The synthesis,NMR (1H, 13C, 119Sn) and IR spectral studies of some di‐ and tri‐organotin(IV) sulfonates: X‐ray crystal structure of [(n‐C4H9)2Sn(OSO2C6H4CH3‐4)2·2H2O]

A number of alkyltin(IV) paratoluenesulfonates, R_nSn(OSO₂C₆H₄CH₃‐4)_4?n (n = 2, 3; R = C₂H₅, n‐C₃H₇, n‐C₄H₉), have been prepared and IR spectra and solution NMR (¹H, ¹³C, ¹¹⁹Sn) are reported for these compounds, including (n‐C₄H₉)₂Sn(OSO₂X)₂ (X = CH₃ and CF₃), the NMR spectra of which have not been reported previously. From the chemical shift δ(¹¹⁹Sn) and the coupling constants ¹J(¹³C, ¹¹⁹Sn) and ²J(¹H, ¹¹⁹Sn), the coordination of the tin atom and the geometry of its coordination sphere in solutions of these compounds is suggested. IR spectra of the compounds are very similar to that observed for the paratoluenesulfonate anion in its sodium salt. The studies indicate that diorganotin(IV) paratoluenesulfonates, and the previously reported compounds (n‐C₄H₉)₂Sn(OSO₂X)₂ (X = CH₃ and CF₃), contain bridging SO₃X groups that yield polymeric structures with hexacoordination around tin and contain non‐linear C? Sn? C bonds. In triorganotin(IV) sulfonates, pentacoordination for tin with a planar SnC₃ skeleton and bidentate bridging paratoluenesulfonate anionic groups are suggested by IR and NMR spectral studies. The X‐ray structure shows [(n‐C₄H₉)₂Sn(OSO₂C₆H₄CH₃‐4)₂·2H₂O] to be monomeric containing six‐coordinate tin and crystallizes from methanol–chloroform in monoclinic space group C2/c. The Sn? O (paratoluenesulfonate) bond distance (2.26(2) Å) is indicative of a relatively high degree of ionic character in the metal–anion bonds. Copyright © 2003 John Wiley & Sons, Ltd.     

Synthesis,spectral and antimicrobial studies of diorganotin(IV)3(2′‐hydroxyphenyl)‐5‐(4‐substituted phenyl) pyrazolinates

Diorganotin(IV) dipyrazolinates of the type R₂Sn(C₁₅H₁₂N₂OX)₂ [where C₁₅H₁₂N₂OX = 3(2′‐Hydroxyphenyl)‐5(4‐X‐phenyl)pyrazoline {where X = H ( a ); CH₃ ( b ); OCH₃ ( c ); Cl ( d ) and R = Me, Prⁿ and Ph}] have been synthesized by the reaction of R₂SnCl₂ with sodium salt of pyrazolines in 1:2 molar ratio, in anhydrous benzene. These newly synthesized derivatives have been characterized by elemental analysis (C, H, N, Cl and Sn), molecular weight measurement as well as spectral [IR and multinuclear NMR (¹H, ¹³C and ¹¹⁹Sn)] studies. The bidentate behaviour of the pyrazoline ligands was confirmed by IR, ¹H and ¹³C NMR spectral data. A distorted trans‐octahedral structure around tin(IV) atom for R₂Sn(C₁₅H₁₂N₂OX)₂ has been suggested. The free pyrazoline and diorganotin(IV) dipyrazolinates have also been screened for their antibacterial and antifungal activities. Some diorganotin(IV) dipyrazolinates exhibit higher antibacterial and antifungal effect than free ligand and some of the antibiotics. Copyright © 2006 John Wiley & Sons, Ltd.     

Synthesis,characterization, and biological studies of tri‐ and diorganotin(IV) complexes with 2′,4′‐difluoro‐4‐hydroxy‐[1,1′]‐biphenyle‐3‐carbolic acid: Crystal structure of [(CH3)3Sn(C13H7O3F2)]

Eight tri‐ and diorganotin(IV) carboxylates with general formulae R₃SnL and R₂SnL₂ (where R = CH₃, n‐C₄H₉, C₆H₅, C₇H₇, and L = 2′,4′‐difluoro‐4‐hydroxy‐[1,1′]‐biphenyl‐3‐carboxylic acid) were synthesized and characterized by UV–vis, IR, conductance, multinuclear (¹H, ¹³C, and ¹¹⁹Sn) NMR spectroscopy, and mass spectrometry. The crystal structure of [(CH₃)₃Sn(C₁₃H₇O₃F₂)] indicates that the tin atom in the asymmetric unit exists in a trigonal bipyramidal geometry having a space group Pbca with an orthorhombic crystal system. These complexes were also screened for their antibacterial and antifungal activities. © 2002 Wiley Periodicals, Inc. Heteroatom Chem 13:638–649, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10057     

Ecofriendly synthesis,antimicrobial and antispermatogenic activity of triorganotin(IV) complexes with 4′‐nitrobenzanilide semicarbazone and 4′‐nitrobezanilide thiosemicarbazone

New series of triorganotin(IV) complexes with 4′‐nitrobenzanilide semicarbazone (L¹H) and 4′‐nitrobenzanilide thiosemicarbazone (L²H) of the type [R₃Sn(L)] (R = ‐CH₃, ‐C₆H₅ and n‐C₄H₉) were synthesized under microwave irradiation. All the complexes were characterized by elemental analysis, conductance measurements, molecular weight determinations and spectral data, viz., IR, UV–vis, ¹H, ¹³C and ¹¹⁹Sn NMR. The central tin atoms of these complexes are all five‐coordinated with trigonal bipyramidal geometry. In order to assess their growth inhibitory potency semicarbazone, thiosemicarbazone and their triorganotin(IV) complexes were tested in vitro against some pathogenic fungi and bacteria. Also the ligands and their organotin(IV) complexes were studied to assess the effects of long‐term ingestion of these compounds on fertility, body and reproductive organ weights. The biochemical analyses were also performed on blood samples and reproductive organs of male rats. The findings have been presented in this paper. Copyright © 2009 John Wiley & Sons, Ltd.     

Synthesis, Characterization and Biological Activity of Diorganotin（IV） Complexes of N-（3,5-Dibromosalicylidene）-α-amino Acid

The diorganotin（Ⅳ） complexes of N-（3,5-dibromosalicylidene）-α-amino acid, R2Sn（2-O-3,5-Br2C6H2CH= NCHRCOO）（where R=H, Me, i-Pr, Bz; R＇=n-Bu, Cy）, were synthesized by the reactions of diorganotin dichlorides with in situ formed potassium salt of N-（3,5-dibromosalicylidene）-α-amino acid and characterized by elemental analysis, IR and NMR （^1H, ^13C and ^119Sn） spectra. The crystal structures of n-Bu2Sn（2-O-3,5-Br2C6H2CH= NCHRCOO）（R=i-Pr, Bz） and Cy2Sn（2-O-3,5-Br2C6H2CH=NCHRCOO）（R=Me, Bz） were determined by X-ray single crystal diffraction and showed that the tin atoms are in a distorted trigonal bipyramidal geometry to form five- and six-membered chelate rings with the tridentate ligand. Bioassay results indicated that the compounds possess better in vitro antitumour activity against three human tumour cell lines, HeLa, CoLo205 and MCF-7, than cis-platin and moderate anti-bacterial activity against two bacteria, E. coli and S. aureus.     

Synthesis and characterization of di‐n‐butyltin(IV) complexes with 4′/2′‐nitrobiphenyl‐2‐carboxylic acids: X‐ray crystal structures of [{(n‐C4H9)2Sn(OCOC12H8NO2−4′)}2O]2 and (n‐C4H9)2Sn{OCOC12H8NO2−4′}2

Reactions of di‐n‐butyltin(IV) oxide with 4′/2′‐nitrobiphenyl‐2‐carboxylic acids in 1 : 1 and 1 : 2 stoichiometry yield complexes [{(n‐C₄H₉)₂Sn(OCOC₁₂H₈NO₂?4′/2′)}₂O]₂ ( 1 and 2 ) and (n‐C₄H₉)₂Sn(OCOC₁₂H₈NO₂?4′/2′)₂ ( 3 and 4 ) respectively. These compounds were characterized by elemental analysis, IR and NMR (¹H, ¹³C and ¹¹⁹Sn) spectroscopy. The IR spectra of these compounds indicate the presence of anisobidentate carboxylate groups and non‐linear C? Sn? C bonds. From the chemical shifts δ (¹¹⁹Sn) and the coupling constants ¹J(¹³C, ¹¹⁹Sn), the coordination number of the tin atom and the geometry of its coordination sphere have been suggested. [{(n‐C₄H₉)₂Sn(OCOC₁₂H₈NO₂?4′)}₂O]₂ ( 1 ) exhibits a dimeric structure containing distannoxane units with two types of tin atom with essentially identical geometry. To a first approximation, the tin atoms appear to be pentacoordinated with distorted trigonal bipyramidal geometry. However, each type of tin atom is further subjected to a sixth weaker interaction and may be described as having a capped trigonal bipyramidal structure. The diffraction study of the complex (n‐C₄H₉)₂Sn(OCOC₁₂H₈NO₂?4′)₂ ( 3 ) shows a six–coordinate tin in a distorted octahedral frame containing bidentate asymmetric chelating carboxylate groups, with the n‐Bu groups trans to each other. The n‐Bu? Sn? n‐Bu angle is 152.8° and the Sn? O distances are 2.108(4) and 2.493(5) Å. The oxygen atom of the nitro group of the ligand does not participate in bonding to the tin atom in 1 and 3 . Crystals of 1 are triclinic with space group P1 and of that of 3 have orthorhombic space group Pnna. Copyright © 2003 John Wiley & Sons, Ltd.     

Synthesis and Crystal Structure of Di-n-butyltin（Ⅳ） Complex with 2-Oxo-propionic Acid （4-Pyridinecarbonyl） Hydrazone

The novel complex di‐n‐butyltin(IV) 2‐oxo‐propionic acid (4‐pyridinecarbonyl) hydrazone, (n‐C₄H₉)₂Sn‐[O₂CC(CH₃)=N‐N=C(‐O)C₅N‐4] (H₂O) has been synthesized and its structure has been determined by X‐ray diffraction analysis. The complex crystallizes in orthorhombic system with space group Pca2₁. Crystal data: a=2.7540(9) nm, b=0.9676(3) nm, c= 1.5750(5) nm, V=4.197(2) nm³, D_c= 1.444 g/cm³, Z=8. μ= 1.241 mm^?1. F(000)= 1856, R₁=0.0462 and wR₂=0.1001. In the crystals of the title complex, the tin atom is in six‐coordination with a distorted octahedral geometry, three oxygen atoms [O(1), O(3) and O(4)] and one nitrogen atom N(1) forming the equatorial plane and C(10)‐Sn(1)‐C(14) being the axis. Two molecules form a dimer with weak interactions of Sn‐O bonding and hydrogen bonds.     

Self‐Assembly of Dialkyltin Moieties and Mercaptobenzoic Acid into Macrocyclic Complexes with Hydrophobic “Pseudo‐Cage” or Double‐Cavity Structures: Supramolecular Infrastructures Involving Intermolecular C?H⋅⋅⋅S Weak Hydrogen Bonds and π–π Interactions

Four novel organotin complexes of two types—[R₂Sn(o‐SC₆H₄CO₂)]₆ (R=Me, 1 ?H₂O; nBu, 2 ) and {[R₂Sn(m‐CO₂C₆H₄S)R₂Sn(m‐SC₆H₄CO₂)SnR₂]O}₂ (R=Me, 3 ; nBu, 4 )—have been prepared by treatment of o‐ or m‐mercaptobenzoic acid and the corresponding R₂SnCl₂ (R=Me, nBu) with sodium ethoxide in ethanol (95 %). All the complexes were characterized by elemental analysis, FT‐IR and NMR (¹H, ¹³C, ¹¹⁹Sn) spectroscopy, TGA, and X‐ray crystallography diffraction analysis. The molecular structure analyses reveal that both 1 and 2 are hexanuclear macrocycles with hydrophobic “pseudo‐cage” structures, while 3 and 4 are hexanuclear macrocycles with double‐cavity structures. Furthermore, the supramolecular structure analyses show that looser and more intriguing supramolecular infrastructures were also found in complexes 1 – 4 , which exist either as one‐dimensional chains of rings or as two‐dimensional networks assembled from the organometallic subunits through intermolecular C? H???S weak hydrogen bonds (WHBs) and π–π interactions.     

Tin(IV) and organotin(IV) derivatives of novel β-diketones: Part IV. Triorganotin(IV) complexes of fluorinated 4-acyl-5-pyrazolones. Crystal structure of (1-(4-trifluoromethylphenyl)-3-methyl-4-acetylpyrazolon-5-ato)triphenyltin(IV)

The synthesis of three 1-(4-trifluoromethylphenyl)-3-methyl-4-R¹(C=O)-5-pyrazolone proligands LH (L¹H; R¹=C₆H₅: L²H; R¹=CH₃: L³H; R¹=CF₃) and their interaction with R₃Sn(IV) acceptors (R=Me, Buⁿ, Ph) are reported. When R=Me or Buⁿ, aquo (4-acylpyrazolonate)SnR₃(H₂O) derivatives are obtained and the anionic donors 4-acylpyrazolonate (L⁻) act in the O–monodentate form. These triorganotin complexes are not stable in chlorohydrocarbon solvents and decompose to R₄Sn and bis(4-acyl-5-pyrazolonate)₂SnR₂. When R=Ph, stable (4-acyl-5-pyrazolonate)SnPh₃ derivatives, both in solution and in the solid state, are obtained. The crystal structure of (1-(4-trifluoromethylphenyl)-3-methyl-4-acetylpyrazolon-5-ato)triphenyltin(IV) shows a five-coordinate tin atom in a strongly distorted cis-bipyramidal trigonal environment (axial angle=161.2(2)°) with the acylpyrazolonate donor acting as an asymmetric O₂–bidentate species (Sn–O(1)=2.081(6) Å: Sn–O(2)=2.424(5) Å). Electronic effects are responsible for the different behavior shown by these trialkyl and triphenyl derivatives.     

π–π stacking motifs in dialkylbis{5‐[(E)‐2‐aryldiazen‐1‐yl]‐2‐hydroxybenzoato}tin(IV) complexes

The diorganotin(IV) complexes of 5‐[(E)‐2‐aryldiazen‐1‐yl]‐2‐hydroxybenzoic acid are of interest because of their structural diversity in the crystalline state and their interesting biological activity. The structures of dimethylbis{2‐hydroxy‐5‐[(E)‐2‐(4‐methylphenyl)diazen‐1‐yl]benzoato}tin(IV), [Sn(CH₃)₂(C₁₄H₁₁N₂O₃)₂], and di‐n‐butylbis{2‐hydroxy‐5‐[(E)‐2‐(4‐methylphenyl)diazen‐1‐yl]benzoato}tin(IV) benzene hemisolvate, [Sn(C₄H₉)₂(C₁₄H₁₁N₂O₃)₂]·0.5C₆H₆, exhibit the usual skew‐trapezoidal bipyramidal coordination geometry observed for related complexes of this class. Each structure has two independent molecules of the Sn^IV complex in the asymmetric unit. In the dimethyltin structure, intermolecular O—H…O hydrogen bonds and a very weak Sn…O interaction link the independent molecules into dimers. The planar carboxylate ligands lend themselves to π–π stacking interactions and the diversity of supramolecular structural motifs formed by these interactions has been examined in detail for these two structures and four closely related analogues. While there are some recurring basic motifs amongst the observed stacking arrangements, such as dimers and step‐like chains, variations through longitudinal slipping and inversion of the direction of the overlay add complexity. The π–π stacking motifs in the two title complexes are combinations of some of those observed in the other structures and are the most complex of the structures examined.     

Synthesis,structural characterization and cytotoxic activity of diorganotin(IV) complexes of N‐(5‐halosalicylidene)‐α‐amino acid

Fourteen new diorganotin(IV) complexes of N‐(5‐halosalicylidene)‐α‐amino acid, R′₂Sn(5‐X‐2‐OC₆H₃CH?NCHRCOO) (where X = Cl, Br; R = H, Me, i‐Pr; R′ = n‐Bu, Ph, Cy), were synthesized by the reactions of diorganotin halides with potassium salt of N‐(5‐halosalicylidene)‐α‐amino acid and characterized by elemental analysis, IR and NMR (¹H, ¹³C and ¹¹⁹Sn) spectra. The crystal structures of Bu₂Sn(5‐Cl‐2‐OC₆H₃CH?NCH(i‐Pr)COO) and Ph₂Sn(5‐Br‐2‐OC₆H₃CH?NCH(i‐Pr)COO) were determined by X‐ray single‐crystal diffraction and showed that the tin atoms are in a distorted trigonal bipyramidal geometry and form five‐ and six‐membered chelate rings with the tridentate ligand. Bioassay results of a few compounds indicated that the compounds have strong cytotoxic activity against three human tumour cell lines, i.e. HeLa, CoLo205 and MCF‐7, and the activity decreased in the order Cy>n‐Bu>Ph for the R′ group bound to tin. Copyright © 2005 John Wiley & Sons, Ltd.     

{nBuMg(OR)}2 und {Mg(OR)2}2 (R = 2, 4, 6‐tBu3C6H2) – sterisch überfrachtete Magnesiumalkoholate

Reaction of 2, 4, 6‐tri‐tert‐butylphenol ( 1 ) with di‐n‐butylmagnesium in the molar ratio 1:1 allows the synthesis of {(nBu)Mg(μ‐OR)₂Mg(nBu)} ( 2 ) (R = 2, 4, 6‐tBu₃C₆H₂), which reacts with excess 1 to give the homoleptic alcoholate complex {(RO)Mg(μ‐OR)₂Mg(OR)} ( 3 ) (R = 2, 4, 6‐tBu₃C₆H₂). The structures of 2 and 3 were determined by X‐ray crystallography.     

Synthesis,structural characterization and cytotoxic activity of diorganotin(IV) complexes of N‐(5‐halosalicylidene)tryptophane

Four new diorganotin(IV) complexes of N‐(5‐halosalicylidene)tryptophane, R₂Sn[5‐X‐2‐OC₆H₃CH?NCH(CH₂Ind)COO] [Ind = 3‐indolyl; R, X = Et, Cl ( 1 ); Et, Br( 2 ); n‐Bu, Cl ( 3 ); n‐Bu, Br ( 4 )], were synthesized and characterized by elemental analysis, IR and NMR (¹H, ¹³C and ¹¹⁹Sn) spectra. The crystal structures of complexes 1 – 3 were determined by X‐ray single crystal diffraction and showed that the tin atoms are in a distorted trigonal bipyramidal geometry and form five‐ and six‐membered chelate rings with the tridentate ligand. Intermolecular weak interactions in 1–3 link molecules, respectively, into a two‐dimensional array, a one‐dimensional infinite chain and a one‐dimensional double‐chain supramolecular structure. Bioassay results of the compounds indicated that the dibutyltin complexes 3 and 4 have potent in vitro cytotoxic activity against two human tumor cell lines, CoLo205 and Bcap37, while the diethyltin complexes 1 and 2 display weak cytotoxic activity. Copyright © 2008 John Wiley & Sons, Ltd.     

Metabolism of Deuterated Isomeric 6,7‐Dihydroxydodecanoic Acids in Saccharomyces cerevisiae – Diastereo‐ and Enantioselective Formation and Characterization of 5‐Hydroxydecano‐4‐lactone (=4,5‐Dihydro‐5‐(1‐hydroxyhexyl)furan‐2(3H)‐one) Isomers

The chemical synthesis of deuterated isomeric 6,7‐dihydroxydodecanoic acid methyl esters 1 and the subsequent metabolism of esters 1 and the corresponding acids 1a in liquid cultures of the yeast Saccharomyces cerevisiae was investigated. Incubation experiments with (6R,7R)‐ or (6S,7S)‐6,7‐dihydroxy(6,7‐²H₂)dodecanoic acid methyl ester ((6R,7R)‐ or (6S,7S)‐(6,7‐²H₂)‐ 1 , resp.) and (±)‐threo‐ or (±)‐erythro‐6,7‐dihydroxy(6,7‐²H₂)dodecanoic acid ((±)‐threo‐ or (±)‐erythro‐(6,7‐²H₂)‐ 1a , resp.) elucidated their metabolic pathway in yeast (Tables 1–3). The main products were isomeric ²H‐labeled 5‐hydroxydecano‐4‐lactones 2 . The absolute configuration of the four isomeric lactones 2 was assigned by chemical synthesis via Sharpless asymmetric dihydroxylation and chiral gas chromatography (Lipodex ^® E). The enantiomers of threo‐ 2 were separated without derivatization on Lipodex ^® E; in contrast, the enantiomers of erythro‐ 2 could be separated only after transformation to their 5‐O‐(trifluoroacetyl) derivatives. Biotransformation of the methyl ester (6R,7R)‐(6,7‐²H₂)‐ 1 led to (4R,5R)‐ and (4S,5R)‐(2,5‐²H₂)‐ 2 (ratio ca. 4 : 1; Table 2). Estimation of the label content and position of (4S,5R)‐(2,5‐²H₂)‐ 2 showed 95% label at C(5), 68% label at C(2), and no ²H at C(4) (Table 2). Therefore, oxidation and subsequent reduction with inversion at C(4) of 4,5‐dihydroxydecanoic acid and transfer of ²H from C(4) to C(2) is postulated. The 5‐hydroxydecano‐4‐lactones 2 are of biochemical importance: during the fermentation of Streptomyces griseus, (4S,5R)‐ 2 , known as L‐factor, occurs temporarily before the antibiotic production, and (?)‐muricatacin (=(4R,5R)‐5‐hydroxy‐heptadecano‐4‐lactone), a homologue of (4R,5R)‐ 2 , is an anticancer agent.     

A pair of diastereomeric 1:1 salts of (S)‐ and (R)‐2‐methylpiperazine with (2S,3S)‐tartaric acid

The structures of diastereomeric pairs consisting of (S)‐ and (R)‐2‐methylpiperazine with (2S,3S)‐tartaric acid are both 1:1 salts, namely (S)‐2‐methylpiperazinium (2S,3S)‐tartrate dihydrate, C₅H₁₄N₂²⁺·C₄H₄O₆²⁻·2H₂O, (I), and (R)‐2‐methylpiperazinium (2S,3S)‐tartrate dihydrate, C₅H₁₄N₂²⁺·C₄H₄O₆²⁻·2H₂O, (II), which reveal the formation of well defined ammonium carboxylate salts linked via strong intermolecular hydrogen bonds. Unlike the situation in the more soluble salt (II), the alternating columns of tartrate and ammonium ions of the less soluble salt (I) are packed neatly in a grid around the a axis, which incorporates water molecules at regular intervals. The increased efficiency of packing for (I) is evident in its lower `packing coefficient', and the hydrogen‐bond contribution is stronger in the more soluble salt (II).     

Syntheses,characterizations, and crystal structures of organotin(IV) chloride complexes with 4,4′‐bipyridine

The organotin(IV) chlorides R_nSnCl_4−n (n = 3, R = Ph, PhCH₂, n−Bu; and n =2, R = n−Bu, Ph, PhCH₂) react with 4,4′‐bipyridine (4′4‐bpy) to give [(Ph₃SnCl)₂(4,4′‐bpy)_1.5(C₆H₆)_0.5] ( 1 ), [(PhCH₂)₃‐ SnCl]₂ (4,4′‐bpy) ( 2 ), [(n−Bu)₃SnCl]₂(4,4′‐bpy) ( 3 ), [(n−Bu)₂SnCl₂(4,4′‐bpy)] ( 4 ), [Ph₂SnCl₂(4,4′‐bpy)] ( 5 ), and [(PhCH₂)₂SnCl₂(4,4′‐bpy)] ( 6 ). The new complexes have been characterized by elemental analyses, IR, ¹H, ¹³C, ¹¹⁹Sn NMR spectroscopy. The structures of ( 1 ), ( 2 ), ( 4 ), and ( 6 ) have been determined by X‐ray crystallography. Crystal structures of ( 1 ) and ( 2 ) show that the coordination number of tin is five. In complex ( 1 ), two different molecules exist: one is a binuclear molecule bridged by 4,4′‐bpy and another is a mononuclear one, only one N of 4,4′‐bpy coordinate to tin. Complex ( 2 ) contains an infinite 1‐D polymeric binuclear chain by weak Sn…Cl intermolecular interactions with neighboring molecules. In the complexes ( 4 ) and ( 6 ), the tin is six‐coordinate, and the 4,4′‐bpy moieties bridge adjacent dialkyltin(IV)dichloride molecules to form a linear chain. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:338–346, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20016     

Synthesis,Structures, and Some Reactions of [(Thioacyl)thio]‐ and (Acylseleno)antimony and ‐bismuth Derivatives ((RCSS)xMR$\rm{_{{\bf 3 - }{\bf x}}^{\bf 1} }$ and (RCOSe)xMR$\rm{_{{\bf 3 - }{\bf x}}^{\bf 1} }$ with M = Sb,Bi and x = 1–3)

A series of [(thioacyl)thio]‐ and (acylseleno)antimony and [(thioacyl)thio]‐ and (acylseleno)bismuth, i.e., (RCSS)_xMR and (RCOSe)_xMR (M = Sb, Bi, R¹ = aryl, x = 1–3), were synthesized in moderate to good yields by treating piperidinium or sodium carbodithioates and ‐selenoates with antimony and bismuth halides. Crystal structures of (4‐MeC₆H₄CSS)₂Sb(4‐MeC₆H₄) ( 9b′ ), (4‐MeOC₆H₄COSe)₂Sb(4‐MeC₆H₄) ( 12c′ ), (4‐MeOC₆H₄COS)₂Bi(4‐MeC₆H₄) ( 15c′ ), and (4‐MeOC₆H₄CSS)₂BiPh ( 18c ) along with (4‐MeC₆H₄COS)₂SbPh ( 6b ) and (4‐MeC₆H₄COS)₃Sb ( 7b ) were determined (Figs. 1 and 2). These compounds have a distorted square pyramidal structure, where the aryl or carbothioato (= acylthio) ligand at the central Sb‐ or Bi‐atom is perpendicular to the plane that includes the two carbodithioato (= (thioacyl)thio), carboselenato (= acylseleno), or carbothioato ligand and exist as an enantiomorph pair. Despite the large atomic radii, the C?S ??? Sb distances in (RCSS)₂MR¹ (M = As, Sb, Bi; R¹ = aryl) and the C?O ??? Sb distances in (RCOS)_xMR (M = As, Sb, Bi; x = 2, 3) are comparable to or shorter than those of the corresponding arsenic derivatives (Tables 2 and 3). A molecular‐orbital calculation performed on the model compounds (MeC(E)E¹)_3?xMMe_x (M = As, Sb, Bi; E = O, S; E¹ = S, Se; x = 1, 2) at the RHF/LANL2DZ level supported this shortening of C?E ??? Sb distances (Table 4). Natural‐bond‐orbital (NBO) analyses of the model compounds also revealed that two types of orbital interactions n_S → σ and n_S → σ play a role in the (thioacyl)thio derivatives (MeCSS)_3?xMMe_x (x = 1, 2) (Table 5). In the acylthio‐MeCOSMMe₂ (M = As, Sb, Bi), n_O → σ contributes predominantly to the orbital interactions, but in MeCOSeSbMe₂, none of n_O → σ and n_O → σ contributes to the orbital interactions. The n_S → σ and n_S → σ orbital interactions in the (thioacyl)thio derivatives are greater than those of n_O → σ and n_O → σ in the acylthio and acylseleno derivatives (MeCOE)_3?xMMe_x (E = S, Se; M = As, Sb, Bi; x = 1, 2). ?The reactions of RCOSeSbPh₂ (R = 4‐MeC₆H₄) with piperidine led to the formation of piperidinium diphenylselenoxoantimonate(1?) (= piperidinium diphenylstibinoselenoite) (H₂NC₅H₁₀)⁺Ph₂SbSe^?, along with the corresponding N‐acylpiperidine (Table 6). Similar reactions of the bis‐derivatives (RCOSe)₂SbR¹ (R, R¹ = 4‐MeC₆H₄) with piperidine gave the novel di(piperidinium) phenyldiselenoxoantimonate(2?) (= di(piperidinium) phenylstibonodiselenoite), [(H₂NC₅H₁₀)⁺]₂(PhSbSe₂)^2?, in which the negative charges are delocalized on the SbSe₂ moiety (Table 6). Treatment of RCOSeSbR (R, R¹ = 4‐MeC₆H₄) with N‐halosuccinimides indicated the formation of Se‐(halocyclohexyl) arenecarboselenoates (Table 8). Pyrolysis of bis(acylseleno)arylbismuth at 150° gave Se‐aryl carboselenoates in moderate to good yields (Table 9).     

Synthesis and Characterization of Diorganotin(IV) Complexes Bearing Binary Schiff‐Bases and Crystal Structure of nBu2SnL1

Four novel diorganotin(IV) complexes with general formula R₂SnL (R = nBu, PhCH₂) were synthesized from diorganotin dichlorides and binary Schiff‐bases (H₂L) containing N₂O₂ donor atoms in the presence of sodium ethoxide. The Schiff bases were prepared by reactions of o‐phenylenediamine with 3‐tert‐butyl‐2‐hydroxy‐5‐methylbenzaldehyde (H₂L¹) and salicylaldehyde (H₂L²) respectively. The compounds were characterized by elemental analyses, IR, and NMR spectroscopy. The solid‐state crystal structure of the compound nBu₂SnL¹ was determined by single‐crystal structural analysis.     

Synthesis,Spectroscopic, and X‐Ray Diffraction Studies of cis‐Dichlorobis(4‐propanoyl‐2,4‐dihydro‐5‐methyl‐2‐phenyl3 H‐pyrazol‐3‐onato) Tin(IV)

Reaction between an aqueous ethanol solution of tin(II) chloride and that of 4‐propanoyl‐2,4‐dihydro‐5‐methyl‐2‐phenyl‐3 H‐pyrazol‐3‐one in the presence of O₂ gave the compound cis‐dichlorobis(4‐propanoyl‐2,4‐dihydro‐5‐methyl‐2‐phenyl‐3 H‐pyrazol‐3‐onato) tin(IV) [(C₂₆H₂₆N₄O₄)SnCl₂]. The compound has a six‐coordinated Sn^IV centre in a distorted octahedral configuration with two chloro ligands in cis position. The tin atom is also at a pseudo two‐fold axis of inversion for both the ligand anions and the two cis‐chloro ligands. The orange compound crystallizes in the triclinic space group P 1 with unit cell dimensions, a = 8.741(3) Å, b = 12.325(7) Å, c = 13.922(7) Å; α = 71.59(4), β = 79.39(3), γ = 75.18(4); Z = 2 and D_x = 1.575 g cm^–3. The important bond distances in the chelate ring are Sn–O [2.041 to 2.103 Å], Sn–Cl [2.347 to 2.351 Å], C–O [1.261 to 1.289 Å] and C–C [1.401 Å] the bond angles are O–Sn–O 82.6 to 87.7° and Cl–Sn–Cl 97.59°. The UV, IR, ¹H NMR and ¹¹⁹Sn Mössbauer spectral data of the compound are reported and discussed.     

Synthesis,structure and biological activity of diorganotin derivatives with pyridyl functionalized bis(pyrazol‐1‐yl)methanes

Three pyridyl functionalized bis(pyrazol‐1‐yl)methanes, namely 2‐[(4‐pyridyl)methoxyphenyl] bis(pyrazol‐1‐yl)methane (L¹), 2‐[(4‐pyridyl)methoxyphenyl]bis(3,5‐dimethylpyrazol‐1‐yl)methane (L²) and 2‐[(3‐pyridyl)methoxyphenyl]bis(pyrazol‐1‐yl)methane (L³) have been synthesized by the reactions of (2‐hydroxyphenyl)bis(pyrazol‐1‐yl)methanes with chloromethylpyridine. Treatment of these three ligands with R₂SnCl₂ (R = Et, n‐Bu or Ph) yields a series of symmetric 2:1 adducts of (L)₂SnR₂Cl₂ (L = L¹, L² or L³), which have been confirmed by elemental analysis and NMR spectroscopy. The crystal structures of (L²)₂Sn(n‐Bu)₂Cl₂·0.5C₆H₁₄ and (L³)₂SnEt₂Cl₂ determined by X‐ray crystallography show that the functionalized bis(pyrazol‐1‐yl)methane acts as a monodentate ligand through the pyridyl nitrogen atom, and the pyrazolyl nitrogen atoms do not coordinate to the tin atom. The cytotoxic activity of these complexes for Hela cells in vitro was tested. Copyright © 2010 John Wiley & Sons, Ltd.