Biocidal organotin compounds: Part 1. Preparation and characterization of triorganotin(IV) 4-pyridyl- and 2-pyrimidyl- thioacetates and the crystal structure of triphenyltin(2-pyrimidylthioacetate)

The preparation and spectroscopic characterization of [R₃Sn(O₂CCH₂SC₅H₄N-4)], R == Ph, benzyl (Bz), cyclohexyl (c-Hex) and n-Bu, and of [R₃Sn(O₂CCH₂SC₄H₃N₂-2,6)], R == Me, Ph and n-Bu, are reported. The 2-pyrimidyl compounds feature trigonal bipyramidal tin centres with trans-R₃SnO₂ geometries as was confirmed by X-ray crystallography for [Ph₃Sn(O₂CCH₂SC₄H₃N₂-2,6)]. ¶ By contrast the 4-pyridyl compounds have trigonal bipyramidal geometries in the solid state (arising from intermolecular Sn…N interaction) and tetrahedral geometries in solution. The biocidal activity of these compounds against the fungi Helminthosporium maydis (ITCC 2675) and H. oryzae (ITCC 2675), both of which damage crops such as maize and rice, shows promise. Encouraging is the observation that the compounds show no adverse phytotoxicity at concentrations to 10^?3M.     

Synthesis,structure and cytotoxic activity of diethyltin N‐[(2‐oxyphenyl)methylene]phenylalaninates

Four new diethyltin N‐[(2‐oxyphenyl)methylene]phenylalaninates, (CH₃CH₂)₂Sn[2‐O‐3‐X‐5‐YC₆H₂CH?NCH(CH₂Ph)COO] (X, Y = H, H, 1 ; H, Br, 2 ; H, OCH₃, 3 ; Br, Br, 4 ), have been synthesized and characterized using elemental analysis and infrared and NMR (¹H, ¹³C and ¹¹⁹Sn) spectra. The crystal structures of 1 , 2 , 3 , 4 have been determined. Compounds 1 and 2 have a 12‐membered macrocyclic structure with a trimeric [Sn₃O₆C₃] core. Each tin atom is six‐coordinated in distorted [SnC₂NO₃] octahedral geometry. Compound 3 is a centrosymmetric weak dimer in which the two tin centers are linked by two asymmetric Sn? O???Sn bridges involving the phenolic oxygen of the ligand and two Sn???O interactions from ether oxygen of the adjacent ligand. The coordination geometry of the tin atom can be described as a distorted pentagonal bipyramid with two ethyl groups in axial positions. Compound 4 is a novel binuclear tin complex, formed by the carboxylate of a ligand asymmetrically bridging two tin atoms, which contains a five‐coordinated tin and a six‐coordinated tin. Bioassay results have shown that the compounds have weak in vitro activity against two human tumor cell lines, A549 and CoLo205. Copyright © 2016 John Wiley & Sons, Ltd.     

Synthesis, spectral characterization and biological studies of some organotin(IV) complexes of L-proline, trans-hydroxy-L-proline and L-glutamine

New organotin(IV) complexes of the general formula R3Sn(L) (where R=Me, n-Bu and HL=L-proline; R=Me, Ph and HL=trans-hydroxy-L-proline and L-glutamine) and R2Sn(L)2 (where R=n-Bu, Ph and HL=L-proline; R=Ph, HL=trans-hydroxy-L-proline) have been synthesized by the reaction of RnSnCl(4-n) (where n=2 or 3) with sodium salt of the amino acid (HL). n-Bu2Sn(Pro)2 was synthesized by the reaction of n-Bu2SnO with L-proline under azeotropic removal of water. The bonding and coordination behavior in these complexes have been discussed on the basis of IR and 119Sn M?ssbauer spectroscopic studies in the solid-state. Their coordination behavior in solution has been discussed with the help of multinuclear (1H, 13C and 119Sn) NMR spectral studies. The 119Sn M?ssbauer and IR studies indicate that L-proline and trans-hydroxy-L-proline show similar coordination behavior towards organotin(IV) compounds. Pentacoordinate trigonal-bipyramidal and hexacoordinate octahedral structures, respectively, have been proposed for the tri- and diorganotin(IV) complexes of L-proline and trans-hydroxy-L-proline, in which the carboxylate group acts as bidentate group. L-glutamine shows different coordination behavior towards organotin(IV) compounds, it acts as monoanionic bidentate ligand coordinating through carboxylate and amino group. The triorganotin(IV) complexes of L-glutamine have been proposed to have trigonal-bipyramidal environment around tin. The newly synthesized complexes have been tested for their antiinflammatory and cardiovascular activities. Their LD50 values are >1000 mg kg-1.     

Reactions of in situ generated hydrated organotin cations with chelating O,O- or O,N-ligands: a possible structure-directing influence of the organic substituent on tin

The reaction of [n-Bu(2)SnO](n) with 1,5-naphthalenedisulfonic acid tetrahydrate in a 1:1 stoichiometry followed by reaction with 2,2'-bipyridine-N,N'-dioxide (BPDO-I) afforded a 1D-coordination polymer [n-Bu(2)Sn(BPDO-I)(1,5-C(10)H(6)(SO(3))(2))](n) (1) where the disulfonate ligand acts as a bridging ligand between two tin centers. An analogous reaction involving [Ph(2)SnO](n) afforded a trihydrated O,O'-chelated diorganotin cation [{Ph(2)Sn(BPDO-I)(H(2)O)(3)}(2+)][C(10)H(6)(SO(3)(-))(2)]·2CH(3)OH (2·2CH(3)OH). Utilizing two equivalents of BPDO-I in this reaction resulted in the ionic complex [{Ph(2)Sn(BPDO-I)(2)(H(2)O)}(2+)][C(10)H(6)(SO(3)(-))(2)]·3H(2)O (3·3H(2)O). In 2 and 3 the sulfonate ligands are not present in the coordination sphere of tin. Reaction of [n-Bu(2)SnO](n) and 1,5-naphthalenedisulfonic acid tetrahydrate, followed by reaction with [bis(diphenylphosphoryl)methane (DPPOM)] resulted in the formation of, [{n-Bu(2)Sn(DPPOM)(2)(H(2)O)(1,5-C(10)H(6)(SO(3))(SO(3)(-))}]·H(2)O (4·H(2)O). Of the two coordinating groups present in DPPOM, only one P=O group is coordinated to the tin atom. The remaining P=O motif is free and is involved in intramolecular H-bonding with the tin-bound water molecule. Using [Ph(2)SnO](n) instead of [n-Bu(2)SnO](n) afforded the ionic complex [{Ph(2)Sn(DPPOM)(2)}(2+){1,5-C(10)H(6)(SO(3)(-))(2)}] (5) where the DPPOM functions as a chelating ligand. The reaction of [n-Bu(2)SnO](n) with 1,5-naphthalenedisulfonic acid tetrahydrate followed by addition of one equivalent of 8-hydroxyquinoline (8-HQ) in presence of triethylamine afforded the neutral dinuclear complex, [(H(2)O)(8-Q)n-Bu(2)Sn(μ-1,5-C(10)H(6)(SO(3))(2))n-Bu(2)Sn(8-Q)(H(2)O)] (6) where the two tin atoms are bridged by the disulfonate ligand. Compounds 1-6 are thermally stable as shown by their thermogravimetric analyses.     

Synthesis, characterization, and hydrolytic behavior of mixed-ligand diorganotin esters, [R2Sn(O2CR')OSO2Me]2 (R=n-Pr, n-Bu; R'=C9H6N-2, 4-OMe-C9H5N-2, C9H6N-1)

Reactions of the tin precursors, R2Sn(OMe)OSO2Me (R=n-Pr, n-Bu), with an equimolar quantity of 2-quinoline/4-methoxy-2-quinoline/1-isoquinoline carboxylic acid in acetonitrile proceed under mild conditions (rt,12-15 h) via selective Sn-OMe bond cleavage to afford the corresponding mixed-ligand diorganotin derivatives [R2Sn(O2CR')OSO2Me]2 [R'=C9H6N-2, R=n-Pr (1), n-Bu (2); R'=4-OMe-C9H5N-2, R=n-Pr (3), n-Bu (4); R'=C9H6N-1, R=n-Pr (5), n-Bu (6)]. These have been characterized by FAB mass, IR, and multinuclear (1H, 13C, 119Sn) NMR spectral data and X-ray crystallography (for 4 and 6). The molecular structure of 4 (C20H29NO6SSn, monoclinic, P2(1)/n, a=14.1(13) A, b=16.7(18) A, c=20.3(19) A, beta=107(4) degrees, Z=8) comprises distorted octahedral geometry around each tin atom by virtue of weakly bridging methanesulfonate [Sn(1A)-O(3B)=3.010, Sn(1B)-O(3A)=2.984 A] and (N,O) chelation of the carboxylate ligands. The spectral data of 1-4 suggest a similar structural motif in solution. The molecular structure of 6 (C38H53N2O10S2Sn2, monoclinic, P2(1)/c, a=11.339(2) A, b=14.806(3) A, c=24.929(5) A, beta=100.537(3) degrees, Z=4) reveals varying bonding preferences with monomeric units being held together by a bridging methanesulfonate [Sn(2)-O(5)=2.312(2) A] and a carboxylate group bonded to Sn(1) and Sn(2) atoms, respectively. Slow hydrolysis of compound 2 derived from 2-quinoline carboxylic acid in moist CH3CN affords the asymmetric distannoxane, [Bu2Sn(O2CC9H6N-2)-O-Sn(OSO2Me)Bu2]2 (7) (C27H45NO6SSn2, monoclinic, C2/c, a=21.152(3) A, b=13.307(2) A, c=26.060(4) A, beta=110.02(10) degrees, Z=8) featuring ladder type structural motif by virtue of unique mu2-coordination of covalently bonded oxygen atoms [O(6), O(6)#1] of the methanesulfonate groups.     

Synthesis,characterization and crystal structures of 2-[(E)-2-(4-hydroxy-3,5-dimethylphenyl)-1-diazenyl]benzoic acid and its polymeric and monomeric triorganotin(IV) complexes

Three triorganotin(IV) complexes of composition R₃SnLH (R = Me, Bu and Ph and LH = 2-[(E)-2-(4-hydroxy-3,5-dimethylphenyl)-1-diazenyl]benzoate) have been synthesized and characterized by ¹H, ¹³C, ¹¹⁹Sn NMR, and IR spectroscopic techniques in combination with elemental analysis. The crystal structures of the carboxylate ligand HO₂CC₆H₄{NN(C₆H₂-4-OH-3,5-(CH₃)₂)}-o in its neutral form and three triorganotin(IV) complexes, viz., polymeric (R₃Sn[O₂CC₆H₄{N–N(H)(C₆H₂-4-O-3,5-(CH₃)₂)}-o])_n (R = Me (1) and Bu (2)) and monomeric Ph₃Sn[O₂CC₆H₄{N–N(H)(C₆H₂-4-O-3,5-(CH₃)₂)}-o] (3) complexes are reported. The polymeric complexes 1 and 2 exist as extended chains in which the LH-bridged Sn-atoms adopt a trans-R₃SnO₂ trigonal bipyramidal configuration with R groups in the equatorial positions and the axial sites occupied by an oxygen atom from the carboxylate ligand and the phenoxide O atom of the next carboxylate ligand. The Sn atom in complex 3 has a distorted tetrahedral geometry. In all three complexes, the carboxylate ligand is in the zwitterionic form with the phenolic proton moved to the nearby azo nitrogen atom, in contrast to the free carboxylic acid ligand which is in the azo form.     

Synthesis,characterization and crystal structures of 2-[(E)-2-(4-hydroxy-3,5-dimethylphenyl)-1-diazenyl]benzoic acid and its polymeric and monomeric triorganotin(IV) complexes

Three triorganotin(IV) complexes of composition R₃SnLH (R = Me, Bu and Ph and LH = 2-[(E)-2-(4-hydroxy-3,5-dimethylphenyl)-1-diazenyl]benzoate) have been synthesized and characterized by ¹H, ¹³C, ¹¹⁹Sn NMR, and IR spectroscopic techniques in combination with elemental analysis. The crystal structures of the carboxylate ligand HO₂CC₆H₄{NN(C₆H₂-4-OH-3,5-(CH₃)₂)}-o in its neutral form and three triorganotin(IV) complexes, viz., polymeric (R₃Sn[O₂CC₆H₄{N–N(H)(C₆H₂-4-O-3,5-(CH₃)₂)}-o])_n (R = Me (1) and Bu (2)) and monomeric Ph₃Sn[O₂CC₆H₄{N–N(H)(C₆H₂-4-O-3,5-(CH₃)₂)}-o] (3) complexes are reported. The polymeric complexes 1 and 2 exist as extended chains in which the LH-bridged Sn-atoms adopt a trans-R₃SnO₂ trigonal bipyramidal configuration with R groups in the equatorial positions and the axial sites occupied by an oxygen atom from the carboxylate ligand and the phenoxide O atom of the next carboxylate ligand. The Sn atom in complex 3 has a distorted tetrahedral geometry. In all three complexes, the carboxylate ligand is in the zwitterionic form with the phenolic proton moved to the nearby azo nitrogen atom, in contrast to the free carboxylic acid ligand which is in the azo form.     

Simplified synthesis, H, C, N, Sn NMR spectra and X-ray structures of diorganotin(IV) complexes containing the 4-phenyl-2,4-butanedionebenzoylhydrazone(2−) ligand

Two diorganotin(IV) complexes of the general formula R₂Sn[Ph(O)CCH-C(Me)N-NC(O)Ph] (R=Ph, 1; R=Me, 2) have been synthesised from the corresponding diorganotin(IV) dichloride and the ligand 4-phenyl-2,4-butanedionebenzoylhydrazone(2−) (H₂L), derived from benzoyl acetone and benzoyl hydrazide in methanol at room temperature in presence of triethylamine. The syntheses were performed under very mild conditions, at room temperature and without exclusion of air or moisture from the reaction vessel. Previously, rigorous conditions have been considered necessary for these species. The two compounds have been characterised by elemental analysis, IR and ¹H, ¹³C, ¹⁵N, ¹¹⁹Sn NMR spectra, and their structures have been confirmed single crystal X-ray structure analysis. The central tin atom of both complexes adopts a distorted trigonal bipyramidal coordination with two ligand oxygen atoms in axial positions, the nitrogen atom of the ligand and two organic groups on tin occupying equatorial sites. 2 has crystallised with two crystallographically independent molecules in the asymmetric unit. The δ(¹¹⁹Sn) values for the complexes 1 and 2 are −151.5 and −146.8 ppm, respectively, thus indicating penta-coordinated tin centres.     

New diorganotin(IV) derivatives of 7-hydroxycoumarin (umbelliferone) and their adducts with 1,10-phenanthroline

New diorganotin(IV) derivatives of the general formula R2Sn(Umb)2 (where R = n-Bu, n-Oct and Ph; Umb = umbelliferone anion) have been synthesized either by the reaction of R2SnO with umbelliferone under azeotropic removal of water or by the reaction of R2SnCl2 with sodium salt of umbelliferone. Further, the adducts of the general formula R2Sn(Umb)2.phen (where R = n-Bu and n-Oct; phen = 1,10-phenanthroline) have also been synthesized by the interaction of R2Sn(Umb)2 with 1,10-phenanthroline. The bonding and coordination behavior in these derivatives are discussed on the basis of IR and 119Sn M?ssbauer spectroscopic studies in solid state. Their coordination behavior in solution is discussed by the multinuclear (1H, 13C and 119Sn) NMR spectral studies. The M?ssbauer and IR studies indicate that umbelliferone acts as a monoanionic bidentate ligand in R2Sn(Umb)2 coordinating through O(7) and O(1). A distorted octahedral geometry around tin has been proposed for R2Sn(Umb)2 as well as for R2Sn(Umb)2.phen in solid state. The newly synthesized derivatives have been tested for their anti-inflammatory and cardiovascular activities. The average LD50 value >1000 mg kg(-1) of these compounds indicates their safety margin.     

Syntheses,characterizations, and crystal structures of tri‐ and diorganotin (IV) derivatives with 2‐mercapto‐5‐methyl‐1,3,4‐thiadiazole

A series of organotin(IV) complexes with 2‐mercapto‐5‐methyl‐1,3,4‐thiadiazole (HL) of the type R₃ Sn(L) (R = Me 1 ; Bu 2 ; Ph 3 ; PhCH₂ 4 ) and R₂Sn(L)₂ (R = CH₃ 5 ; Ph 6 ; PhCH₂ 7 ; Bu 8 ) have been synthesized. All complexes 1–8 were characterized by elemental analysis, IR,¹H, ¹³ C, and ¹¹⁹Sn NMR spectra. Among these, complexes 1 , 3 , 4 , and 7 were also determined by X‐ray crystallography. The tin atoms of complexes 1 , 3 , and 4 are all penta‐coordinated and the geometries at tin atoms of complexes 3 and 4 are distorted trigonal–bipyramidal. Interestingly, complex 1 has formed a 1D polymeric chain through Sn and N intermolecular interactions. The tin atom of complex 7 is hexa‐coordinated and its geometry is distorted octahedral. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:353–364, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20215     

Organotin(IV) derivatives as biocides: An investigation of structure by IR, solution NMR, electron impact MS and assessment of structure correlation with biocidal activity

A brief account is given of the synthesis, structural chemistry and the antibacterial, antifungal and cytotoxic effects of organotin complexes of 2-[(2,4-dichloroanilinocarbonyl)]benzoic acid. The unimolar and bimolar substitution products have been characterized by elemental analysis and spectral studies, including IR, ¹H NMR, ¹³C NMR, ¹¹⁹Sn NMR, and mass spectra. The data support the binding of the oxygen atom to the tin atom in [R₂Sn(OOCR’)₂] and [R₃Sn(OOCR’)] (R = Me, Bu, and Ph, R’ = 2-[(2,4-dichloroanilinocarbonyl)]benzoic acid). Based on these studies, with a coordination number of four, a distorted tetrahedral geometry has been proposed for the resulting derivatives in solution. The free ligand (R’/COOH) and its respective tin complexes were tested in vitro against a number of microorganisms to assess their biocidal properties and to correlate them with the structures of the derivatives.     

Synthesis,structural characterization and cytotoxic activity of triorganotin 5‐(salicylideneamino)salicylates

Six new triorganotin complexes ( 1a – 1c and 2a – 2c ) of 5‐(salicylideneamino)salicylic acid, [5‐(3‐X‐2‐HOC₆H₃CH═N)‐2‐HOC₆H₃COO]SnR₃ (X = H, 1 ; CH₃O, 2 ; R = Ph, a ; Cy, b ; CH₂C(CH₃)₂Ph, c ), have been synthesized by one‐pot reaction of 5‐aminosalicylic acid, salicylaldehyde and triorganotin hydroxide and characterized using elemental analysis and infrared and NMR (¹H, ¹³C and ¹¹⁹Sn) spectra. The crystal structures of 1a , 1b , 2a ·CH₃OH, 2b ·CH₃OH and 2c ·CHCl₃ have been determined using single‐crystal X‐ray diffraction. In non‐coordinated solvent CDCl₃, the tin atoms in the complexes are all four‐coordinated. In the crystalline state, these compounds adopt a four‐ or five‐coordination mode. Complex 1a exhibits a 44‐membered macrocyclic tetrameric structure with trigonal bipyramidal geometry around the tin atoms in which the axial positions are occupied by the oxygen atom of carboxylate group of the ligand and the phenolic oxygen atom from the adjacent ligand. The coordination geometry of tin atom in 1b and 2c ·CHCl₃ is a distorted tetrahedron shaped by three carbon atoms of alkyl groups and a carboxylate oxygen atom of the ligand. In 2a ·CH₃OH and 2b ·CH₃OH, the tin atom has a distorted trans‐C₃SnO₂ trigonal bipyramidal geometry formed by three alkyl groups, a monodentate carboxylate group and a coordinated methanol molecule. The molecules of 2a ·CH₃OH and 2b ·CH₃OH are linked via O─H···O hydrogen bonds into a one‐dimensional supramolecular chain and a centrosymmetric R₄⁴(22) macrocycle, respectively. Bioassay results against two human tumor cell types (A549 and HeLa) show the complexes are efficient cytostatic agents and may be explored as potential antitumor drugs.     

二{氧合-二[3-二茂铁基丙烯酸二正丁基锡(Ⅳ)]} 配合物的晶体结构及溶液中的 配位互变平衡机理

测定了配合物{[(n-Bu)2Sn(FcCH=CHCO2)]2O}2(Fc=Ferrocenyl)晶体结构,它属三斜晶系,空间群P1,晶胞参数a=1.3943(3)nm,b=1.4635(3)m,c=1.2792(3)nm,α=94.32(3)°,β=116.27(3)°,γ=109.08(3)°,Z=2,V=2.1362(8)nm^3,Dc=1.542g/cm^3,F(000)=1004。最终偏差因子R=0.0401,Rw=0.1076。该分子中存在着内环锡和外环锡配位单元,锡原子均形成具有假六配位的单加帽畸变三角双锥配位构型。Sn2O2中心内环与丙烯酸酯基茂环等共轭体系之间相互未能共平面。配合物中四个羧基配体划分为两类：两个为桥式双齿配位(μ-COO),跨接于一个内环锡和一个外环锡;另两个仅以单齿配位方式各连接一个外环锡。根据核磁共振谱信息表明分子在溶液中存在着配位互变异构体之间的快交换。我们提出振动模式的假说,认为可能是羧酸酯基氧在其平面内快速摇摆建立了动态平衡之故。     

二聚体有机锡配合物{[n-Bu2Sn(O2CCH2CS2NC4H8)]2O}2的合成，表征及晶体结构(英)

The title compound, {[n-Bu₂Sn(O₂CCH₂CS₂NC₄H₈)]₂O}₂, has been synthesized by the reaction of (tetrahydro-pyrrodithiolocarbamoylthio)acetic acid with the di-n-bubyltin oxide in 1∶1 molar ratio. The complex has been characterized by elemental analysis, IR and NMR. The crystal structure of it has been determined by X-ray single crystal diffraction. And the results showed that the crystal belongs to triclinic system with space group P1 and some crystal parameters: a=1.220 2(9) nm, b=1.315 8(10) nm, c=1.380 4(10) nm, α=111.215(9)°， β=99.357(9)°， γ=96.075(10)°, V=2.006(2) nm³, Z=1, F(000)=908, μ=1.489 mm^-1, D_c=1.474 g·cm^-3, R₁=0.037 5, wR₂=0.0839. The complex has a centrosymmetric dimer structure mode with a four-membered central endo-cyclic Sn₂O₂ unit in which two bridged oxygen atoms both connect with an exo-cyclic tin atom which has a distorted octahedron. Each of the endo-cyclic tin atoms exhibits a distorted trigonal bipyramid coordination geometry with an additional weak coordination carboxylate oxygen. Four carboxylate ligands are divided into two types. And two of them are bidentate and connecting to each of exo-cyclic tin atoms by using both oxygen atoms, whereas the others bridge to each pair of exo-and endo-cyclic tin atoms utilizing one oxygen atom only. CCDC: 220513.     

Organotin(IV) complexes derived from proteinogenic amino acid: synthesis,structure and evaluation of larvicidal efficacy on Anopheles stephensi mosquito larvae

Five new organotin(IV) complexes of composition [Bz₂SnL¹]_n ( 1 ), [Bz₃SnL¹H⋅H₂O] ( 2 ), [Me₂SnL²⋅H₂O] ( 3 ), [Me₂SnL³] ( 4 ) and [Bz₃SnL³H]_n ( 5 ) (where L¹ = (2S )‐2‐{[(E )‐(4‐hydroxypentan‐2‐ylidene)]amino}‐4‐methylpentanoate, L² = (rac )‐2‐{[(E )‐1‐(2‐hydroxyphenyl)methylidene]amino}‐4‐methylpentanoate and L³ = (2S )‐ or (rac )‐2‐{[(E )‐1‐(2‐hydroxyphenyl)ethylidene]amino}‐4‐methylpentanoate) were synthesized and characterized using ¹H NMR, ¹³C NMR, ¹¹⁹Sn NMR and infrared spectroscopic techniques. The crystal structure of 2 reveals a distorted trigonal‐bipyramidal geometry around the tin atom where the oxygen atoms of the carboxylate ligand and a water ligand occupy the axial positions, while the three benzyl ligands are located at the equatorial positions. On the other hand, the analogous derivative of enantiopure L³H ( 5 ) consists of polymeric chains, in which the ligand‐bridged tin atoms adopt the same trans ‐Bz₃SnO₂ trigonal‐bipyramidal configuration and are now coordinated to a phenolic oxygen atom instead of H₂O. In 2 , the OH hydrogen of the ketoimine substituent has moved to the nearby nitrogen atom while in the salicylidene derivative 5 , the OH is located almost midway between the phenolic oxygen atom and the nitrogen atom of the CN group. For the dibenzyltin derivative 1 , a polymeric chain structure is observed as a result of a long intermolecular Sn⋅⋅⋅O bond involving the exocyclic carbonyl oxygen atom from the tridentate ligand of a neighbouring tin‐complex unit. The tin atom in this complex has distorted octahedral coordination geometry. In contrast, the racemic dimethyltin(IV) complexes 3 and 4 display discrete monomeric structures with a distorted octahedral‐ and trigonal‐bipyramidal geometry, respectively. The structures show that the coordination mode of the Schiff base ligand depends primarily on the number of bulky benzyl ligands (R) at the tin atom, as indeed found in the structures of related complexes where R = phenyl. With three bulky R groups, the tridentate chelating O,N,O coordination mode is preferred, whereas with fewer or less bulky R ligands, only the carboxylate and hydroxy groups are involved, which leads to polymers. Larvicidal efficacies of two of the new tribenzyltin(IV) complexes ( 2 and 5 ) were assessed on the second larval instar of Anopheles stephensi mosquito larvae and compared with two triphenyltin(IV) analogues, [Ph₃SnL¹H]_n and [Ph₃SnL³H]_n . The results demonstrate that the compounds containing Sn–Ph ligands are more effective than those with Sn–Bz ligands. Copyright © 2016 John Wiley & Sons, Ltd.     

Synthesis,structural characterization,and properties of triorganotin complexes of Schiff base derived from 3-aminobenzoic acid and salicylaldehyde or 2,4-pentanedione

Six new triorganotin 3-(salicylideneamino)benzoates ( 1a – 1c ) and 3-(4-oxo-2-penten-2-ylamino)benzoates ( 2a – 2c ), 3-(2-HOC₆H₄CH=N)C₆H₄COOSnR₃, and 3-(CH₃COCH=C(CH₃)NH)C₆H₄COOSnR₃ (R = Ph, a ; Cy, b ; Bu, c ) have been synthesized by one-pot reaction of 3-aminobenzoic acid, salicylaldehyde (or 2,4-pentanedione), and triorganotin hydroxide and characterized by elemental analysis, infrared, and nuclear magnetic resonance (¹H, ¹³C, and ¹¹⁹Sn) spectra. The crystal structures of 1a , 1b , and 2a – 2c have been determined by the single crystal X-ray diffraction. Complexes 1a and 2a exhibit a 44-membered macrocyclic tetramer and a polymeric zigzag chain, respectively, in which tin atoms show trans-[C₃SnO₂] trigonal bipyramidal geometry with the axial positions being occupied by the carboxylate oxygen atom and the phenolic (or ketone) oxygen atom from another ligand. Complex 1b adopts a distorted tetrahedral geometry at tin, and there are two molecules differing in the relative orientation of the carboxylate toward the imino group. Compounds 2a ⋅CH₃OH, 2b ⋅H₂O, and 2c ⋅H₂O are five-coordinated mononuclear adducts with one coordinated solvent molecule and display different supramolecular organizations in which there are the centrosymmetric R₂²(16), R₄²(22), and R₆⁴(34) macrocycle motifs formed by the O–H⋅⋅⋅O, N–H⋅⋅⋅O, and C–H⋅⋅⋅O hydrogen bonds. The fluorescence spectrum indicates that the complexes may be explored for potential blue luminescent materials. Compared to cisplatin, these compounds exhibit enhanced cytotoxic efficacy and can be considered as anticancer agents for further study.     

Synthesis,structure, and fungicidal activity of triorganotin (4H‐1,2,4‐triazol‐4‐yl)benzoates

A series of triorganotin (4H‐1,2,4‐triazol‐4‐yl)benzoates have been synthesized by the reaction of 4‐(4H‐1,2,4‐triazol‐4‐yl)benzoic acid and 3‐(4H‐1,2,4‐triazol‐4‐yl)benzoic acid with (R₃Sn)₂O (R = Et, n‐Bu and Ph) or R′₃SnOH (R′ = p‐tolyl and cyclohexyl). The molecular structure of tri(p‐tolyl)tin 3‐(4H‐1,2,4‐triazol‐4‐yl)benzoate determined by X‐ray crystallography displays that the tin atom adopts a five‐coordinate distorted trigonal bipyramidal geometry with the carboxyl oxygen atom and the nitrogen atom on 1‐position of triazole ring occupying the apical position. Moreover, this complex forms a polymeric chain by the intermolecular Sn–N interactions. All these complexes show good antifungal activities in vitro against Alternaria solani, Cercospora arachidicola, Gibberella zeae, Physalospora piricola, and Botrytis cinerea. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 20:411–417, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20566     

Hydrothermal syntheses, characterizations and crystal structures of a new lead(II) carboxylate-phosphonate with a double layer structure and a new nickel(II) carboxylate-phosphonate containing a hydrogen-bonded 2D layer with intercalation of ethylenediamines

Hydrothermal reactions of N,N-bis(phosphonomethyl)aminoacetic acid (HO₂CCH₂N(CH₂PO₃H₂)₂) with metal(II) salts afforded two new metal carboxylate-phosphonates, namely, Pb₂[O₂CCH₂N(CH₂PO₃)(CH₂PO₃H)]·H₂O (1) and {NH₃CH₂CH₂NH₃}{Ni[O₂CCH₂N(CH₂PO₃H)₂](H₂O)₂}₂ (2). Among two unique lead(II) ions in the asymmetric unit of complex 1, one is five coordinated by five phosphonate oxygen atoms from 5 ligands, whereas the other one is five-coordinated by a tridentate chelating ligand (1 N and 2 phosphonate O atoms) and two phosphonate oxygen atoms from two other ligands. The carboxylate group of the ligand remains non-coordinated. The bridging of above two types of lead(II) ions through phosphonate groups resulted in a 〈002〉 double layer with the carboxylate group of the ligand as a pendant group. These double layers are further interlinked via hydrogen bonds between the carboxylate groups into a 3D network. The nickel(II) ion in complex 2 is octahedrally coordinated by a tetradentate chelating ligand (two phosphonate oxygen atoms, one nitrogen and one carboxylate oxygen atoms) and two aqua ligands. These {Ni[O₂CCH₂N(CH₂PO₃H)₂][H₂O]₂}⁻ anions are further interlinked via hydrogen bonds between non-coordinated phosphonate oxygen atoms to form a 〈800〉 hydrogen bonded 2D layer. The 2H-protonated ethylenediamine cations are intercalated between two layers, forming hydrogen bonds with the non-coordinated carboxylate oxygen atoms. Results of magnetic measurements for complex 2 indicate that there is weak Curie-Weiss behavior with θ=−4.4 K indicating predominant antiferromagnetic interaction between the Ni(II) ions. Indication for magnetic low-dimension magnetism could not be detected.     

Organotin(IV) derivatives of mercaptosuccinic and thiodiacetic acids

Di- and tri-organotin(IV) complexes of general formula R₂SnAH, (R₃Sn)₂AH, R₂SnB, (R₃Sn)₂B (A=dianion of mercaptosuccinic acid; B=dianion of thiodiacetic acid; R=Me, Et, nPr, nBu, nOct in R₂Sn and nBu in R₃Sn) have been synthesized and characterized by elemental analysis, IR and ¹H and ¹³C NMR spectroscopy. These data support the preferential binding of sulphur over carboxylate by tin(IV) in R₂SnAH and (R₃Sn)₂AH. R₂SnAH complexes are assigned pentacoordinated bridged polymeric trigonal bipyramidal geometry whereas (R₃Sn)₂AH complexes are monomeric with trigonal bipyramidal geometry at tin arising from a bidentate carboxylate group at one tin atom and from weak bonding via Sn←O?C at the other tin atom. In R₂SnB and (R₃Sn)₂B, tin(IV) binds to two carboxylate groups in a unidentate and a bidentate manner respectively, resulting in tetracoordinated and pentacoordinated structures. Potential uses of these compounds are discussed.     

Synthesis,molecular structure and stereoisomerization of 2-phosphinyl and 2-phosphonylethyl diorganotin halides

Functionally substituted triorganotin halides V–IX of type R₂Sn(X)(CH₂)₂P(O)PhR′ (R = Me, t-Bu; Rt? = OEt, t-Bu; X = Cl, Br) have been synthesized by halogen cleavage of the corresponding tetraorganotin compounds R₂R²Sn(CH₂)₂P(O)PhR′ (R² = Me or Ph), I–IV. The solid state structure of Me₂Sn (Br) (CH₂)₂P(O)PhBu-t (IX), determined by X-ray diffraction, shows a distorted trigonal-bipyramidal structure at the tin atom, with intramolecular coordination of the PO group. Spectroscopic data are in agreement with such a structure in solution for compounds V–IX. Upon varying the temperature, concentration or solvent in solutions of compounds V–IX a stereoisomerization is observed. On the basis of NMR ¹H, ¹³C, ³¹P, ¹¹⁹Sn), IR and conductivity studies, it is suggested that this stereoisomerization involves a hexacoordinated transition state at the tin atom.