Heterotermetallic indium lithium halostannates: low-temperature single-source precursors for tin-rich indium tin oxides and their application for thin-film transistors

The syntheses and structural elucidation of dimeric [Sn(OCyHex)(2)] (1), its corresponding (cyclohexoxy)alkalistannates(II) [{M(OCyHex)(3)Sn}(2)] (M = Li (2), Na (3), K (4)), and of the first heteroleptic heterotermetallic Li/In/Sn-haloalkoxide clusters [X(2)In{LiSn(2)(OCyHex)(6)}] (X = Br (5), Cl (6)) with a double seco-norcubane core are reported. They represent suitable precursors for new amorphous indium tin oxide (ITO) materials as transparent conducting oxides with drastically reduced concentrations of expensive indium, while maintaining their high electrical performance. In fact, compounds 5 and 6 were successfully degraded under dry synthetic air at relatively low temperature, resulting in new semiconducting tin-rich ITOs homogeneously dispersed in a tin oxide/lithium oxide matrix. The obtained particles were investigated and characterised by different analytical techniques, such as powder XRD, IR spectroscopy, SEM, TEM and energy-dispersive X-ray spectroscopy (EDX). The analytical data confirm that the final materials consist of tin-containing indium oxide embedded in an amorphous tin oxide matrix. The typical broadening and shift of the observed indium oxide reflections to higher 2θ values in the powder XRD pattern clearly indicated that tin centres were successfully incorporated into the In(2)O(3) lattice and partially occupied In(3+) sites. Investigations by EDX mapping proved that Sn was homogeneously distributed in the final materials. Thin-film field-effect transistors (FETs) were fabricated by spin-coating of silicon wafers with solutions of 5 in toluene and subsequent calcination under dry air (25-700?°C). The FETs prepared with precursor 5 exhibited excellent performances, as shown by a charge-carrier mobility of 6.36×10(-1) cm(2) V(-1) s (calcination at 250?°C) and an on/off current ratio of 10(6).     

Chemical‐Bath‐Deposited Indium Oxide Microcubes for Solar Water Splitting

We fabricated films of cubic indium oxide (In₂O₃) by chemical bath deposition (CBD) for solar water splitting. The fabricated films were characterized by X‐ray diffraction analysis, Raman scattering, X‐ray photoelectron spectroscopy, and scanning electron microscopy, and the three‐dimensional microstructure of the In₂O₃ cubes was elucidated. The CBD deposition time was varied, to study its effect on the growth of the In₂O₃ microcubes. The optimal deposition time was determined to be 24 h, and the corresponding film exhibited a photocurrent density of 0.55 mA cm^?2. Finally, the film stability was tested by illuminating the films with light from an AM 1.5 filter with an intensity of 100 mW cm^?2.     

Synthese und Charakterisierung von InIII–SnII‐Halogenido‐Alkoxiden und von Indiumtri‐tert‐butoxid

Synthesis and Characterization of In^III–Sn^II‐Halogenido‐Alkoxides and of Indiumtri‐ tert ‐butoxide Through sodium halide elimination between Indium(III) halides and sodium‐tri‐tert‐butoxistannate(II) or sodium‐tri‐tert‐butoxigermanate(II) the three new heterometallic and heteroleptic alkoxo compounds THF · Cl₂In(OtBu)₃Sn ( 1 ), THF · Br₂In(OtBu)₃Sn ( 2 ), and THF · Cl₂In‐ (OtBu)₃Ge ( 3 ), have been synthesized. The molecular structures of 1 and 2 in the solid state follow from single crystal X‐ray structure determinations while structural changes in solution may be derived from temperature dependant NMR spectroscopy. The crystal structures of compounds 1 and 2 are despite different halide atoms isostructural. Both crystallize in the ortho‐rhombic crystal system in space group Pbca with eight molecules per unit cell. The heavy atoms occupy the apical positions of empty trigonal bipyramids of almost point symmetry C_s(m) and are connected through oxygen atoms occupying the equatorial positions. The indium atoms in both compounds are in the centers of distorted octahedra from 4 oxygen and 2 halogen atoms whereas the tin atoms are coordinated by three oxygen atoms in a trigonal pyramidal fashion. Although the coordinative bonding of THF to indium leads to an asymmetry of the molecule the NMR spectra in solution are simple showing a more complex pattern at lower temperatures. Tri(tert‐butoxi)indium [In(OtBu)₃]₂ ( 4 ), is obtained through alcoholysis of In(N(Si(CH₃)₃)₂)₃ using tert‐butanol in toluene and is crystallized from hexane. The X‐ray structure determination of 4 seems to be the first one of a homoleptic and homometallic indiumalkoxide. Compound 4 crystallizes in the monoclinic crystal system in a dimeric form with eight molecules in the unit cell of space group C2/c. The dimeric units have C₂ symmetry and an almost planar In₂O₂ ring which originates from oxygen bridging of the monomers. Through this mutual Lewis acid base interaction the indium atoms get four oxygen ligands in a distorted tetrahedral environment.     

Indium oxide co-doped with tin and zinc: A simple route to highly conducting high density targets for TCO thin-film fabrication

Indium oxide co-doped with tin and zinc (ITZO) ceramics have been successfully prepared by direct sintering of the powders mixture at 1300 °C. This allowed us to easily fabricate large highly dense target suitable for sputtering transparent conducting oxide (TCO) films, without using any cold or hot pressing techniques. Hence, the optimized ITZO ceramic reaches a high relative bulk density (∼ 92% of In₂O₃ theoretical density) and higher than the well-known indium oxide doped with tin (ITO) prepared under similar conditions. All X-ray diagrams obtained for ITZO ceramics confirms a bixbyte structure typical for In₂O₃ only. This indicates a higher solubility limit of Sn and Zn when they are co-doped into In₂O₃ forming a solid-solution. A very low value of electrical resistivity is obtained for [In₂O₃:Sn_0.10]:Zn_0.10 (1.7 × 10⁻³ Ω cm, lower than ITO counterpart) which could be fabricated to high dense ceramic target suing pressure-less sintering.     

Semihydrogenation of Acetylene on Indium Oxide: Proposed Single‐Ensemble Catalysis

Indium oxide catalyzes acetylene hydrogenation with high selectivity to ethylene (>85 %); even with a large excess of the alkene. In situ characterization reveals the formation of oxygen vacancies under reaction conditions, while an in depth theoretical analysis links the surface reduction with the creation of well‐defined vacancies and surrounding In₃O₅ ensembles, which are considered responsible for this outstanding catalytic function. This behavior, which differs from that of other common reducible oxides, originates from the presence of four crystallographically inequivalent oxygen sites in the indium oxide surface. These resulting ensembles are 1) stable against deactivation, 2) homogeneously and densely distributed, and 3) spatially isolated and confined against transport; thereby broadening the scope of oxides in hydrogenation catalysis.     

Neue molekulare Indium‐Zinn‐Sauerstoff‐ und Indium‐Zinn‐Natrium‐Sauerstoff‐Chlor‐Cluster

Abstract. The five‐membered heteroelement cluster THF · Cl₂In(O^tBu)₃Sn reacts with the sodium stannate [Na(O^tBu)₃Sn]₂ to produce either the new oxo‐centered alkoxo cluster ClInO[Sn(O^tBu)₂]₃ ( 1 ) (in low yield) or the heteroleptic alkoxo cluster Sn(O^tBu)₃InCl₃Na[Sn(O^tBu)₂]₂ ( 2 ). X‐ray diffraction analyses reveal that in compound 1 the polycyclic entity is made of three tin atoms which together with a central oxygen atom form a trigonal, almost planar triangle, perpendicular to which a further indium atom is connected through the oxygen atom. The metal atoms thus are arranged in a Sn₃In pyramid, the edges of which are all saturated by bridging tert‐butoxy groups. The indium atom has a further chloride ligand. Compound 2 has two trigonal bipyramids as building blocks which are fused together at a six coordinate indium atom. One of the bipyramids is of the type SnO₃In with tert‐butyl groups on the oxygen atoms, while the other has the composition InCl₃Na with chlorine atoms connecting the two metals. The sodium atom in 2 has further contacts to two plus one alkoxide groups which are part of a[Sn(O^tBu)₂]₂ dimer disposing of a Sn₂O₂ central cycle. The hetero element cluster in 2 thus combines three closed entities and its skeleton SnO₃InCl₃NaO₂Sn₂O₂ consists of three different metallic and two different non‐metallic elements.     

Synthesis,structure and property of diorganotin N‐[(3‐methoxy‐2‐oxyphenyl)methylene]tyrosinates

Five new diorganotin N‐[(3‐methoxy‐2‐oxyphenyl)methylene] tyrosinates, R₂Sn[2‐O‐3‐MeOC₆H₃CH=NCH (CH₂C₆H₄OH‐4)COO] (R = Me, 1 ; Et, 2 ; Bu, 3 ; Cy, 4 ; Ph, 5 ), have been synthesized and characterized by elemental analysis, IR, NMR (¹H, ¹³C and ¹¹⁹Sn) spectra, and the X‐ray single crystal diffraction. In non‐coordinated solvent, complexes 1 – 5 have penta‐coordinated tin atom. In the solid state, 1 – 3 are centrosymmetric dimmers in which each tin atom is seven‐coordinated in a distorted pentagonal bipyramid, and 4 displays discrete molecular structure with distorted trigonal bipyramidal geometry, and the tin atom of 5 is hexa‐coordinated and possess the distorted octahedral geometry with a coordinational methanol molecule. The intermolecular O‐H???O hydrogen bonds in 1 – 4 link molecules into the different one‐dimensional supramolecular chain with R₂² (30) or R₂² (20) macrocycles, and the molecules of 5 are joined into a two‐dimensional supramolecular network containing R₄⁴ (24) and R₄⁴ (28) two macrocycles. Bioassay results against human tumour cell HeLa indicated that 3 ‐ 5 belonged to the efficient cytostatic agents and the activity decreased in the order 4 > 3 > 5 > 2 > 1. The fluorescence determinations show the complexes may be explored for potential luminescent materials.     

Non‐Innocent Ligand Effects on Low‐Oxidation‐State Indium Complexes

Attempts to coordinate neutral ligands to low oxidation state indium centers are often hindered by disproportionation pathways that produce elemental indium and higher oxidation state species. In contrast, we find that reactions of the salt, InOTf (OTf=trifluoromethanesulfonate), with α‐diimine ligands yielded intensely colored compounds with no evidence of decomposition. X‐ray structural analysis of InOTf ? ^MesDAB^Me (^MesDAB^Me=N,N‐dimesityl‐2,3‐dimethyl‐diazabutadiene; 1 ) reveals a discrete molecular compound with a pyramidal coordination environment at the indium center, consistent with the presence of a stereochemically active lone pair of electrons on indium and a neutral diazabutadiene chelate ligand. The use of the less‐electron‐rich ^MesDAB^H ligand (^MesDAB^H=N,N‐dimesityl‐diazabutadiene) engenders dramatically different reactivity and produces a metallopolymer (InOTf ? ^MesDAB^H)_∞ ( 2 ) linked via C? C and In? In bonds. The difference in reactivity is rationalized by cyclic voltammetry and DFT studies that suggest more facile electron transfer from In^I to the ^MesDAB^H and bis(aryl)acenaphthenequinonediimine (BIAN) ligands. Solution EPR spectroscopy indicates the presence of non‐interacting ligand‐based radicals in solution, whereas solid‐state EPR studies reflect the presence of a thermally accessible spin triplet consistent with reversible C? C bond cleavage.     

Electrochemical Cholesterol Sensor Based on Tin Oxide‐Chitosan Nanobiocomposite Film

A chitosan (CS)‐tin oxide (SnO₂) nanobiocomposite film has been deposited onto an indium‐tin‐oxide glass plate to immobilize cholesterol oxidase (ChOx) for cholesterol detection. The value of the Michaelis–Menten constant (K_m) obtained as 3.8 mM for ChOx/CS‐SnO₂/ITO is lower (8 mM) than that of a ChOx/CS/ITO bioelectrode revealing enhancement in affinity and/or activity of ChOx towards cholesterol and also revealing strong binding of ChOx onto CS‐SnO₂/ITO electrode. This ChOx/CS‐SnO₂/ITO cholesterol sensor retains 95% of enzyme activity after 4–6 weeks at 4 °C with response time of 5 s, sensitivity of 34.7 μA/mg dL^?1 cm² and detection limit of 5 mg/dL.     

Vapor Composition over Solid Indium Trichloride and in ­Indium Chloride Unsaturated Vapor

The dependence of indium trichloride saturated and unsaturated vapor pressure on temperature was studied in the range of 630–950 K by static methods using a quartz membrane zero‐manometer and taking into account the volume of its working chamber and substance mass. The thermodynamic data on the process of dissociation of dimeric molecules and sublimation of monomer and dimer from solid indium trichloride were calculated: ΔH⁰_subl InCl₃(g)₂₉₈ = 155.3 ± 6.2 kJ · mol^–1; ΔS⁰_subl InCl₃(g)₂₉₈ = 199.5 ± 7.9 J · mol^–1 · K^–1; ΔH⁰_subl In₂Cl₆(g)₂₉₈ = 159.3 ± 6.2 kJ · mol^–1; ΔS⁰_subl In₂Cl₆(g)₂₉₈ = 207.1±3.8 J · mol^–1 · K^–1; ΔH⁰_dis In₂Cl₆(g)₂₉₈ = 152.6 ± 5.5 kJ · mol^–1 and ΔS⁰_dis In₂Cl₆(g)₂₉₈ = 171.6 ± 5.2 J · mol^–1 · K^–1. The saturated vapor over solid indium trichloride consists mainly of a mixture of monomeric and dimeric molecules (InCl₃ and In₂Cl₆), and the content of the latter is slightly growing with increasing temperature.     

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.     

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,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.     

High‐Pressure Synthesis and Single‐Crystal Structure Elucidation of the Indium Oxide‐Borate In4O2B2O7

The indium oxide‐borate In₄O₂B₂O₇ was synthesized under high‐pressure/high‐temperature conditions at 12.5 GPa/1420 K using a Walker‐type multianvil apparatus. Single‐crystal X‐ray structure elucidation showed edge‐sharing OIn₄ tetrahedra and B₂O₇ units building up the oxide‐borate. It crystallizes with Z = 8 in the monoclinic space group P2₁/n (no. 14) with a = 1016.54(3), b = 964.55(3), c = 1382.66(4) pm, and β = 109.7(1)°. The compound was also characterized by powder X‐ray diffraction and vibrational spectroscopy.     

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.     

[5‐Bromo‐N‐(2‐carboxylatophenyl)salicylideniminato]dimethyltin(IV)

The structure of the title di­methyl­tin(IV) complex, [2‐(5‐bromo‐2‐oxido­benzyl­idene­amino)­benzoato‐κ³O,N,O′]di­methyl­tin(IV), [Sn(CH₃)₂(C₁₄H₈BrNO₃)], features centrosymmetric dimers disposed about a central Sn₂O₂ core. Each Sn centre has seven‐coordinate pentagonal–bipyramidal geometry, taking into account two moderately long Sn—O contacts about an inversion centre [2.679 (4) and 2.981 (4) Å]. The methyl groups are in an axial orientation.     

Dihalodimethyltin(IV) complexes of 2‐(pyrazol‐1‐ylmethyl)pyridine

Reaction of dichloro‐ and dibromodimethyltin(IV) with 2‐(pyrazol‐1‐ylmethyl)pyridine (PMP) afforded [SnMe₂Cl₂(PMP)] and [SnMe₂Br₂(PMP)] respectively. The new complexes were characterized by elemental analysis and mass spectrometry and by IR, Raman and NMR (¹H, ¹³C) spectroscopies. Structural studies by X‐ray diffraction techniques show that the compounds consist of discrete units with the tin atom octahedrally coordinated to the carbon atoms of the two methyl groups in a trans disposition (Sn? C = 2.097(5), 2.120(5) Å and 2.110(6), 2.121(6) Å in the chloro and in the bromo compounds respectively), two cis halogen atoms (Sn? Cl = 2.4908(16), 2.5447(17) Å; Sn? Br = 2.6875(11), 2.7464(9) Å) and the two donor atoms of the ligand (Sn? N = 2.407(4), 2.471(4) Å and 2.360(5), 2.455(5) Å). In both cases, the Sn? N(pyridine) bond length is markedly longer than the Sn? N(pyrazole) distance. Copyright © 2003 John Wiley & Sons, Ltd.     

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     

Coordination polymers based on building blocks of dimethyltin(IV) Chloride iso‐thiocyanate and dimethyltin(IV) di‐iso‐thiocyanate with pyrazine‐2‐carboxylate and 4, 4′‐bipyridine

The reaction of 4,4′‐bipy with dimethyltin(IV) chloride iso‐thiocyanate affords the one‐dimensional (1D) coordination polymer, [Me₂Sn(NCS)Cl·(4,4′‐bipy)]_n ( 1 ), whereas reaction of dimethyltin(IV) dichloride with sodium pyrazine‐2‐carboxylate in the presence of potassium iso‐thiocyanate affords the two‐dimensional (2D) coordination polymer, {[Me₂Sn(C₄H₃N₂COO)₂]₂ [Me₂Sn(NCS)₂]}_n ( 2 ). Both coordination polymers were characterized by elemental analysis and infrared spectroscopy in addition to ¹H and ¹³C NMR spectroscopy of the soluble coordination polymer ( 1 ). A single‐crystal structure determination showed that the asymmetric unit in 1 contains Me₂Sn(NCS)Cl and 4,4′‐bipy moieties and a 1D infinite rigid chain structure forms through bridging of the 4,4′‐bipy ligand between tin atoms and the geometry around the tin atom is a distorted octahedral. Coordination polymer 2 contains two distinct tin atom geometrics in which one tin atom is seven coordinate, and the other is six coordinate. The two tin atom environments are best described as a pentagonal bipyramidal in the former and distorted octahedral in the latter where the carboxylate groups bridge the two tin atoms and construct a 2D‐coordination polymer. The ¹¹⁹Sn NMR spectroscopy indicates the octahedral geometry of 1 retains in solution. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:699–706, 2011; View this article online at wileyonlinelibrary.com . DOI 10.1002/.20736     

Synthesis and Reactivity of Low‐Valent Group 14 Element Compounds

The tetravalent germanium and tin compounds of the general formulae Ph*EX₃ (Ph* = C₆H₃Trip‐2,6, Trip = C₆H₂iPr₃‐2,4,6; E = Sn, X = Cl ( 1a ), Br ( 1b ); E = Ge, X = Cl ( 2 )) are synthesized by reaction of Ph*Li·OEt₂ with EX₄. The subsequent reaction of 1a , b with LiP(SiMe₃)₂ leads to Ph*EP(SiMe₃)₂ (E = Sn ( 3 ), Ge ( 4 )) and the diphosphane (Me₃Si)₂PP(SiMe₃)₂ by a redox reaction. In an alternative approach 3 and 4 are synthesized by using the corresponding divalent compounds Ph*ECl (E = Ge, Sn) in the reaction with LiP(SiMe₃)₂. The reactivity of Ph*SnCl is extensively investigated to give with LiP(H)Trip a tin(II)‐phosphane derivative Ph*SnP(H)Trip ( 6 ) and with Li₂PTrip a proposed product [Ph*SnPTrip]^– ( 7 ) with multiple bonding between tin and phosphorus. The latter feature is confirmed by DFT calculations on a model compound [PhSnPPh]^–. The reaction with Li[H₂PW(CO)₅] gives the oxo‐bridged tin compound [Ph*Sn{W(CO)₅}(μ‐O)₂SnPh*] ( 8 ) as the only isolable product. However, the existence of 8 as the bis‐hydroxo derivative [Ph*Sn{W(CO)₅}(μ‐OH)₂SnPh*] ( 8a ) is also possible. The Sn^IV derivatives Ph*Sn(OSiMe₃)₂Cl ( 9 ) and [Ph*Sn(μ‐O)Cl]₂ ( 10 ) are obtained by the oxidation of Ph*SnCl with bis(trimethylsilyl)peroxide and with Me₃NO, respectively. Besides the spectroscopic characterization of the isolated products compounds 1a , 2 , 3 , 4 , 8 , and 10 are additionally characterized by X‐ray diffraction analysis.