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Two ionic triphenyltin complexes were obtained when two thiocarboxylic acids, mercaptoacetic acid and 3-mercaptopropionic acid, were mixed with triphenyltin hydroxide in the presence of dicylcohexylamine. Their structures have been characterized by IR and multi-nuclear (1H, 13C{1H} and 119Sn{1H}) NMR spectroscopies. Coordination difference was observed between triphenyltin complexes of mercaptoacetate and 3-mercaptopropionate. The coordination assignments of the tin atoms in the two triphenyltin complexes are confirmed by X-ray crystallographic studies. In the solid state, the bidentate binding mode of mercaptoacetate ligand gives a five-coordinate ionic triphenyltin complex with a cis-trigonal-bipyramid (TBP) geometry around tin, while the tin in dicyclohexylammonium 3-mercaptopropionatotriphenylstannate was found to be four-coordinate with tetrahedral geometry around tin, as the 3-mercaptopropionate is monodentate via sulfur. Important hydrogen bonding between dicyclohexylammonium and carboxylate have been observed for both complexes. [ABSTRACT FROM AUTHOR]

Two ionic triphenyltin complexes (1and2) were obtainedviacondensation of triphenyltin hydroxide with oxalic and malonic acids in the presence of di-isobutylamine. Their structures have been characterized by IR and multinuclear (1H,13C, and119Sn) NMR spectroscopies. The coordinations of tin in the two triphenyltin complexes are confirmed by X-ray crystallographic studies. In the solid state, oxalate complex1consists of a di-isobutylammonium cation and an oxalatotriphenylstannate anion. Tin is five-coordinate with acis-trigonal-bipyramid (TBP) geometry, as the oxalate is a chelating bidentate ligand. Complex1is a 1-D polymerviahydrogen bonding between carboxylate oxygen and ammonium nitrogen. The crystallographic studies reveal that2is a trinuclear triphenyltin complex formed with the molar ratio of tin, acid, and amine being 3?:?2?:?1. A negative charge is delocalized among the three tins in the complex; all tins havetrans-TBP geometry with three phenyls in the equatorial plane and two O in axial positions. The malonates in2are bridging tridentate with the free carbonyl hydrogen bonded to di-isobutylammonium through an ethanol. This coordination and significant inter- and intramolecular hydrogen bonds between ammonium and malonate result in a 3-D polymeric structure for2. [ABSTRACT FROM PUBLISHER]

New triorganotin(IV) derivatives of dipeptides with general formulae, R3Sn(HL), where R = Me and Ph, and HL is the monoanion of histidinylalanine and histidinylleucine, have been synthesized and characterized on the basis of infrared (IR), multinuclear NMR (1H,13C, and119Sn), and119Sn Mössbauer spectroscopic studies. These derivatives exhibit distorted trigonal-bipyramidal geometry around tin in which dipeptide anion acts as bidentate ligand coordinating through carboxyl oxygen and amino nitrogen. Ph3Sn(HHis-Ala), Ph3Sn(HHis-Leu), and previously reported Ph2Sn(His-Ala), Me2Sn(His-Ala), n-Oct2Sn(His-Ala), Me2Sn(His-Leu), n-Oct2Sn(His-Leu), Ph3Sn(HTyr-Phe), Ph2Sn(Tyr-Phe), Bu2Sn-(Tyr-Phe), and n-Oct2Sn(Tyr-Phe) along with standard drugs, viz. phenyl butazone and indomethacin were screened for in vivo anti-inflammatory activity and acute toxicity (LD50). Diorganotin(IV) derivatives are more active than triorganotin(IV) derivatives. Me2Sn(His-Leu) shows the highest activity. Supplemental materials are available for this article. Go to the publisher's online edition ofPhosphorus, Sulfur, and Silicon and the Related Elementsto view the free supplemental file. [ABSTRACT FROM AUTHOR]

A series of cis-bis{5-[(E)-2-(aryl)-l-diazenyl]quinolin-8-olato(dimethyltin(IV), Me2Sn(L)2, and chloro-{5-[(E)-2-(aryl)-l-diazenyl]quinolin-8-olato}dimethyltin(IV), Me2SnCl(L), complexes have been synthesized by reacting the sodium salts of 5-[(E)2-(aryl)-l-diazenyl)quinolin-8-ol (LH) and dimethyltin dichloride in 2:1 and 1:1 molar ratios, respectively. These complexes have been characterized by 1H, 13C, 119Sn NMR in solution and by IR and 119Sn Mössbauer spectroscopy in the solid state. The structures of two of the dimethyltin(IV) complexes, viz., Me2Sn(L2)2 (2) and Me2SnCl(L3). C7H8 (6) (L2 = 5-[(E)-2-(4'-methoxyphenyl)-l-diazenyl)quinolin-8-olate, L3 = 5-[(E)-2-(4'-ethoxy-phenyl)-l-diazenyl)quinolin-8-olate), were determined by single crystal X-ray diffraction. In general, the Me2Sn(L)2 complexes were found to adopt a distorted crá-octahedral arrangement, while Me2SnCl(L) complexes have a distorted trigonal bipyramidal coordination geometry around the tin atom in solution and in the solid state. [ABSTRACT FROM AUTHOR]

In an attempt to prepare potassium/sodium salts of malonato-triphenylstannate, two bis(triphenyltin) malonates were obtained instead, [(C6H5)3Sn]3[O2CCH2CO2]1.5 (1) and {[(C6H5)3SnO2CCH2CO2Sn(C6H5)3]H2O}CH3CH2OH (2). This provides an excellent example of structural diversity in triorganotin carboxylates. In both complexes, the dicarboxylate was connected to the triphenyltin groups forming a linear infinite polymeric chain. Both complexes have a trans-trigonal bipyramidal geometry with the three phenyl groups occupying the equatorial plane and two oxygens at axial positions. Both short and long tin-oxygen distances were observed in 1 and 2. In 1, all carboxylates functioned as bridging bidentate ligands, resulting in an infinite 3-D polymer network propagating along all three axes. In 2, Sn1 is bonded to a carboxylate and a water molecule (Sn1-O1 2.145(3) Å, Sn1-O3 2.341(3) Å, O1-Sn1-O3 173.97(12)°). Only one carboxylate acts as a bidentate ligand allowing the carbonyl group to be axially coordinated to the adjacent tin, Sn2. Also, Sn2 is covalently bonded to the other carboxylate group in the malonate ligand (Sn2-O4 2.163(3) Å, Sn2-O5 2.353(3) Å, O4-Sn2-O5 173.47(12)°). There is a water molecule included in the crystal lattice hydrogen bonded to the uncoordinated carbonyl in malonate. [ABSTRACT FROM AUTHOR]

New organotin(IV) complexes with empirical formula Sn(SNNNS)R2, where SNNNS is the dianionic form of 2,6-diacetylpyridine Schiff bases of S-methyldithiocarbazate (H2dapsme) or S-benzyldithiocarbazate (H2dapsbz) and R = Ph or Me, have been prepared and characterized by IR, UV-Vis, NMR and Mossbauer spectroscopic techniques and conductance measurements. The molecular structures of the Sn(dapsme)R2 (R = Ph and Me) have been determined by single crystal X-ray diffraction techniques. Both complexes have a distorted pentagonal-bipyramidal geometry in which the tin is coordinated by a dinegatively charged pentadentate chelating agent via pyridine nitrogen, two azomethine nitrogens, and two thiolate sulfurs. The five donors (N3S2) provided by the Schiff base occupy the equatorial plane close to a pentagonal planar array while the carbanion ligands occupy axial sites. [ABSTRACT FROM AUTHOR]

This article describes the synthesis and characterization of several new diorganotin(IV) tetraazamacrocyclic complexes. The template condensation of anthranilic acid and diethylenetriamine with 1,2-dibromoethane or 1,3-dibromopropane in the presence of diorganotin(IV) dichlorides yielded macrocyclic complexes. The geometry and the mode of bonding of the resulting complexes were inferred from elemental analysis, UV-Vis, IR, Direct Analysis in Real Time-mass, (1H, 13C and 119Sn) NMR, and 119mSn Mossbauer spectral studies. These studies suggested that the macrocyclic ligands are tetradentate, coordinating through four nitrogens giving a skew-trapezoidal bipyramidal environment around tin in the [R2Sn(L-1)/(L-2)] (R = Me, n-Bu and Ph; H2L-1/H2L-2 = macrocyclic ligands) complexes. Thermal studies of the complexes were carried out in the temperature range 25-1000°C using thermogravimetry, derivative thermogravimetry, and differential thermal analysis techniques which provided a simple route to nanosized semi conducting SnO2 grains, identified by X-ray diffraction analysis. The particle size of the residue, obtained by pyrolysis of 2, 3, 4 and 5, determined by X-ray line broadening and transmission electron microscope were in the range ∼38-48 nm and ∼3-20 nm, respectively. The surface morphology of these residues was determined by scanning electron microscopy. [ABSTRACT FROM AUTHOR]

Two structurally different triphenyltin complexes of thiosalicylic acid were obtained depending on the amine used. Bis(triphenyltin) thiosalicylate was obtained when diethylamine was used while dicyclohexylammonium thiosalicylatotriphenylstannate resulted with dicyclohexylamine. Their structures have been characterized by IR and multi-nuclear (1H, 13C, 119Sn) NMR spectroscopies. In the solid state, both tins in the bis(triphenyltin) thiosalicylate complex are four-coordinate while the tin in dicyclohexylammonium thiosalicylatetriphenylstannate is five-coordinate. However, in solution, dissociation occurs in the dicyclohexylammonium thiosalicylatotriphenylstannate complex reducing the coordination of tin to four. The coordination of the tin atoms in the two triphenyltin complexes is confirmed by X-ray crystallographic studies. [ABSTRACT FROM AUTHOR]

New diphenyltin(IV) derivatives of the formula Ph2SnL, where L is the dianion of glycyltryptophan(Gly-Trp), glycylphenylalanine(Gly-Phe), valylvaline(Val-Val), alanylvaline(Ala-Val), and leucylalanine(Leu-Ala), have been synthesized by the reaction of Ph2SnCl2 and the disodium salt of the respective dipeptides. The bonding and coordination behaviour in these derivatives are discussed on the basis of IR, multinuclear 1H, 13C, and 119Sn NMR and 119Sn Mössbauer spectroscopic studies. These investigations suggest that all the dipeptides in Ph2SnL act as dianionic tridentate ligands coordinating through the COO−, NH2, and Npeptide groups. The 119Sn Mössbauer studies, together with the NMR data, suggest a trigonal-bipyramidal geometry around tin in Ph2SnL with the phenyl groups and Npeptide in the equatorial positions, whereas a carboxylic oxygen and the amino nitrogen atom occupy the axial positions. The anti-inflammatory and cardiovascular activities, and toxicity of all the synthesized diphenyltin(IV) derivatives of dipeptides and of n-dibutyltin(IV) derivatives of dipeptides(synthesized and characterized earlier) viz. Gly-Trp, Val-Val, Ala-Val, glycyltyrosine(Gly-Tyr), leucyltyrosine(Leu-Tyr), and leucylleucine(Leu-Leu) are discussed. The n-dibutyltin(IV) derivatives exhibit better cardiovascular and anti-inflammatory activities than the diphenyltin(IV) analogues. [ABSTRACT FROM AUTHOR]

In an effort to develop new organotin(IV) compounds of industrial and biological importance, a series of di- and triorganotin(IV) complexes of(E)-3-(4-chlorophenyl)-2-phenylpropenoic acid with the general formula R4-nSnLn have been synthesized by the reaction of the corresponding organotin chlorides with the sodium salt of(E)-3-(4-chlorophenyl)-2-phenylpropenoic acid(C15H10ClO2Na) where, R = CH3, C2H5, n-C4H9, C6H5, C6H5 · CH2, n = 1 or 2 and L = acid anion(C15H10ClO2−). The dimeric tetraorganodicarboxylatodistannoxanes[(Me2SnL)2O]2 compound(2) and[(Bu2SnL)2O]2 compound(4), L = C15H10ClO2−, were synthesized by the reaction of R2SnO with the ligand acid(HL) in 1:1 molar ratio with azeotropic removal of water. The structures of the complexes are discussed on the basis of IR, multinuclear(1H, 13C, 119Sn) NMR, 119mSn Mössbauer spectroscopies and mass spectrometry. The spectroscopic results substantiate that all the diorganotin(IV) derivatives possess trigonal-bipyramidal structures in solution and octahedral geometry in the solid state. A linear polymeric trigonal-bipyramidal structure in the solid state and a tetrahedral environment around the tin atom in non-coordinating solvents has been proposed for the triorganotin(IV) derivatives. TheΔν[Δν = νasym(COO) − νsym(COO)] values obtained from the IR data, in comparison to the ligand acid and its sodium salt, fall in the range which shows that the ligand may act as a bidentate coordinating group through the carboxyl(COO) oxygen atoms. The biological activity and LD50 data of the synthesized compounds are also reported. The triorganotin(IV) complexes exhibit significantly better activities than the diorganotin(IV) derivatives. The LD50 data show that most of the investigated compounds are cytotoxic. [ABSTRACT FROM AUTHOR]