base: synthesis,characterization and in vitro antimicrobial activities

A new carboxylic acid, 2‐{[5‐(2‐nitrophenyl)furan‐2‐yl]methyleneamino}benzoic acid (HOBZ), has been produced by reacting 5‐(2‐nitrophenyl)furfural with 2‐aminobenzoic acid. Reactions of NaOBZ with organotin chlorides led to formation of [Me₃Sn(OBZ)] ( 1 ), [Bu₃Sn(OBZ)] ( 2 ), [Me₂Sn(OBZ)₂] ( 3 ) and [Bu₂Sn(OBZ)₂] ( 4 ). Complexes 1 , 2 , 3 , 4 have been characterized using elemental analyses and infrared, ¹H NMR, ¹³C NMR, ¹¹⁹Sn NMR and ¹¹⁹Sn Mössbauer spectroscopies. In the solid state, the OBZ ligands might coordinate to tin in an anisobidentate fashion via the carboxylate group. The in vitro antimicrobial activity of all compounds has been screened against the following fungi: Aspergillus niger, A. flavus, A. parasiticus, Penicillium citrinum, Candida dubliniensis, C. lusitaniae, C. albicans, C. tropicalis, C. parapsilosis and C. glabrata; and against the following bacteria: Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Streptococcus sanguinis, Escherichia coli, Citrobacter frendii, Salmonella typhimurium and Pseudomonas aeruginosa. Complexes 2 and 4 exhibited higher biocide activity in comparison to 1 and 3 and to the control drugs nystatin and miconazole nitrate for the yeasts, and chloramphenicol and ampicillin for the bacteria. The biological activity of 2 was superior to that of 4 . In addition, the toxicity of HOBZ, NaOBz and 1 , 2 , 3 , 4 were determined using Chlorella vulgaris, revealing low toxicity of the complexes at MIC₅₀ concentrations. We also performed cell viability studies, using XTT assay, displaying no change in the mitochondrial function after 2–4 h of exposure of the microorganism to the complexes at MIC₅₀ concentrations. The butyl‐containing complexes 2 and 4 display greater lipophilicities than do the methyl analogues 1 and 3 , thereby endowing 2 and 4 with superior abilities to cross the microbe cell membrane, the possible mechanism of action. Copyright © 2015 John Wiley & Sons, Ltd.     

二茂铁羧酸及含氮配体构筑的锌(II)和镉(II)配合物的合成、晶体结构及电化学性质

使Zn(OAc)₂·2H₂O或Cd(OAc)₂·2H₂O与邻羧基苯甲酰二茂铁钠(o-OOCC₆H₄COFcNa；Fc=(η⁵-C₅H₅)Fe(η⁵-C₅H₄))和1，10-邻菲咯啉(phen)在甲醇中反应，合成了含有混合配体的单核配合物[Zn(o-OOCC₆H₄COFc)₂(phen)(H₂O)]·CH₃OH (1)和双核配合物{[Cd(η²-o-OOCC₆H₄COFc)( μ₂-o-OOCC₆H₄COFc)(phen)]·CH₃OH₂·H₂O}₂ (2)。晶体结构表明：在1中，单核的结构单元通过分子间氢键形成了一维的长链结构；在2中，o-FcCOC₆H₄COO^-以及phen均双齿螯合中心Cd(II)离子，随后在o-FcCOC₆H₄COO^-的双齿桥联下，形成一个双核结构。研究了这2个配合物在DMF溶液中的电化学性能。     

Luminescence characteristics and X‐ray crystal structure of [Cd(bipy)3][PF6]2 (bipy = 2,2′‐bipyridine)

The photoluminescence characteristics of the [Cd(bipy)₃][PF₆]₂ complex are reported. A moderately large quantum yield (φ) of 1.07 × 10^?2 is exhibited in acetonitrile solution at 298 K. Crystallography shows the dication to have a distorted octahedral geometry and the crystal structure to be stabilized by C? H···π and C? H···F interactions. Copyright © 2005 John Wiley & Sons, Ltd.     

Crystallographic report: Bis[3‐(tri‐p‐tolyl)germyl‐3‐(o‐tolyl)‐propionato]dibutyltin(IV)

The crystal structure of [(p‐CH₃C₆H₄)₃GeCH(o‐CH₃C₆H₄)CH₂CO₂]₂Sn(C₄H₉)₂ consists of a monomer with the atoms of tin and germanium both occupying tetrahedral geometries. However, the tin atom is distorted towards a skew trapezoidal bipyramid geometry as a result of weakly chelating carboxylate ligands. Copyright © 2003 John Wiley & Sons, Ltd.     

Crystallographic report: Bis[N,N‐dimethyl‐N′‐(pyrid‐2‐ylmethyl)‐ethylenediamine]zinc(II) diperchlorate

The zinc(II) atom in the centrosymmetric complex is in a distorted N₆ octahedral geometry defined by two tridentate ligands. Copyright © 2004 John Wiley & Sons, Ltd.     

Solution behaviour of lead(II) carboxylates in organic solvents

The solution behaviour has been studied of a series of even chain length lead(II) carboxylates (octanoate to octadecanoate) and the odd chain length lead(II) heptadecanoate in a variety of non-complexing organic solvents and in alcohols. In agreement with previous studies, solubility increases dramatically above a certain temperature, which depends on solute concentration, chain length and solvent. This solution temperature is also affected by traces of water. These results are complemented by studies using vapour pressure osmometry, dynamic light scattering, ¹H and ¹³NMR spectroscopy. The results in water-free systems are consistent with the formation of rather ill-defined, polydisperse aggregates, which increase in size with concentration and decrease with temperature. These show similar local structure to lamellar mesophases in the pure lead(II) carboxylates, and are suggested to be formed by solvent induced swelling and break-up of these mesophases. In the presence of water, a more ordered structure is formed, in which a few water molecules are suggested to be bound to the lead(II) carboxylate headgroup.     

Gravimetric Determination of Mercury(II) and Vanadium(IV) with Benzoylacetanilide

Abstract

Gravimetric methods for the determinations of mercury(II) and vanadium(IV) with benzoylacetanilide have been described. These metals have been separated from commonly associated ions and a procedure for the determination of vanadium content of steel has been developed. By these methods, 14 to 50 mg. of mercury and 5 to 20 mg. of vanadium have been estimated with relative standard deviations of 0.18% and 0.10%, respectively.     

Bis(p‐nitrobenzoxasulfamato) Complexes of Cadmium(II) and Mercury(II) ‐ Synthesis,Spectra, and X‐Ray Crystal Structures

The reaction of sodium benzoxasulfamate (nbs) with cadmium(II) and mercury(II) sulfate in aqueous solution yield the novel complexes [Cd(nbs)₂(H₂O)₄] (1) and [Hg(nbs)₂(H₂O)₃] ( 2 ), respectively. The complexes were characterized by elemental analyses, IR spectroscopy and X‐ray crystallography. Complex 1 is monomeric and has an octahedral arrangement in which the N‐donor nbs ligands occupy the axial positions, while the water oxygen atoms form the equatorial plane. Complex 2 is polymeric and shows a pentagonal bipyramidal arrangement achieved by the bridging of the HgN₂O₃ units through the weak interaction of the O atoms of the nitro group. The nbs ligands also occupy the axial positions of the pentagonal bipyramid, whereas three water and two nitro oxygen atoms constitute the pentagonal plane. The crystal structure packing in both crystals is achieved by the intermolecular hydrogen bonds involving water hydrogen atoms, nitro and sulfonyl oxygen atoms.     

Novel platinum(II) and (IV) complexes of naphthaldimine schiff bases

Naphthaldimines containing N₂O₂ donor centers react with platinum(II) and (IV) chlorides to give two types of complexes depending on the valence of the platinum ion. For [Pt(II)], the ligand is neutral, [(H₂L¹)PtCl₂]·3H₂O (1) and [(H₂L³)₂Pt₂Cl₄]·5H₂O (3), or monobasic [(HL²)₂Pt₂Cl₂]·2H₂O (2) and [(HL⁴)₂Pt]·2H₂O (4). These complexes are all diamagnetic having square-planar geometry. For [Pt(IV)], the ligand is dibasic, [(L¹)Pt₂Cl₄(OH)₂]·2H₂O (5), [(L²)Pt₃Cl₁₀]·3H₂O (6), [(L³)Pt₂Cl₄(OH)₂]·C₂H₅OH (7) and [(L⁴)Pt₂Cl₆]·H₂O (8). The Pt(IV) complexes are diamagnetic and exhibit octahedral configuration around the platinum ion. The complexes were characterized by elemental analysis, UV-Vis and IR spectra, electrical conductivity and thermal analyses (DTA and TGA). The molar conductances in DMF solutions indicate that the complexes are non-ionic. The complexes were tested for their catalytic activities towards cathodic reduction of oxygen.     

Total‐reflection X‐ray diffraction study of friction‐transferred poly(tetrafluoroethylene) film

The orientational structure of the friction‐transferred poly(tetrafluoroethylene) (PTFE) film, which consists of highly oriented polymer strands, was evaluated with energy‐dispersive total‐reflection X‐ray diffractometry. In the film, each PTFE molecule is oriented along the friction direction, and PTFE crystallites have a preferred orientation with respect to the substrate surface. The orientational distribution of the chain direction was quantitatively evaluated. The half‐width of the distribution was determined to be about 3°. The dependence of the orientational distribution on temperature is discussed. © 2001 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 39: 432–438, 2001     

Two new zinc(II) and mercury(II) complexes based on N,N′‐(cyclohexane‐1,2‐diylidene)bis(4‐fluorobenzohydrazide): synthesis,crystal structures and antibacterial activities

Reaction of N,N′‐(cyclohexane‐1,2‐diylidene)bis(4‐fluorobenzohydrazide), C₂₀H₁₈F₂N₄O₂, ( L^F ), with zinc chloride and mercury(II) chloride produced different types and shapes of neutral coordination complexes, namely, dichlorido[N,N′‐(cyclohexane‐1,2‐diylidene)bis(4‐fluorobenzohydrazide)‐κ²N,O]zinc(II), [ZnCl₂(C₂₀H₁₈F₂N₄O₂)], ( 1 ), and dichlorido[N,N′‐(cyclohexane‐1,2‐diylidene)bis(4‐fluorobenzohydrazide)‐κ⁴O,N,N′,O′]mercury(II), [HgCl₂(C₂₀H₁₈F₂N₄O₂)], ( 2 ). The organic ligand and its metal complexes are characterized using various techniques: IR, UV–Vis and nuclear magnetic resonance (NMR) spectroscopies, in addition to powder X‐ray diffraction (PXRD), single‐crystal X‐ray crystallography and microelemental analysis. Depending upon the data from these analyses and measurements, a typical tetrahedral geometry was confirmed for zinc complex ( 1 ), in which the Zn^II atom is located outside the bis(benzhydrazone) core. The Hg^II atom in ( 2 ) is found within the core and has a common octahedral structure. The in vitro antibacterial activities of the prepared compounds were evaluated against two different bacterial strains, i.e. gram positive Bacillus subtilis and gram negative Pseudomonas aeruginosa bacteria. The prepared compounds exhibited differentiated growth‐inhibitory activities against these two bacterial strains based on the difference in their lipophilic nature and structural features.     

Synthesis,characterization and antimicrobial activities of triorganotin(IV) complexes with azo-azomethine carboxylate ligands: crystal structure of a tributyltin(IV) and a trimethyltin(IV) complex

Triorganotin(IV) complexes with polyaromatic azo-azomethine carboxylate ligands viz. 2-{4-hydroxy-3-[(2/4-hydroxyphenylimino)methyl]phenylazo}benzoic acids [H₃L¹/H₃L²] were synthesized by reacting the ligands with either bis-tri-n-butyltin(IV) oxide (for 1 and 4) or trimethyltin(IV) chloride in presence of triethylamine (for 2 and 5) or triphenyltin(IV) hydroxide (for 3 and 6). The complexes were characterized by elemental analysis, UV, IR, NMR, and mass spectrometry. NMR spectroscopic studies of the compounds suggested that the complexes adopt four-coordinate tetrahedral geometry around tin in solution. Molecular structures of 1 and 2 were determined by single-crystal X-ray diffraction. Both complexes have distorted trigonal bipyramidal geometry around tin in the solid state. Compound 1 is a one-dimensional (1-D) double chain coordination polymer which can be described as two different 24- and 30-membered non-porous macrocyclic rings constructed from two tributyltin units and two ligand moieties. The structure of 2 comprises a discrete cyclic centrosymmetric dimer with two lattice water molecules per formula unit. In the dimer, two trimethyltin entities are bridged by two ligand moieties. The dimers are further interconnected with lattice water molecules by multiple O–H?O hydrogen bonds to form a 1-D H-bonded network. The complexes were also screened for their antimicrobial activities.