Tandem mass spectral studies of the fragmentation pathways of organotin compounds of general formula R3SnR′

Positive ion‐electron impact (EI) mass spectra of organotin compounds of the type R₃SnR′, where R = Ph, n−Bu, n−Pe and R′ = allyl, vinyl, H and Ph, have been recorded. The spectra were also examined by tandem mass spectrometry (MS‐MS) in order to establish fragmentation reaction mechanisms for compounds bearing mixed substituents. Fragmentation patterns of six organotin compounds, based on precursor‐product ion relationships are proposed. Significant differences were found in the reaction pathways of organotin compounds with different substituents. This technique has potential to predict the effect of substitution on the mass spectra of organotin compounds. Copyright © 2000 John Wiley & Sons, Ltd.     

Intramolecularly Coordinated Organotin Tellurides: Stable or Unstable?

The step-wise oxidation of an organotin(I) compound with elemental tellurium gave a variety of unprecedented organotin tellurides containing tin atoms in the oxidation states +II and +IV.     

Preparation and structural studies on organotin(IV) complexes with flavonoids

Fourteen complexes of di-n-butyltin(IV)²⁺ cations with flavonoid glycosides (rutin, hesperidin, 2′,4′,3-trihydroxy-5′,4-dimetoxychalkone 4-rutinoside) and flavonoid aglycones (quercetin, morin, hesperitin and sorte flavones) were prepared. The composition of the complexes was determined by standard analytical methods. The results showed that complexes containing diorganotin(IV)²⁺ moiety and the ligand in 1∶1, 2∶1 or 3∶1 ratio are formed. The FTIR spectra were consistent with the presence of Sn-O (phenol or carbohydrate) vibration in the compounds. The structure of the complexes was measured by Mössbauer spectroscopy. Comparison of the experimental quadrupole splitting with those calculated on the basis of partial quadrupole splitting concept revealed that the complexes are of four types: with the central tin atoms surrounded by donor atoms in a purely trigonal-bipyramidal, octahedral+trigonal-bipyramidal, trigonal-bipyramidal+tetrahedral and octahedral+tetrahedral arrangement. This procedure also distinguished between the different structural isomers of both trigonal-bipyramidal and octahedral complexes. Conclusions could therefore be drawn on the factors determining which of the isomers are formed in the systems. The Mössbauer parameters obtained for organotin(IV)-flavonoid complexes were compared with those measured for organotin(IV)-carbohydrate complexes.     

Structural analysis of 2,6-[bis(alkyloxy)methyl]-phenyltin derivatives using electrospray ionization mass spectrometry

Electrospray ionization (ESI) mass spectrometry was applied to the structural analysis of 23 2,6-[bis(alkyloxy)methyl]phenyltin(IV) derivatives. The mass spectra were measured in both polarity modes and multistage tandem mass spectrometric (MS(n)) measurements were performed on the ion trap analyser for positively charged tin-containing ions. The sum of complementary ions observed in the positive-ion mode (i.e. [M-R(3)](+) ion) and in the negative-ion mode (i.e. [R(3)](-) ion) permits molecular mass determination in spite of the fact that the molecular adducts were often missing even in the first-order mass spectra. The subsequent fragmentation of [M-R(3)](+) ions studied by MS(n) and the correlation of observed fragment ions with the expected structures of synthesized organotin(IV) compounds allowed us to understand the fragmentation behaviour and the mechanism of the ion formation for studied compounds. The typical neutral losses are alkenes, alcohols and aldehydes. The fragmentation pattern of one selected compound was supported by MS(n) measurements of an isotopically labelled analogue to confirm unusual ion-molecule reactions of some fragment ions with water in the ion trap.     

Tin(IV) cyanoximates: synthesis, characterization, and cytotoxicity

In recent years, numerous organotin(IV) derivatives have exhibited remarkable cytotoxicity against several types of cancer. However, the properties of the cyanoxime-containing organotin(IV) complexes are unknown. Previously, it has been shown that cyanoximes displayed an interesting spectrum of biological activity ranging from growth-regulation to antimicrobial and pesticide detoxification actions. The work presented here attempts to combine the useful properties of both groups of compounds and investigate the likely antiproliferating activity of the new substances. A series of 19 organotin(IV) complexes, with nine different cyanoxime ligands, were anaerobically prepared by means of the heterogeneous metathesis reaction between the respective organotin(IV) halides (Cl, Br) and ML (M=Ag, Tl; L=cyanoximate anion), using an ultrasound in the CH3CN at room temperature. The compounds were characterized using spectroscopic methods (UV-visible, IR, 1H,13C NMR, 119Sn M?ssbauer) and X-ray analysis. The crystal structures of the complexes revealed the formation of two types of tin(IV) cyanoximates: mononuclear five-coordinated compounds of R4-xSnLx composition (R=Me, Et, n-Bu, Ph; x=1, 2; L=cyanoximate anion), and the tetranuclear R8Sn4(OH)2O2L2 species (R=n-Bu, Ph). The latter complex contains a planar [Sn4(OH)2O2]2- core, consisting of three adjacent rhombs with bridging oxo and hydroxo groups. The tin(IV) atoms are five-coordinated and have distorted trigonal-pyramidal surrounding. This is the first instance when the organic anions were found to act as monodentate O-bound planar oxime ligands. All of the compounds were studied in vitro for antiproliferating activity, using human cervical cancer HeLa and WiDR colon cancer cell lines; cisplatin was used as a positive control substance. The two dibutyltin(IV) cyanoximates showed cytotoxicity similar and greater to that of cisplatin.     

Substoichiometric determination of inorganic tin in organotin compounds

Inorganic tin(IV) present in organotin compounds is determined substoichiometrically by complexation with salicylideneamino-2-thiophenol in a non-aqueous medium, after isolation of the tin(IV) by iodide extraction. The method is applied to the degradation products in commercial chemicals and those formed by u.v.-irradiation.     

Synthesis and <Emphasis Type="Italic">in vitro</Emphasis> Fungicidal Study of Organotin(IV) Complexes of Monomethyl Glutarate

The synthesis and study of new coordination compounds of some organotin(IV) chlorides with monomethyl glutarate are reported. The ligand molecule appears to be bound to the tin atom through the carboxylic oxygen. The results obtained from ¹H, ¹³C, and ¹¹⁹Sn NMR, FT-IR and ¹¹⁹Sn Mossbauer spectra show that the complexes are pentacoordinated with the trigonal bipyramidal structure. Biological screening of organotin(IV) derivatives shows promising activity, especially for the triphenyltin complex exhibiting higher antifungal activity. In addition, the rest of the compounds also prove to be active against various fungi used.     

含氮杂环三烃基锡衍生物的合成及其生物活性

本文合成了14个含氮杂环三烃基锡衍生物,红外光谱,核磁共振谱和质谱的研究表明三烃基锡-1,2,4-三氮唑为以氮原子作桥联的五配位聚合结构化合物,化合物的生物活性和生物选择性主要取决于锡原子上的三烃基。     

Structural investigations on diorgano- and triorganotin(IV) derivatives of [meso-tetra(4-sulfonatophenyl)porphine] metal chlorides

Several new complexes of organotin(IV) moieties with MCl_n[meso-tetra(4-sulfonatophenyl)porphine], (R₂Sn)₂MCl_n[meso-tetra(4-sulfonatophenyl)-porphinate]s and (R₃Sn)₄MCl_n [meso-tetra(4-sulfonatophenyl)porphinate]s, [M = Fe(III), Mn(III): n = 1, R = Me, n-Bu; Ph; M = Sn(IV): n = 2, R = Me, n-Bu] have been synthesized and their solid state configuration investigated by infrared (IR) and Mössbauer spectroscopy, and by ¹H and ¹³C NMR in D₂O.The electron density on the metal ion coordinated inside the porphyrin ring is not influenced by the organotin(IV) moieties bonded to the oxygen atoms of the side chain sulfonatophenyl groups, as it has been inferred on the basis of Mössbauer spectroscopy and, in particular, from the invariance of the isomer shift of the Fe(III) and Sn(IV) atoms coordinated into the porphyrin square plane of the newly synthesized complexes, with respect to the same atoms in the free ligand.As far as the coordination polyhedra around the peripheral tin atoms are concerned, infrared spectra and experimental Mössbauer data would suggest octahedral and trigonal bipyramidal environments around tin, in polymeric configurations obtained, respectively, in the diorganotin derivatives through chelating or bridging sulfonate groups coordinating in the square plane, and in triorganotin(IV) complexes through bridging sulfonate oxygen atoms in axial positions.The structures of the (Me₃Sn)₄Sn(IV)Cl₂[meso-tetra(4-sulfonatophenyl)porphinate] and of the two model systems, Me₃Sn(PS)(HPS) and Me₂Sn(PS)₂ [HPS = phenylsulfonic acid], have been studied by a two layer ONIOM method, using the hybrid DFT B3LYP functional for the higher layer, including the significant tin environment. This approach allowed us to support the structural hypotheses inferred by the IR and Mössbauer spectroscopy analysis and to obtain detailed geometrical information of the tin environment in the compounds investigated.¹H and ¹³C NMR data suggested retention of the geometry around the tin(IV) atom in D₂O solution.     

Microanalytical determination of tin in organotin compounds

Existing procedures for the determination of tin in organotin compounds are reviewed, and a new procedure is described which can be used for the rapid microanalysis of most organotin compounds. Wet oxidation with sulphuric acid and 30% hydrogen peroxide is followed by spectrophotometric determination of the extracted ternary tin(IV)-chloride-oxine complex in chloroform. Time for a single determination is 20 min, and the relative standard deviation is 0.7% for 1-5 mg of tin. On account of their volatility, methyltin compounds must be subjected to a sealed-tube wet oxidation in sulphuric-nitric acid mixture. Addition of sulphamic acid after boiling to remove most of the nitric acid makes this compatible with the solvent extraction step. Tin present as organotin stabilizer in PVC samples can also be determined by this method, after destruction of the organic matter with sulphuric acid and 50% hydrogen peroxide.     

Di- and tri-organotin(IV) diphenyldithiophosphinates

Di- and tri-organotin(IV) diphenyldithiophosphinates, R₂Sn(S₂PPh₂)₂ (R = Me, n-Bu, Bz, Ph) and R₃SnS₂PPh₂ (R = Me, Cy, Bz, Ph) were prepared by reaction of the corresponding organotin chlorides or oxides with diphenyldithiophosphinic acid or its ammonium salt. All the compounds were characterized by IR and ¹H NMR spectra. For R₂Sn(S₂PPh₂)₂ (R = Me, Ph) and Ph₃SnS₂PPh₂ mass spectra and tin-119m Mössbauer spectra were also recorded. Monodentate bonding of the dithiophosphinic ligand and tetrahedral structures are proposed for the triorganotin derivatives, while in diorganotin compounds there appears to be distorted octahedral geometry around tin, with anisobidentate dithiophosphonic ligands.     

Di- and Tri-organotin(IV) Complexes of N-Acetyltriglycine and N-Benzoyltriglycine: Synthesis and Spectroscopic Characterization

Di- and tri-organotin(IV) derivatives of N -acetyltriglycine and N -benzoyltriglycine (HA) were obtained by refluxing equimolar mixtures of the ligand and the organotin(IV) oxide or hydroxide in methanol or acetone. According to the spectroscopic data, triorganotin(IV) derivatives adopt a trigonal-bipyramidal structure in which the planar R₃Sn^IV unit is bonded by a monodentate carboxylate group and a donor group, presumably the amide CO. The reaction of HA with the appropriate diorganotin(IV) compounds gave both dicarboxylates R₂SnA₂, with six-coordinated tin, and dimeric tetraorganodistannoxanes {[R₂SnA]₂O}₂, in which the tin atoms are essentially five-coordinated.     

Self-assembly of diorganotin(IV) moieties and 2-pyrazinecarboxylic acid: syntheses, characterizations and crystal structures of monomeric, polymeric or trinuclear macrocyclic compounds

A series of diorganotin(IV) compounds of the type [R(2)Sn(pca)Cl](3)(R = CH(3); (n)Bu; C(6)H(5); C(6)H(5)CH(2); Hpca = 2-pyrazinecarboxylic acid), R(2)Sn(pca)(2)(mH(2)O)xnH(2)O (m= 1: R = CH(3), n= 2, R =(n)Bu, n= 0; m= 0, n= 0: R =(n)Bu, C(6)H(5), C(6)H(5)CH(2)) and (Et(3)NH)(+)[R(2)Sn(pca)(2)Cl](-)xmH(2)O (m= 0: R = CH(3), (n)Bu, C(6)H(5)CH(2); m= 1: R = C(6)H(5)) have been obtained by reactions of 2-pyrazinecarboxylic acid with diorganotin(iv) dichloride in the presence of sodium ethoxide or triethylamine. All compounds were characterized by elemental, IR and NMR spectra analyses. Except for compounds, and, the others were also characterized by X-ray crystallography diffraction analyses, which revealed that compounds and were trinuclear macrocyclic structures with six-coordinate tin(IV) atoms, compounds and were monomeric structures with seven-coordinate tin(IV) atoms, compounds and were polymeric chain structures with seven-coordinate tin(IV) atoms and compounds and were stannate with seven-coordinate tin(IV) atoms.     

三(2-甲基-2-苯基丙基)锡芳氧乙酸酯的合成

三（２－甲基－２－苯基丙基）锡芳氧乙酸酯的合成刘宝殿,宁志刚,朱东升,包明（东北师范大学化学系,长春,１３００２４）关键词三（２－甲基－２－苯基丙基）锡芳氧乙酸酯,三（２－甲基－２－苯基丙基）氢氧化锡,芳氧乙酸,杀螨活性１９６６年Ｒｅｉｃｈｌｅ［１］...     

Synthesis and Characterization of Biologically Potent Di‐organotin(IV) Complexes of Mono‐Methyl Glutarate

The synthesis and characterization of some novel compounds of organotin(IV) chlorides with monomethyl glutarate is reported; the ligand molecule appears to be bound to the tin atom through the carbonyl oxygen. The results obtained through ¹H‐¹³C‐¹¹⁹Sn NMR, FT‐IR and ¹¹⁹Sn Mössbauer spectra show that the diorganotin(IV) complexes have hexacoordination with octahedral geometry. Biological screening of the complexes reveals that the diorganotin(IV) complexes show significant activity against all microorganisms.     

Synthesis and spectroscopic studies of organotin compounds containing the SnS bond

The preparation of a number of organotin(IV) compounds, containing SnS bonds, is described. Their ¹³C and ¹H NMR and IR spectra are presented. In cases where either SnS or SnN may be expected, Mössbauer spectra show two sets of peaks consistent with these possibilities.     

Neue mehrkernige Organozinn(IV)–Stickstoff‐Verbindungen. Synthese und Kristallstrukturen von [(PhSn)4(NPh)5Cl2] und [(MeSn)4(NHPh)4(NPh)4]

New Polynuclear Organotin(IV)–Nitrogen Compounds. Synthesis and Crystal Structures of [(PhSn)₄(NPh)₅Cl₂] and [(MeSn)₄(NHPh)₄(NPh)₄] The reaction of the organotin halides PhSnCl₃ and MeSnCl₃ with LiNHPh leads to the formation of two new nitrogen bridged organotin compounds, [(PhSn)₄(NPh)₅Cl₂] ( 1 ) and [(MeSn)₄(NHPh)₄(NPh)₄] ( 2 ). The crystal structures of 1 and 2 have been determined by low temperature X‐ray diffraction. 1 contains a bicyclic Sn₄N₅ framework, which consists of two six‐membered Sn₃N₃‐rings. All tin atoms are coordinated nearly tetrahedrally. Two tin atoms are bonded to a phenyl group and three nitrogen atoms, the other two tin atoms are coordinated by a phenyl group, two nitrogen atoms and a terminal chlorine atom. In 2 the tin atoms define the corners of a distorted square. Each edge of the square is bridged by a μ²‐NHPh and a μ²‐NPh group. The bridging NHPh and NPh groups are arranged at opposite sides of the Sn₄ plane. The tin atoms are coordinated square pyramidally by 4 nitrogen atoms and a methyl group.     

Triphenyltin(IV) compounds with biologically active anionic groups: Crystal and molecular structures of the p-ethoxybenzoic acid,acetylsalicylic acid,phthalic acid and salicylaldehyde derivatives

Triphenyltin(IV) compounds of p-ethoxybenzoic acid and acetylsalicylic acid contain molecular units with Sn–O bonds and distorted tetrahedral tin centers. The phthalic acid derivative contains two four-coordinate tin atoms between which the phthalic acid unit effectively forms a bridge. The salicylaldehydato compound is polymeric with trigonal bipyramidal tin centers in which the phenyl groups take equatorial positions. The polymerization occurs via the aldehyde oxygen atom bonding to a neighboring tin atom. © 1998 John Wiley & Sons, Ltd.     

Structural chemistry of organotin(IV) complexes

The amazing structural diversity in organotin compounds is discussed in the systems containing -O and -S donor ligands. It is demonstrated that there exist a fascinating range of structural diversity for organotin(IV) complexes, including differences in coordination number and molecular geometry. The difference in structure is correlated with the nature of tin and ligand bonded R groups. Despite the large number of different structures found in organotin(IV) carboxylates, there is limited range of coordination geometries about the Sn atom. The four coordinated Sn atom in triorganotin(IV) complexes is invariably distorted tetrahedral and five coordinated Sn is distorted trigonal bipyramidal. A large range has been observed for diorganotin carboxylate structures, where five, six and seven coordinate geometries have been reported. The Sn atom in mono-organotin has only been demonstrated to exist in distorted octahedral geometries (the single exception being a pentagonal bipyramidal geometry). In the case of organotin(IV) complexes of S donor ligands, it has been shown that there exists a rich diversity in Sn atom geometries and coordination modes of the sulfur donor ligands themselves. As in related carboxylate systems, the assignment of coordination numbers to the Sn centers in some compounds is controversial. As a general trend, it has been shown that, the overall coordination number at the Sn atom decreases with the increasing number of organic substituents at the Sn atom. This phenomenon is usually achieved by increased asymmetry in the mode of coordination of the sulfur donor ligands.     

The chemistry of hexahydro-1,2,4,5-tetrazines—II: Mass spectra of 1,4-dialkylhexahydro-1,2,4,5-tetrazines and 1,4-dialkyl-2,5-diacylhexahydro-1,2,4,5-tetrazines

The mass spectra of twenty-eight 1,4-dialkylhexahydro-1,2,4,5-tetrazines and 1,4-dialkyl-2,5-diacylhexahydro-1,2,4,5-tetrazines (1) have been recorded and interpreted with the aid of deu-terium labelling, high resolution measurements, and the metastable defocusing technique. The principal fragmentations involve initial scission of ring bonds, particularly C-N bonds, leading to characteristic ions of mass M/2 and M/2± 1, and to 2,3-diaza-1,3-butadienyl ions (II). In the spectra of acylated compounds, acyl migration occurs within the molecular ion. The elimination of formaldehyde from the principal fragment ion is discussed.