Tin Anions Research Articles

Ate-complexes of tris-dioxolene tin anion with nickel (or cobalt) bis-(2,2ʹ-dipyridine)-dioxolene cation. EPR study of spin migration dynamics. Solvent and counterion effects

Reaction of bis-o-semiquinonato nickel complex (2,2ʹ-dipyridine)Ni(dioxolene)2 (1) (dioxolene here – mono- or double-reduced forms of 3,6-di-tert-butyl-o-benzoquinone) or its cobalt analogue (2,2ʹ-dipyridine)Co(dioxolene)2) with (2,2ʹ-dipyridine)Sn(dioxolene)2 occur through ligands exchange and results in ate-complex [(2,2ʹ-dipyridine)2M(dioxolene)]+ [Sn(dioxolene)3]- (M = Ni (2), Co(3)). According to single crystal x-ray diffraction study both products are isostructural. Geometry of tin anion is intermediate between octahedral and trigonal prism. Analysis of bonds lengths in chelate cycles in tin anion one of dioxolene ligands is semiquinone anion-radical whereas the other two are catecholato-dianions. Geometry of inner coordination core of both cations is close to octahedral. Cobalt being in 3+ oxidation state is connected to catecholato-dianion. Nickel being in 2+ oxidation state is connected to semiquinonato anion-radical. Variable temperature magnetic susceptibility measurements of 2 indicate high spin nickel ferromagnetically coupled with semiquinonato anion-radical connected to it and independent semiquinone coordinated to tin. Cobalt cation is diamagnetic. EPR studies of ate-complex 3 in solution indicate two independent dynamic processes: solvation and migration of unpaired electron between three structurally identical ligands. Rate of this migration depends on solvent and temperature: from slow (CCl4, toluene) to fast (MeOH, CH3CN) in EPR time scale. Solvent role is solvation of the tin anion on one hand and the extent of isolation of ions: from “close pair” in CCl4 to “solvate separated pair” in methanol on the other hand. It is determined by solvent permittivity and dipole moment. Temperature dependence of hyperfine coupling constant with tin magnetic nuclei allowed estimating enthalpy and entropy of solvation. Temperature dependence of EPR spectrum shape together with it simulation allowed to evaluate the rates of spin migration and it activation parameters. In general, the regularities of ate-complex 2 behavior are the same but EPR lines are broader because of presence of high spin nickel and cation polarity effect is less than that in 3 because of smaller charge separation.

Bismuth-Doped Tin Clusters: Experimental and Theoretical Studies of Neutral Zintl Analogues

The electron count of gas-phase clusters is increased gradually by element substitution in order to mimic the total number of electrons of known stable closo-clusters. A combination of elements from the fourth and fifth group of the periodic table such as Sn and Bi is well-suited for this approach. Hence, these small Sn-Bi clusters are investigated by employing the electric field deflection method. For clusters in the series Sn(M-N)Bi(N) (M = 5-13, N = 1-2), the beam profiles obtained in cryogenic experiments are dominated by beam broadening, indicating the presence of a permanent electric dipole moment that is sensitive to the (rigid) cluster structure. An intensive search for the global minimum structure employing a density functional theory/genetic algorithm method is performed. Dielectric properties for the identified low-energy isomers are computed. The structural and dielectric properties are used in beam profile simulations in order to discuss the experimental data. Comparison of theoretical and experimental results enables identification of the growing pattern of these small bimetallic clusters. For multiply doped clusters, it is concluded that the dopant atoms do not form direct Bi-Bi bonds, but more interestingly, a rearrangement of the cluster skeleton becomes apparent. The structural motifs are different from pure tin clusters but rather are rationalized using the corresponding structures of tin anions or are based on the Wade-Mingos concept. Further evidence for this idea is deduced from nuclear independent chemical shift calculations, which show nearly identical behavior for negatively charged pure and neutral bimetallic clusters. All of these findings are consistent with the idea of neutral Zintl analogues in the gas phase.

ChemInform Abstract: Solid State Compounds with Tin-Tin Bonding. Yb36Sn23: A Novel Compound Containing Oligomeric Tin Anions.

ChemInform Abstract: Solid State Compounds with Tin-Tin Bonding. Yb36Sn23: A Novel Compound Containing Oligomeric Tin Anions.

Solid State Compounds with Tin−Tin Bonding. Yb36Sn23: A Novel Compound Containing Oligomeric Tin Anions

Reaction of appropriate amounts of the elements in Ta at 1100 °C leads to formation of the title phase in high yield. Hydrogen impurities in small amounts do not obscure its formation. Yb36Sn23 crystallizes in tetragonal space group P4/mbm (No. 127) with a = 12.3869(5) A, c = 22.935(1) A, Z = 2. The structure features a linear tin hexamer, five dimers, and seven isolated tin atoms per formula unit. These proportions lead to a closed-shell oxidation state count for simple octet assignments (Yb+2)36(Sn6-14)(Sn2-6)5(Sn-4)7 and a Zintl phase classification. Dimensionally, all cations appear to be YbII. The hexamer of tin atoms has as its genesis the close contact of Sn atoms that center confacial square antiprismatic arrangements of Yb atoms (closely related to the parent W5Si3 structure). These interconnect with elongated square prisms in a 6:1 proportion to generate the n = six member of Parthe's homologous series A5n+6B3n+5. Electrical conductivity measurements as a function of temperature show that the co...

Preparation and some reactions of neophyltin anions

A study on the preparation of trineophyltin and mixed methylneophyltin anions and subsequent reactions of these anions is reported. It was found that whereas mixed hydrides Me n Nph 3− n SnH ( n = 1,2) react with NaH in DMSO to give the corresponding organotin sodium anions (60–70% yield), trineophyltin hydride reacts with NaH to give hexaneophylditin as the only product (32%). The reaction of tin halides Me n Nph 3− n X (X = Cl, Br; n = 0, 1, 2) with lithium in THF yields the corresponding organotinlithium anions (70%). The tin anions were reacted with various alkyl halides. The 1,4 addition of trineophyltinlithium ( 10 ∗) to α,β-unsaturated enones followed by the reaction of the intermediate carbanions with methyl iodide, leads with benzylideneacetone to a mixture of the corresponding threo (34%) and erythro (25%) diastereoisomers. Under the same reaction conditions, the addition of 10 ∗ to chalcone proceeded with complete stereoselectivity to give the diastereoisomer threo (60%) as the only product. Full 1H and 13C NMR data of the new organotins are given.

Structural studies of diorganotin(IV) carboxylates. X-ray and NMR structures of Me2Sn(OAc)2 and a 7-coordinate tin anion, Me2Sn(OAc)3NMe4.cntdot.2CHCl3

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStructural studies of diorganotin(IV) carboxylates. X-ray and NMR structures of Me2Sn(OAc)2 and a 7-coordinate tin anion, Me2Sn(OAc)3NMe4.cntdot.2CHCl3Thomas P. Lockhart, Joseph C. Calabrese, and Fredric DavidsonCite this: Organometallics 1987, 6, 12, 2479–2483Publication Date (Print):December 1, 1987Publication History Published online1 May 2002Published inissue 1 December 1987https://doi.org/10.1021/om00155a003RIGHTS & PERMISSIONSArticle Views230Altmetric-Citations92LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (665 KB) Get e-AlertsSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts

The photolysis of rigid solutions of triphenyl tin anion

The alkali metal reduction in vacuo of Ph 4Sn, Ph 6Sn 2, or Ph 3SnCl in tetrahydrofuran (THF) or 2-methyltetrahydrofuran (MTHF) solution proceeds stoichiometrically to yield Ph 3Sn −. The near UV photolysis at 93 K of rigid THF or MTHF glasses of Ph 3Sn − generates the Ph 3Sn radical. A g value of 1.998 ± 0.001, obtained from analysis of the electron spin resonance (ESR) spectrum, is compared with results reported in single crystal matrices and in gas phase condensations.

Crystal and molecular structure of tris(hexaamminerhodium(III)) tetrakis(trichlorostannato(II))(tetrachlorostannato(II)rhodate(I) hexachlorostannate(II) tetrahydrate

The crystal and molecular structure of the title compound, [Rh(NH 3) 6] 3[Rh(SnCl 3) 4(SnCl 4)] [SnCl 6] · 4H 2O, has been determined by the single-crystal X-ray diffraction method. The compound crystallizes in the monoclinic system, space group P2 n with a = 16.581(2), b = 11.010(4), c = 16.024(2)Å, β = 90.76(1), and two molecules per unit cell. The structure was solved by Patterson's method and refined by the least-squares technique to give a final R factor of 0.031. The three cations, [Rh(NH 3) 6] 3+, are a regular octahedron with an average RhN bond length of 2.07 Å. The rhodium anion, [Rh(SnCl 3) 4(SnCl 4)] 5−, is a trigonal bipyramid with the two axial RhSn bonds, 2.493 Å in length, and the three equatorial bonds, 2.546, 2.540, and 2.540 Å. One of the three tin atoms in the equatorial trigonal plane forms a distorted trigonal bipyramid with two short SnCl bonds 2.384 Å in length and two long bonds, 2.733 Å. The other four tin atoms have a distorted tetrahedral arrangement with an average SnCl bond length of 2.42 Å. The tin anion, [SnCl 6] 4−, which is not coordinated to rhodium, forms extremely long SnCl bonds of 2.763, 2.800, and 2.893 Å in a distorted octahedral arrangement.