Coordinated Tin Atoms Research Articles

Red and Blue-Black Tin Monoxide, SnO: Pitfalls, Challenges, and Helpful Tools in Crystal Structure Determination of Low-Intensity Datasets from Microcrystals

The crystal structures of red and blue-black tin(II) oxide, SnO, have been determined for the first time by single-crystal X-ray diffraction. Blue-black SnO crystallizes in the tetragonal space group P4/nmm, representing a layer structure consisting of the square–pyramidally coordinated tin and slightly distorted tetrahedrally coordinated oxygen atoms, in accordance with previous results. In contrast, red SnO crystallizes in the orthorhombic centrosymmetric space group Pbca rather than in the non-centrosymmetric space group Cmc21, as assumed for a long time. Its layer structure consists of very regular, trigonal–pyramidally coordinated tin atoms as well as trigonal–planar coordinated oxygen atoms. Special care was taken on space group determination, including lattice centering. C-centering could be excluded because of systematic absence violations detected when collecting and processing a primitive triclinic dataset and by generating precession images. In the absence of meaningful extinction conditions resulting from the very small crystal under examination, the structure was initially solved and refined in the triclinic space group P1. Subsequently, the observed atom coordinates were used to reconstruct the actual symmetry skeleton. The various possibilities to identify the correct space group starting from the triclinic solution are demonstrated, and the unique structural features of the crystal structure are visualized.

Variation of Aluminium Distribution in Small-Sized ZSM-5 Crystals during Desilication.

Hollow ZSM-5 zeolites of size below one micrometer can be produced by desilication of crystals with aluminium zoning. The parent crystals have a core-shell structure: the core part has nearly no aluminium, whereas the aluminium content in the shell increases when extending to exterior surface. Transmission electron microscopy confirmed the preservation of the crystalline shell after base leaching, but could not identify its subtle change. An increase of the Si/Al ratio of the surface was detected upon leaching the parent material to form the hollow zeolite by using ambient pressure X-ray photoelectron spectroscopy and infrared spectroscopy of substituted alkylpyridines. 27 Al MAS NMR showed that base leaching results in a reduced percentage of distorted tetrahedrally coordinated aluminium. The reprecipitation of dissolved species occurs and tetrahedrally coordinated tin atoms can thus be introduced to the shell framework. Overall, the formation of hollow ZSM-5 zeolites by desilication involves not only the removal of silicon-rich core, but also a reduced percentage of exterior aluminium-related acid sites, which should be considered while using hollow zeolites in acid-catalyzed reactions.

On the structural diversity anions coordinate to the butterfly-shaped [(R2Sn)3O(OH)2]2+ cations and vice versa

The syntheses and crystal structures of [(t-Bu2Sn)3O(OH)2]CO3·3MeOH, 1a, [(t-Bu2Sn)3O(OH)2]CO3·3H2O·acetone, 1b, [(t-Bu2Sn)3O(OH)2][I]2·[(t-Bu2Sn(OH)I]2·2DMSO, 1c, and [(Cy2Sn)3O(OH)2][I]2·2DMSO, 2a, all containing the trinuclear [(R2Sn)3O(OH)2]2+ ion have been described. The butterfly shape of this cation is derived from two annulated, four-membered tin–oxygen rings with a central μ3-oxygen atom and trigonal-bipyramidally coordinated tin atom both belonging to both rings and two μ2-hydroxyl groups and two outer, four-fold coordinated tin atoms. In 1a and 1b, the carbonate anions interact with the outer tin atoms of the cations as bidentate chelating ligands in the classical syn–syn coordination mode, and vice versa. In this way, both outer tin atoms expand their coordination sphere from four to five, with the consequence that bond angles and lengths within the cation are determined by the axial and equatorial position of the oxygen atoms within the trigonal-bipyramidal coordination on all three tin atoms. 1c consists of two different building units, an up to now unknown hydroxide iodide of composition [(t-Bu2Sn(OH)I]2 with hydrogen-bonded DMSO molecules and a [(t-Bu2Sn)3O(OH)2]2+ cation with one coordinated and one isolated, via hydrogen bonds connected iodine ion. The hydroxide iodine is built up of two five-fold coordinated tin atoms linked via two hydroxyl groups with exocyclic iodine atoms occupying axial positions at the trigonal-biypramidally coordinated tin atoms. The unprecedented coordination of the iodine ion to the [(t-Bu2Sn)3O(OH)2]2+ cation takes place between both outer tin atoms, resulting in a five-fold, trigonal-bipyramidal coordination at these tin atoms, too. Structural parameters within the so-formed [(t-Bu2Sn)3O(OH)2I]+ complex are very similar to those of 1a and 1b, with the exception of a significant lengthening of the tin–oxygen bonds opposite to the bridging iodine atom. 2a represents the first example of the [(R2Sn)3O(OH)2]2+ cation without R = t-butyl, so far. In the solid, it consists of two crystallographic independent [(Cy2Sn)3O(OH)2][I]2 building units, each connected to two DMSO molecules via hydrogen bonds. Both building units are very similar with respect to their conformation. Each of the iodine anions coordinates with only one of the two outer tin atoms, one in an inwards, one in an outwards to the tin-oxygen framework directed position. These tin atoms are therefore also trigonal-bipyramidally coordinated as in 1a−1c, but because of steric reasons one of the trigonal-bipyramids has changed its orientation within the tin–oxygen framework, accompanied by enormous changes of bond lengths and angles therein.

Manganese–Tin Triple Bonds: A New Synthetic Route to the Manganese Stannylidyne Complex Cation trans-[H(dmpe)2Mn≡Sn(C6H3-2,6-Mes2)]+ (dmpe = Me2PCH2CH2PMe2, Mes = 2,4,6-Trimethylphenyl)

A new approach to the first complex featuring a manganese-tin triple bond that takes advantage of the propensity of dihydrogen complexes to eliminate H2 is reported. Reaction of the 18-valence-electron manganese dihydrogen hydride complex [MnH(η(2)-H2)(dmpe)2] (1) (dmpe = Me2PCH2CH2PMe2) with the organotin(II) chloride SnCl(C6H3-2,6-Mes2) (Mes = 2,4,6-trimethylphenyl) selectively afforded by H2 elimination the chlorostannylidene complex trans-[H(dmpe)2Mn═Sn(Cl)(C6H3-2,6-Mes2)] (2), which upon treatment with Na[B(C6H3-3,5-(CF3)2)4] and Li[Al(OC(CF3)3)4] was transformed quantitatively into the stannylidyne complex salts trans-[H(dmpe)2Mn≡Sn(C6H3-2,6-Mes2)]A [A = B(C6H3-3,5-(CF3)2)4 (3a), Al(OC(CF3)3)4 (3b)]. Complexes 2 and 3a/3b were fully characterized, and the structures of 2 and 3a were determined by single-crystal X-ray diffraction. Complex 2 features the shortest Mn-Sn double bond reported to date, a large Mn-Sn-Caryl bond angle, and a long Sn-Cl bond of the trigonal-planar-coordinated tin center. These bonding features can be rationalized in valence-bond terms by a strong contribution of the triply bonded resonance structure [LnMn≡SnR]Cl and were verified by a natural resonance theory (NRT) analysis of the electron density of the DFT-minimized structure of 2. Complex 3a features the shortest Mn-Sn bond reported to date and a linearly coordinated tin atom. Natural bond order and NRT analyses of the electronic structure of the complex cation in 3a/3b suggested a highly polar Mn-Sn triple bond with a 65% ionic contribution to the NRT Mn-Sn bond order of 2.25. Complex 3a undergoes reversible one-electron reduction, suggesting that open-shell stannylidyne complexes might be accessible using strong reducing agents.

Catena-Poly[[dimethylbis(thiocyanato-κN)tin(IV)]-μ-(4,4′-bipyridine-κ2N:N′)

The title dimethyl­tin diisothio­cyanate adduct of 4,4′-bipyridine, [Sn(CH3)2(NCS)2(C10H8N2)]n, adopts a chain motif in which the N-heterocycle functions as a bridge to adjacent all-trans octa­hedrally coordinated tin atoms. The SnIV atom lies on a special position of 2/m site symmetry, the methyl C atom on a special position of 2 site symmetry, and the thio­cyanate and 4,4′-bipyridine on a special position of m site symmetry.

Synthesis, structural characterization and electrochemistry of C,N-chelated organotin(IV) dicarboxylates with ferrocenyl substituents

A set of C,N-chelated organotin(IV) ferrocenecarboxylates, [L CN( n-Bu)Sn(O 2CFc) 2] ( 1), [(L CN) 2Sn(O 2CFc) 2] ( 2), [L CN( n-Bu)Sn(O 2CCH 2Fc) 2] ( 3), [L CN( n-Bu)Sn(O 2CCH 2CH 2Fc) 2] ( 4), [L CN( n-Bu)Sn(O 2CCH CHFc) 2] ( 5), [L CN( n-Bu)Sn(O 2CfcPPh 2) 2] ( 6), [(L CN) 2Sn(O 2CfcPPh 2) 2] ( 7), and [L CN( n-Bu) 2Sn(O 2CFc)] ( 8) (L CN = 2-( N,N-dimethylaminomethyl)phenyl, Fc = ferrocenyl and fc = ferrocene-1,1′-diyl) has been synthesized by metathesis of the respective organotin(IV) halides and carboxylate potassium salts and characterized by multinuclear NMR and IR spectroscopy. The spectral data indicated that the tin atoms in diorganotin(IV) dicarboxylates bearing one C,N-chelating ligand ( 1 and 3- 6) are seven-coordinated with a distorted pentagonal bipyramidal environment around the tin constituted by the n-butyl group, the chelating L CN ligand and bidentate carboxylate. Compounds 2 and 7 possessing two chelating L CN ligands comprise octahedrally coordinated tin atoms and monodentate carboxylate donors, whereas compound 8 assumes a distorted trigonal bipyramidal geometry around tin with the carboxylate binding in unidentate fashion. The solid state structures determined for 1⋅C 6D 6 and 2 by single-crystal X-ray diffraction analysis are in agreement with spectroscopic data. Compounds 1, 3–5, and 8 were further studied by electrochemical methods. Whereas the oxidations of ferrocene units in bis(carboxylate) 2 and monocarboxylate 8 proceed in single steps, compound 1 undergoes two closely spaced one-electron redox waves due to two independently oxidized ferrocenyl groups. The spaced analogues of 2, compounds 3–5, again display only single waves corresponding to two-electron exchanged.

Cs10Tl6SiO4, Cs10Tl6GeO4, and Cs10Tl6SnO3 – First Oxotetrelate Thallides, Double Salts Containing “Hypoelectronic” [Tl6]6– Clusters

AbstractCs10Tl6TtO4 (Tt = Si, Ge) and Cs10Tl6SnO3 were synthesized by the reaction of appropriate starting materials at 623–673 K, followed by fast cooling or quenching to room temperature, in arc‐welded tantalum ampoules. According to single‐crystal X‐ray analyses, the compounds crystallize in new structure types (Cs10Tl6TtO4 (Tt = Si, Ge), P21/c and Cs10Tl6SnO3, Pnma), consisting of [Tl6]6– clusters, which can be characterized as distorted octahedra compressed along one of the fourfold axes of an originally unperturbed octahedron, and [SiO4]4–, [GeO4]4– or [SnO3]4– anions. The oxotetrelate thallides can be regarded as “double salts”, which consist of Cs6Tl6 on one side and respective oxosilicates, ‐germanates and ‐stannates on the other, showing almost not any direct interaction between the two anionic moieties, as might be expressed e.g. by the formula [Cs6Tl6][Cs4SiO4]. In contrast to the silicon and germanium compounds, where the oxidation state of the tetrel atom is unambiguously 4+, for the threefold coordinated tin atom in Cs10Tl6SnO3 an oxidation state of 2+ has to be assumed. Thus, the latter reveal further evidence that the so called “hypoelectronic” [Tl6]6– cluster does not require additional electrons and is intrinsically stable. The distortion of [Tl6]6– can be understood in terms of the Jahn–Teller theorem. According to magnetic measurements all title compounds are diamagnetic.

Monoorganotin–polyoxometal-compounds. Part IV: Na 2[( iPrSn 3)(OV) 4O 10(OH) 3]·5H 2O·3DMSO, a novel branched tetravanadate(V) stabilized by a trimeric monoorganotin-oxo-hydroxo unit

Via self-assembly of the molecular precursors sodium orthovanadate and isopropyltin-dihydroxide-chloride the unprecedented organic–inorganic hybrid polyoxoanion [( i PrSn) 3(OV) 4O 10(OH) 3] 2− was synthesized in dimethylsulfoxide (DMSO) and isolated as its sodium salt Na 2[( i PrSn) 3(OV) 4O 10(OH) 3]·5H 2O·3DMSO. This spherical nanosized anion is composed of two different structural subunits, a well-known trinuclear monoorganotin-polyoxo-hydroxo unit with octahedrally coordinated tin atoms and a new open-chain, branched isopolyoxo tetravanadate(V) with tetrahedrally coordinated vanadium atoms.

Zur Bildung einer Zinn‐Zinn‐Bindung in Bis(hexamethyldisilazyl)‐Zinn(II) unter C‐H Bindungsbruch

AbstractFormation of a Tin‐Tin‐Bond from Bis(hexamethyldisilazyl)‐Tin(II) under Fission of a C‐H BondBis(hexamethyldisilazyl)tin(II) in excess reacts with the molecular alumosiloxane (Ph2SiO)8(AlO(OH))4 to yield the well known tin(II) derivative (Ph2SiO)8(AlO2)4Sn2 and the novel bicyclic [(Me3Si)2N]Sn[N(SiMe3)SiMe2CH2]2Sn[N(SiMe3)2] containing a tin‐tin bond, which is formally related to the starting molecule by a missing hydrogen atom. From X‐ray diffraction studies on single crystals it follows that the new compound has almost C2 point symmetry (the twofold axis intersecting the tin‐tin bond) and that this tin‐tin bond is the fusion edge of anellated fivefold Sn‐Sn‐N‐Si‐C rings. The bond connecting the almost tetrahedrally coordinated tin atoms (2.737(2) Å) is astonishingly very short. This feature is also reflected in the spectroscopic data (1H, 13C, 29Si, 119Sn‐NMR) of the compound with a coupling constant 1J (117Sn/119Sn) of 9529 Hz.

Determination of the catalytically active oxidation Lewis acid sites in Sn-beta zeolites, and their optimisation by the combination of theoretical and experimental studies

Two types of Lewis acid sites are shown to exist in Sn-beta zeolite: partially hydrolysed framework tin centers ( Si O ) 3Sn OH (sites A) and fully framework coordinated tin atoms Sn( Si O ) 4 (sites B). ONIOM and DFT calculations for adsorbed acetonitrile, which is a probe molecule for Lewis acid sites, show that acetonitrile coordinates more strongly to partially hydrolysed framework Sn (sites A) in Sn-beta zeolite than to nonhydrolysed framework Sn (sites B). The corresponding IR bands associated with the ν(C N) stretching vibration were also calculated. Adsorption–desorption experiments of deuterated acetonitrile on Sn-beta give two IR bands at 2316 and 2308 cm −1 with IR shifts of 43 and 51 cm −1 with respect to gas-phase acetonitrile. These values are in excellent agreement with theoretical calculations, making it possible then to associate the Lewis sites related to 2316 and 2308 cm −1 with partially hydrolysed and nonhydrolysed framework Sn sites, respectively. Catalytic results confirm that partially hydrolysed Sn (sites A) is much more active than fully framework-integrated Sn (sites B) for Baeyer–Villiger oxidation of cyclic ketones. Finally, the ratio between these two types of sites could be influenced by postsynthesis treatments.

Synthesis and Tin(IV) Coordination Chemistry of the Novel Tripod N(CH2CH2CH2SH)3

The novel tetradentate ligand N(CH2CH2CH2SH)3, H3 - 5 was synthesized from tripropanolamine via the trichloride, subsequent reaction with potassium thioacetate and reduction with LiAlH4. Ligand H3 -5 reacts with MeSnCl3 under formation of the centrosymmetric dinuclear complex [MeSn(5)]2, 6, which was shown by X-ray structure analysis to contain two tetrahedrally coordinated tin atoms and two bridging thiolato functions.

Stability of the Anomalous Large-Void CoSn Structure

The crystal structure of CoSn represents a highly peculiar intermetallic structure type because of the presence of a large void and highly nonspherically coordinated tin atoms. Voids in crystal structures of intermetallic compounds are most unusual and always give rise to speculations whether the observed phase is the ground state or not. Here we examine this problem by means of ab initio calculations and show that the void structure of CoSn is indeed the stable phase. With pressure we predict the following sequence of structural transformations: CoSn type $\ensuremath{\rightarrow}$ FeSi type $\ensuremath{\rightarrow}$ CsCl type. The structural properties of CoSn are understood in terms of competition between covalent and metallic bonding in the system.

Tetraphenylphosphoniumtris( tetrasulfido)stannat, (PPh4)2[Sn(S4)3] / Tetraphenylphosphonium Tris-tetrasulfidostannate, (PPh4)2[Sn(S4)3

PPh4[SnCl3] reacts with Na2S4 in acetonitrile to give the title compound as one of the products. Its crystal structure was determined by X-ray diffraction (R = 0.071 for 3288 reflexions). Crystal data: monoclinic, P21/C, Z = 4, a = 1301.2(3), b = 1139.1(2), c = 3476.2(7) pm, β = 97.82(3)°· (PPh4)2[Sn(S4)3] is isotypic with (PPh4)2[Sn(Se4)3] and contains [Sn(S4)3]2- ions in which three tetrasulfido groups are chelating an octahedrally coordinated tin atom.

Synthese und Kristallstraktur von [{Cp(CO)2Fe}2Sn(F)FBF3] / Synthesis and Crystal Structure of [{Cp(CO)2Fe}2Sn(F)FBF3

Abstract [{Cp(CO)2Fe}2SnCl2] reacts with AgBF4 to form [{Cp(CO)2Fe}2Sn(F)FBF3] 1.1 crystallizes in two monoclinic modifications with a = 1018.2(4), b = 1321.1(5), c = 1364.8(5) pm, β = 104.96(4)° (1a), and a = 983.1(2), b = 1760.2(6), c = 1060.4(3) pm, β = 104.28(2)° (1b). 1a and 1b contain a nearly tetrahedrally coordinated tin atom which is bonded to two {Cp(CO)2Fe} fragments, a F atom and a BF4 group.

Zur hydrolyse von monoorganylzinn-trihalogeniden III. Isolierung und röntgenstrukturanalyse von verbindungen mit dem neuartigen käfig-ion [(i-PrSn) 12O 14(OH) 6] 2+

Single crystals of the compounds [(i-PrSn) 12O 14(OH) 6]Cl 2 · L with L = 3H 2O (I), 2DMF (II) and 4H 2O · 4DMPU (III) have been isolated and investigated by an X-ray diffraction study. Common to all is the cage cation [(i-PrSn) 12O 14(OH) 6] 2+ with a “football” like tin-oxygen framework from which the organic moieties produced. Square-pyramidally coordinated tin atoms and six-membered tin-oxygen rings with half-chair conformation are the most remarkable primary and secondary building units of this ion. The cations, anions and solvent molecules are connected by hydrogen bonds to chains in I, to a three-dimensional network in II and to isolated structure units in III.

Zur Hydrolyse von Monoorganylzinn-trihalogeniden: II. Darstellung und Struktur des i-Propylzinn-oxidhydroxid-chlorids (i-PrSn) 9O 8(OH) 6Cl 5 · 6DMSO

Single crystals of (i-PrSn) 9O 8(OH) 6Cl 5 · 6DMSO were isolated and investigated by an X-ray diffraction study. The pyramidal cage structure of the organometallic molecule is built up of trigonal bipyramidal and octahedrally coordinated tin atoms linked by μ 3-oxygen atoms or μ 2-hydroxyl groups. Individual tinoxygen bond lengths are depending on their position within the coordination polyhedra of tin. Two of the six hydroxyl groups are involved in intramolecular OH · Cl, while the rest form strong intermolecular OH · O hydrogen bonds with four dimethyl sulfoxide molecules.

Zur Hydrolyse von Monoorganylzinn-trihalogeniden: I. Molekül- und Kristallstruktur von i-Propyl- und i-Butylzinnhydroxid-dihalogenid-hydrat RSn(OH)Cl 2 · H 2O

The monoorganotin hydroxide dihalide hydrates RSn(OH)Cl 2 · H 2O with R = i-butyl and i-propyl were investigated by an X-ray diffraction study. The crystal structure consists of dimeric units with a rhombic four-membered tin oxygen ring and octahedrally coordinated tin atoms. These molecules are bonded by OH ... Cl hydrogen bridges to chains which are linked to layers.