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A series of six new organotin(IV) compounds, namely, [nPr3Sn(HL)(MeOH)] 1, [nBu3Sn(HL)]n 2, [Bz3Sn(HL)]n 3, [Ph3Sn(HL)]n⋅nC6H6 4, [Ph3Sn(HL)(EtOH)] 5 and [nBu2Sn(L)]n 6 were synthesized by reacting appropriate tri- and di-organotin(IV) precursors with the flexible pro-ligand 5-[(E)-2-(4-pyridyl)-1-diazenyl]-2-hydroxybenzoic acid. Their solid-state structures were deduced from single crystal X-ray diffraction data and, in the case of compound 6, also by solid-state 13C and 119Sn NMR spectroscopy. Compounds 1 and 5 are mononuclear as a consequence of methanol/ethanol coordination preventing the propagation of the polymers. The monodentate oxygen atom from the carboxylate group of HL− and the tin-coordinated oxygen atom of alcohol are situated at the axial positions, while Sn-R substituents are at the equatorial sites, defining the distorted trigonal-bipyramidal coordination polyhedron. Both 1 and 5 form one-dimensional (1D) chains created by virtue of O−Hsolv⋯Npy hydrogen bonding interactions, and antiparallel running chains in 1 furnish 34-membered dinuclear macrocyclic rings occupied by SnPr3 groups. Compounds 2–4 feature a one-dimensional coordination polymer facilitated by intermolecular N→Sn bond formation with the pyridyl substituent of LH−. The axially located OOCO and Npy donor atoms and equatorial Sn-R groups give rise to a trigonal-bipyramidal geometry. While similar coordination geometries are observed for 2–4, the tri-n-butyl derivative 2 generates 60-membered macrocyclic rings where four n-butyl groups from two neighboring molecules occupy the cavities. The triphenyltin analogue 4 forms two-dimensional layers with voids filled by benzene solvate molecules, and the sterically demanding tribenzyltin groups in compound 3 result in only relatively weak C−H⋯π, C−H⋯N and van der Waals contacts. On the other hand, compound 6 is a two-dimensional (2D) coordination polymer displaying a distorted pentagonal-bipyramidal geometry around the tin atom where four oxygen atoms of two ligand molecules and the nitrogen atom of a ligand constitute the equatorial plane, while the carbon atoms of the n-butyl groups complete the axial positions. The molecules of 6 self assembled to an interesting dimeric tecton based on a four-membered Sn2O2 ring, generating large 48-membered hexanuclear macrocycles, where the cavities are filled by four di-n-butyl groups from two neighboring molecules. The solution behaviors of compounds 1–5 were judged from the results of the 119Sn NMR spectroscopic characterization.

Reaction of sodium 2-((E)-((Z)-4-hydroxypent-3-en-2-ylidene)amino)succinate and sodium (E)-2-((1-(2-hydroxyphenyl)ethylidene)amino)succinate (L1HNa2 and L2HNa2) in a 1:2 M ratio with Bz2SnCl2 in methanol gave dinuclear diorganotin(IV) complexes of composition [Bz2Sn(Lx)SnBz2Cl] (Lx = L1 (1) and L2 (2)). Reaction of L2HNa2 and Bz3SnCl (1:2) in anhydrous toluene under reflux conditions yielded the analogous chlorine-free product of composition [Bz2Sn(L2)SnBz3] (3) via cleavage of a Sn-C bond for one of the triorganotin precursor equivalents with elimination of toluene. In addition, the tributyltin(IV) compounds of composition [Bu3Sn(LxH)SnBu3] (Lx = L2 (4) and L3 (5)) were prepared in a single-step transformation by combining equimolar proportions of (Bu3Sn)2O, (S)-2-aminosuccinic acid and 2'-hydroxyacetophenone/2-hydroxybenzaldehyde in anhydrous methanol. The structures of the organotin(IV) compounds in solution were assessed using 1H, 13C and 119Sn NMR spectroscopic techniques, while the molecular structures of 1–5 were analyzed by single-crystal X-ray diffraction. In the solid state, complexes 1-3 exhibit one-dimensional coordination polymers with alternate six- and seven-coordinate tin atoms embedded in distorted monocapped trigonal-bipyramidal (1-2)/octahedral (3) and pentagonal-bipyramidal (1-2)/bicapped trigonal-bipyramidal (3) coordination environments. On the contrary, compounds 4–5 are two-dimensional coordination polymers based on 30-membered tetranuclear macrocyclic ring structures, in which the tin atoms comprise distorted trigonal-bipyramidal coordination polyhedra. However, in solution the polymeric structures of 1–5 dissociate to give dinuclear complexes, even in non-coordinating solvents such as chloroform.

A series of diamondoid-decorated organotin(IV) derivatives of composition Me3Sn(L1) (1), Ph3Sn(L1) (2), {[Me2Sn(L1)]2O}2 (3), [BzSn(O)(L1)]6 (4), Me3Sn(L2)OH2 (5), [Ph3Sn(L2)]n (6), Bu2Sn(L2)2 (7), Bz2Sn(L2)2OH2 (8) and [BzSn(O)(L2)]6 (9) were prepared by reacting appropriate organotin(IV) precursors with either acid forms of the pro-ligands adamantane-1-carboxylic acid (HL1) and 2-(adamantan-1-yl)acetic acid (HL2) or their sodium salts. Compounds 1–9 were characterised by spectroscopic techniques, including 119Sn NMR in non-coordinating solvent for assessment of the solution-state structures. The molecular and crystal structures of 2–8 were established by X-ray crystallography. The packing is largely dictated by hydrophobic interactions with the exception in the crystals of 6, where Sn…O secondary bonding is apparent, and in each of 5 and 8 where O–H…O hydrogen bonding is present leading to a two-dimensional array and zig-zag chains, respectively. The organotin compounds were evaluated for their anti-bacterial activity against 15 human bacterial pathogens. Based on disc diffusion and minimum inhibitory concentration assays, the two triphenyltin species, 2 and 6, and di-n-butyl species, 7, are effective against both Gram-positive and Gram-negative bacteria, including methicillin resistant Staphylococcus aureus (MTCC 381123) and Shigella flexneri (ATCC 12022), a causative agent for shigellosis. Time-kill assays showed that 2 and 6 had both time- and concentration-dependant anti-bacterial effects against susceptible bacteria. Cell viability assays showed that 2 and 6 were moderately toxic to a normal cell line, that is, human embryonic kidney 293T (HEK293T).

Six new bicycloazastannoxides of compositions [Me2Sn(L1H)] (1), [nBu2Sn(L1H)] (2), [Ph2Sn(L1H)] (3), [Bz2Sn(L1H)] (4), [Me2Sn(L2H)(MeOH)]·MeOH (5) and [Ph2Sn(L3H)] (6), where L1H = 2-((E)-((Z)-4-hydroxypent-3-en-2-ylidene)amino)-3-(4-hydroxyphenyl)propanoate, L2H = (E)-2-((2-hydroxybenzylidene)amino)-3-(4-hydroxyphenyl)propanoate and L3H = (E)-3-(4-hydroxyphenyl)-2-((1-(2-hydroxyphenyl)ethylidene)amino)propanoate, were synthesized and spectroscopically characterized. The 1H and 13C NMR spectra of compounds 1–6 displayed two sets of signals for Sn-R2 (R = Me, nBu, Ph and Bz) indicating a diastereotopic environment according to the asymmetric nature of the ligand. The 119Sn NMR data of the compounds in CDCl3 indicate five-coordinate tin atoms, showing that the bicycloazastannoxide assemblies remain intact as observed in the solid-state structures. The crystal structures of 1–6 revealed discrete molecular structures in all cases with distorted trigonal-bipyramidal geometries for 1–4 and 6, and a strongly distorted six-fold coordination for 5 due to association of a MeOH solvent molecule. At the supramolecular level, the molecular structures in 1–4 and 6 are linked either through double-bridged O-H⋯O/C-H⋯O synthons (1 and 6) or single O-H⋯O hydrogen bonds (2–4). The resulting 1D helical strands exhibit varying Sn⋯Sn distances due to the different molecular conformations. The molecules in 5 associate to dimers through two Sn⋯O and O-H⋯O interactions, which are further connected via O-H⋯O hydrogen bonds to give 1D strands containing 22-membered macrocycles.

The reaction of tellurium tetrahalides, TeX4 (X Cl. Br) with acetyltrimethylsilane in CCl4 at ambient temperature, unlike that of the aryltellurium trichlorides, ArTeCl3 that give the expected electrophilic substitution products, Ar(Me3SiCOCH2)TeCl2, (Ar = 1-C10H7, 2; 2,4,6-Me3C6H2, 3), afforded novel silylated heterocycles, 3-methyl-5-(trimethylsilyl)-1,2-oxatellurol-1-ium halides 1a and 1b. These Te(II) heterocyclic compounds undergo halide exchange with sodium iodide and also add dihalogens oxidatively to afford the corresponding iodide, 1c and the Te(IV) trihalides, 5a and 5b respectively. A large lowering of ν(CO) is indicative of strong Te⋯O C interactions among these heterocycles, and is also substantiated by single-crystal X-ray diffraction data for 3-methyl-5-(trimethylsilyl)-1,2-oxatellurol-1-ium chloride. The 125Te chemical shifts for the new 10-Te-3 telluranes and 12-Te-5 pertelluranes that involve tellurium bound to two highly electronegative atoms (O, X) are among the highest (downfield) reported for organotellurium(II) and (IV) compounds.

Synthesis and complete characterization of some ester functionalized vinylic tellurides bearing an aryl ligand with varying steric and electronic effects bound to tellurium is described. Hydrotelluration of methyl propiolate using Ar2Te2/NaBH4 in methanol results in a mixture of stereoisomers of methyl β-(aryltelluro)acrylates, ArTeCHCHCOOMe (Ar = 4-MeOC6H4, 1A; 1-C10H7, 2A; 2,4,6-Me3C6H2, 3A; C5H5FeC5H4, 4A; 4-Me2NC6H4, 5A; and 2-C4H3S, 6A). The same reaction in ethanol provides isomeric mixtures of the ethyl esters ArTeCHCHCOOEt (1B–6B). However, in the reactions between methyl propiolate and Ar2Te2 (Ar = 2,4,6-Me3C6H2, 4-Me2NC6H4) in isopropanol or t-butanol, no exchange of alkyl groups between the parent ester and the solvent is observed, instead detelluration of the Ar2Te2 to Ar2Te is a competing reaction along with almost exclusive formation of the (Z)-isomers (3Aa, 5Aa). The geometry of the separated stereoisomers is established in solution, with the help of 1H, 13C and 125Te NMR spectrometry. Of particular interest is the observation that 125Te chemical shifts {deshielded in (Z) compared to (E); Δδ = 106–136 ppm} and the geminal heteronuclear coupling constants {2J(1H–125Te) values for (E) are more than seven times that of the corresponding (Z) isomer} can be used to distinguish between liquid isomers. Structural characterization in the solid state by single-crystal X-ray diffraction for the 2Ba, 3Aa, 3Ba, 5Aa, 8 (Z)-isomers as well as for both stereoisomers of 4-Me2NC6H4TeCHCHCOOEt (5Ba and 5Bb) is also presented. The carbonyl O atom of the ester group is invariably involved, at least in the solid state, in a secondary bonding interaction with the Te(II) atom. While an intermolecular Te⋯O interaction gives rise to one-dimensional supramolecular arrays in the crystal lattice of 5Bb with (E) configuration, it is realized intramolecularly in the case of the (Z)-isomers due to the cis position of the chalcogen atoms.

Five new diorganotin(IV) compounds were prepared by reacting diorganotin dichlorides R 2 SnCl 2 (R = Me, n Bu and Ph) with sodium salts of the tridentate NO 2 ligands ( E )-3-hydroxy-2-((2-hydroxybenzylidene)amino)propanoic acid (L 1 H 2 Na) and ( E )-3-hydroxy-2-((1-(2-hydroxyphenyl)ethylidene)amino)propanoic acid (L 2 H 2 Na). The molecular structures of the resulting diorganotin (IV) compounds have been established by elemental analysis and a combination of IR and NMR ( 1 H, 13 C, 119 Sn) spectroscopy. In all cases, the 119 Sn NMR chemical shifts were indicative of five-coordinate tin atoms in solution. However, investigation of compounds [Me 2 SnL 1 H]·H 2 O ( 1 ), [Ph 2 SnL 1 H]·2C 6 H 6 ( 3 ), [Me 2 SnL 2 H]·CHCl 3 ( 4 ) and [Ph 2 SnL 2 H] ( 5 ) by single-crystal X-ray diffraction revealed that only compound 3 has a distorted trigonal–bipyramidal geometry in the solid state. For compounds 1 , 4 and 5 the coordination geometries are distorted octahedral, either due to intermolecular association through Sn⋯O interactions ( 1 ) or coordination through the oxygen atom from the pendant CH 2 OH group ( 4 and 5 ). At the supramolecular level, the molecular structures are linked through O–H⋯O hydrogen bonds to give discrete dimeric assemblies ( 4 ), 1D chains ( 3 , 5 ) and 2D hydrogen bonded layers ( 1 ).

Chloro analogs of novel organotellurium(IV) compounds (1a, 2Aa, 2Ba, 3Aa & 3Ba) have been synthesized by using electrophilic substitution reactions. The 2-pyridoylmethyltellurium(IV) trichloride, PyCOCH2TeCl3; 1a (Py = 2-C5H4N, 1) has been prepared by the condensation reaction between the parent methyl ketone (PyCOCH3) and TeCl4. Aryl(2-pyrrolylmethyl)tellurium(IV) dichlorides, Ar(PyrrCOCH2)TeCl2; 2Aa, 2Ba (Pyrr = 2-C4H4N, 2; Ar = 1-C10H7, Npl, A; 2,4,6-Me3C6H2, Mes, B) and aryl(2-oxocyclohexyl)tellurium(IV) dichlorides, Ar(Cyl)TeCl2; 3Aa, 3Ba (Cyl = 2-C6H9O, 3) have been prepared by electrophilic substitution reaction of NplTeCl3 or MesTeCl3 with 2-acetylpyrrole and cyclohexanone respectively. Formation of tellurium(IV) trichloride (PyCOCH2TeCl3, 1a) corresponds to a category of compound which are rarely obtained using this methodology. Structural aspects of Te(IV) compounds 1a, 2Ba and 3Ba have been studied using single crystal X-ray diffraction technique. Crystallographic studies of 1a has indicated a preference of the 2-pyridoylmethyl moiety for the small-bite (C, N) chelation resulting in the 1,5 Te⋯N hypervalent interaction while in PyrrCOCH2MesTeCl2, 2Ba; 2-pyrrolylmethyl moiety (C, O) chelation over less strained (C, N) coordination is preferred. In 3Ba, 1,4 Te⋯O intramolecular secondary bonding interaction (SBI) has appeared.

Oxidative addition of α-bromo-3-acetyl-2,5-dimethylthiophene to elemental tellurium and aryltellurium(II) bromide provides direct routes to (2,5-dimethyl-3-thiophenoylmethyl)tellurium(IV) dibromides, (Me2TpnCOCH2)2TeBr2 (1a; Me2Tpn = 2,5-Me2-3-C4HS) and Ar(Me2TpnCOCH2)TeBr2 (Ar = 1-C10H7, Npl, 2a; 2,4,6-Me3C6H2, Mes, 3a). The chloro analogs of 2a and 3a, Ar(Me2TpnCOCH2)TeCl2 (Ar = Npl, 2b; Mes, 3b) and derivative when Ar = Anisyl (anisyl = 4-MeOC6H4, 4b) were prepared by the condensation reaction of methyl ketone, Me2TpnCOCH3 with NplTeCl3, MesTeCl3 and anisylTeCl3 respectively while the chloro analog of 1a, bis(2,5-dimethyl-3-thiophenoylmethyl)tellurium(IV) dichloride, (Me2TpnCOCH2)2TeCl2 (1b) was obtained by the condensation reaction of methyl ketone, Me2TpnCOCH3 with TeCl4. Metathesis of these products (1a–b, 2a–b, 3a–b and 4b) with an alkali iodide affords the iodo analogs 1c, 2c, 3c and 4c. These diorganotellurium dihalides are reduced with aqueous bisulfite to diorganotellurides 1–4, which can be oxidized readily with dihalogens to the desired diorganotellurium(IV) dihalides. The crystal structures of the Te(IV) compounds 1b, 2a, 3c and 4b have been studied and all the Te(IV) compounds, the carbonyl functionalized organic moiety, show intramolecular 1,4–Te⋯O secondary bonding interaction (SBI). In the crystal lattice of 2a, the intermolecular Te⋯Br secondary bonding interactions are evident and result in a dimer. They get further associated via C–H⋯Br secondary interactions to form a 3D supramolecular motifs. In 1b, 3c and 4b supramolecular motifs are formed through C–H⋯O and C–H⋯Cl interactions.

Methyl and t-butyl esters of α-bromoacetic acid added oxidatively to elemental tellurium in the presence of sodium iodide to give high yields of crystalline bis(alkoxycarbonylmethyl)tellurium(IV) diiodides, (ROCOCH2)2TeI2. The chloro and bromo analogs were prepared via their reduction into tellurides followed by dihalogen oxidation. Activation of the α-Csp3–Br bond by ester functionality appears to be insufficient as methyl α-bromoacetate failed to add to Te(0) or aryltellurium(II) bromides. The nucleophilic substitution reaction of α-bromoesters with aryltellurolates, ArTe−Na+ (Ar = 1-C10H7, Np; 2,4,6-Me3C6H2, Mes), gave (alkoxycarbonylmethyl)aryltellurides that were characterized as mixed diorganotellurium dihalides. Crystal structures of Np(MeOCOCH2)TeBr2, Mes(MeOCOCH2)TeBr2 and Mes(t-BuOCOCH2)TeCl2 show that the functionalized organic moiety, ROCOCH2, behaves as a (C, O) chelating ligand. The carbonyl O atom of the ester group in these compounds is involved in a 1,4-Te⋯O secondary bonding interaction. However, the functionalized ligands in the case of (MeOCOCH2)2TeI2 are devoid of such an interaction. Surprisingly, one of the two organic ligands in (MeOCOCH2)2TeBr2 takes part in an intramolecular 1,4-Te⋯O interaction, the other appears to involve an intermolecular Te⋯O interaction to result in a one-dimensional array of molecules in the crystal lattice.

The title compound (Cp*Sn)BPh 4 was obtained by the metathesis reaction of Cp*SnCl with NaBPh 4 and characterized by single crystal X-ray diffraction as well as solution and solid-state 119 Sn nuclear magnetic resonance (NMR) spectroscopy. The coordination modes are best described as ( η 5 -C 5 Me 5 )Sn( μ - η 6 -Ph) 2 BPh 2 .

The fi rst series of building blocks for metal-organic frameworks (MOFs) utilizing the ( S )-2,2 ′ -diethoxy-1,1 ′ binaphthyl-6,6 ′ -dicarboxylic acid ligand linked with a number of α , ω -bis(chlorodiorganostannyl) alkane spacers and α , ω -bis(dichloroorganostannyl) alkane spacers has been synthesized and characterized. The new compounds have been shown to form monomeric chiral rings with the potential to generate large coordination networks. The potential formation of chiral supramolecular and polymeric materials from the chiral precursors was explored by investigating the structures that form as a result of the hypervalency available at metal centers. These chiral compounds were built using the concept that stemmed from the construction of MOFs. The ‘ pre-organized ’ chiral rings synthesized here can potentially fi nd use in chiral catalysis, enantioselective synthesis and in designing chiral polymers.

Chlorotelluration of terminal acetylenes, RCH CH ( R = Ph, 1 ; 4-MeC 6 H 4 , 2 ; t -Bu, 3 ) with aryltellurium trichlorides and TeCl 4 in refluxing toluene affords (2-chloro-2-organylvinyl)tellurium(IV) dichlorides, Ar[R(Cl)C CH]TeCl 2 (Ar = 1-C 10 H 7 , 1Aa – 3Aa ; 2,4,6-Me 3 C 6 H 2 , 1Ba–3Ba ; 4-MeOC 6 H 4 , 1Ca ) and [ t -Bu(Cl)C CH] 2 TeCl 2 , 3a respectively. These Te(IV) derivatives on reduction with Na 2 S 2 O 5 give the corresponding vinyltellurides as oils, except (2,4,6-Me 3 C 6 H 2 )[Ph(Cl)C CH]Te ( 1B ) which is a crystalline solid. The dibromides ( 1Ab – 3Ab , 1Bb – 3Bb , 3b ) and diiodides ( 1Ac – 3Ac , 1Bc – 3Bc , 1Cc ) were obtained by the oxidative addition of dihalogens to the tellurides. The stereochemistry of the products has been established with the help of X-ray diffraction studies of 1Aa , 1Ba , 1Bc , 1Cc , 3Aa , 3a and 1B . Intramolecular Te⋯Cl attractive interactions appear to favor the ( Z ) conformation adopted by the 2-chloro-2-organylvinyltellurium group irrespective of the steric demand of the aryl ligand of the Te(IV) electrophile and the terminal acetylene substituent. The intermolecular Te⋯X secondary bonding interactions give rise to dimeric units in the lattices of 1-naphthyl- and anisyltellurium(IV) derivatives, but are absent among the mesityl analogues, consistent with the larger steric requirement of the latter ligand.

α-Bromo-2-acetylfuran adds oxidatively to elemental tellurium and aryltellurium(II) bromide at ambient temperature to afford (2-furoylmethyl)tellurium(IV) dibromides, (FuCOCH2)2TeBr2 (1b) and Ar(FuCOCH2)TeBr2 (Fu = 2-C4H3O; Ar = 1-C10H7, 2b; 2,4,6-Me3C6H2, 3b). The iodo analogues 1c–3c can be obtained by metathesis of the bromides with an alkali iodide. Condensation reactions of the parent methyl ketone with Te(IV) chlorides results in the corresponding chloro analogues, (FuCOCH2)2TeCl2 (1a) and Ar(FuCOCH2)TeCl2 (2a, 3a and Ar = 4-MeOC6H4 (4a)). These diorganotellurium dihalides are reduced with aqueous bisulfite to diorganotellurides 1–3, which can be oxidized readily with dihalogens to the desired diorganotellurium(IV) dihalides. The tellurated furan derivative, bis(2-furyl)tellurium(II), Fu2Te (5), obtained by detelluration of bis(2-furyl)ditelluride with electrolytic copper, gives crystalline bis(2-furyl)tellurium(IV) dichloride (5a) upon chlorination. Crystal structures of Te(IV) compounds 1a, 1b, 2a–4a, and the telluride 3 together with its thiophene analogue (2,4,6-Me3C6H2)((2-C4H3S)COCH2)Te, 6 have been studied. Among the Te(IV) compounds, the functionalized organic moiety, FuCOCH2-, behaves as a (C, O) chelating ligand, resulting in a intramolecular 1,4-Te⋯O secondary bonding interaction. Such an interaction is absent in Te(II) compounds 3 and 6, though they differ in the conformation adopted by the organic ligand. The chalcogen atoms in the heteroaroyl moiety are trans in 3 but cis in 6 which also possesses intermolecular Te⋯O interaction in its lattice.

Room temperature oxidative addition of α-bromo-2-acetylthiophene to elemental tellurium and aryltellurium(II) bromide provides direct routes to (2-thiophenoylmethyl)tellurium(IV) dibromides, (2-(C4H3S)COCH2)2TeBr2 (1b) and 2-(C4H3S)COCH2ArTeBr2 (Ar = 1-C10H7, Npl, 2b; 2,4,6-Me3C6H2, Mes, 3b). The chloro analogues, 2-(C4H3S)COCH2ArTeCl2 (Ar = Npl, 2a; Mes, 3a) were prepared by the condensation reaction of the parent methyl ketone with NplTeCl3 or MesTeCl3. Metathesis of these products with an alkali iodide affords the iodo analogues 1c, 2c and 3c. These diorganotellurium dihalides are reduced with aqueous bisulfite to diorganotellurides 1–3, which can be oxidized readily with dihalogens to the desired diorganotellurium(IV) dihalides. Compound 1 is a rare example of a symmetrical telluroether with Csp3–Te–Csp3 grouping that has been characterized by single-crystal diffraction techniques. Preference of the 2-thiophenoylmethyl ligand for small-bite (C, O) chelation over less strained (C, S) coordination is evident in the crystal structures of the Te(IV) compounds 1b, 2a, 2b and 3a. The unexpected transoidal orientation of the two acylmethyl ligands in the solid state molecular configuration of symmetrical diorganotellurium(IV) dibromide 1b appears to be a combined effect of electronic repulsion due to the thiophene moieties and steric repulsion of bromo ligands.

Elemental tellurium inserts into the Csp3–Br bond of α-bromomesitylmethyl ketone and due to its strong carbophilic character affords the crystalline C-tellurated derivative of 2,4,6-trimethylacetophenone, (MesCOCH2)2TeBr2, 1b in over 80% yield. Electrophilic substitution of the parent ketone with aryltellurium trichlorides, at room temperature, gives nearly quantitative yields of unsymmetrical alkylaryltellurium dichlorides (MesCOCH2)ArTeCl2 (Ar = mesityl, Mes, 2a; 1-naphthyl, Np, 3a; anisyl, Ans, 4a). Fairly stable mesitoylmethyltellurium(II) derivatives, (MesCOCH2)2Te, 1 and (MesCOCH2)ArTe (Ar = Mes, 2; Np, 3 and Ans, 4) obtained as the reduction products of their dihalotellurium(IV) analogues, readily undergo oxidative addition of dihalogens to afford the corresponding (MesCOCH2)2TeX2 (X = Cl, 1a; Br 1b; I, 1c) and (MesCOCH2)ArTeX2 (X = Cl, Br, I, Ar = Mes, 2a, 2b, 2c; Np, 3a, 3b, 3c and Ans, 4a, 4b, 4c). Crystallographic structural characterization of 1, 1b, 2, 2a, 2b, 2c, 3, 3a and 4c illustrates that the steric demand of mesityl group appreciably influences primary geometry around the 5-coordinate Te(IV) atom when it is bound directly to it. It also makes the Te atom inaccessible for the ubiquitous Te⋯X intermolecular secondary bonding interactions that result in supramolecular structures. In the crystal lattice of symmetrical telluroether 1, an interesting supramolecular synthon based upon reciprocatory weak C–H⋯O H-bonding interaction gives rise to chains via self-assembly.

Enantiomerically pure cis- and trans-myrtanylstannanes cis-MyrSnPh3 (1), trans-MyrSnPh3 (2), cis-MyrSnPh2Cl (3), trans-MyrSnPh2Cl (4), cis-MyrSnPhCl2 (5), trans-MyrSnPhCl2 (6), cis-MyrSnCl3 (7), trans-MyrSnCl3 (8) were synthesized and fully characterized by 1H, 13C and 119Sn NMR spectroscopy. The molecular structures of 1, 3, 6, 7, and [trans-MyrSn(OH)Cl2 · H2O]2 (8a) a hydrolysis product of 8, were determined by X-ray crystallography.

The synthesis and characterization of unsymmetric diorganotellurium compounds containing a sterically demanding 1-naphthyl or mesityl ligand and a small bite chelating organic ligand capable of 1,4-Te⋯N(O) intramolecular interaction is described. The reaction of ArTeCl3 (Ar = 1-C10H7, Np; 2,4,6-Me3C6H2, Mes) with (SB)HgCl [SB = the Schiff base, 2-(4,4′-NO2C6H4CH NC6H3-Me)] or a methyl ketone (RCOCH3) afforded the corresponding dichlorides (SB)ArTeCl2 (Ar = Np, 1Aa; Mes, 1Ba) or (RCOCH2)ArTeCl2 (Ar = Np; R = Ph (2Aa), Me (3Aa), Np (4Aa); Ar = Mes, R = Ph (2Ba)). Reduction of 1Aa and 1Ba by Na2S2O5 readily gave the tellurides (SB)ArTe (Ar = Np (1A), Mes, (1B)) but that of dichlorides derived from methylketones was complicated due to partial decomposition to tellurium powder and diarylditelluride (Ar2Te2), resulting in poor yields of the corresponding tellurides 2A, 2B and 3A. Oxidation of the isolated tellurides with SO2Cl2, Br2 and I2 yielded the corresponding dihalides. All the synthesized compounds have been characterized with the help of IR, 1H, 13C, and 125Te NMR and in the case of 2Aa, and 2Ba by X-ray crystallography. Appearance of only one 125Te signal indicated that the unsymmetric derivatives were stable to disproportionation to symmetric species. Intramolecular 1,4-Te⋯O secondary bonding interactions (SBIs) are exhibited in the crystal structures of both the tellurium(IV) dichlorides, 2Aa, and 2Ba. Steric repulsion of the mesityl group in the latter dominates over lone pair–bond pair repulsion, resulting in significant widening of the equatorial C–Te–C angle. This appears to be responsible for the lack of Te⋯Cl involved supramolecular associations in the crystal structure of 2Ba.

The unsymmetrically substituted diorganotellurium dihalides [2-(4,4′-NO2C6H4CHNC6H3Me]RTeX2 (R = 4-MeOC6H4, X = Cl, 1a; Br, 1b; I, 1c; R = 4-MeC6H4; X = Cl, 2; R = C6H5, X = Cl, 3) were prepared in good yields and characterized by solution and solid-state 125Te NMR spectroscopy, IR spectroscopy and X-ray crystallography. In the solid-state, molecular structures of 1a and 1c possess scarcely observed 1,4-type intramolecular Te⋯N secondary interaction. Crystal packing of these compounds show an unusually rich diversity of intermolecular secondary, Te⋯O, Te⋯I and I⋯I interactions, Te⋯π contacts as well as extensive π-stacking of the organic substituents.

Single crystal X-ray crystallography revealed that the title compound [(4-Me2N)(3-O2N)C6H3]2TeCl2 is associated in the solid state mainly by intermolecular secondary Te‧‧‧O contacts.

The H2PtCl6 catalysed hydrosilylation of the terpenes (+)-α-fenchene (XI), (−)-2-methylene bornane (XII), (+)-camphene (XIII) and (−)-3-methylene fenchane (XIV) using HSiMe2Cl or HSiMeCl2 proceeds with high regioselectively and in some cases, with high diastereoselectivity. KF-assisted oxidation of the hydrosilylation products gives predominately endo-terpene alcohols. The alcohols have inverted endo/exo ratios to those formed by oxidative hydroboration. Reaction of XIV with HSiMe2Cl or HSiMeCl2 is accompanied by a clean rearrangement of the isocamphane skeleton into (+)-2-methylene bornane (XII) prior to hydrosilylation.

By reaction of Zn(CH3COO)2 with p,p′-diphenylmethylenediphosphinic acid in water a new inorganic–organic polymeric hybrid of formula [Zn(CH2(P(Ph)O2)2)] has been synthesized and completely characterized. The X-ray analysis established that the structure consists of 2D-layered polymeric array, the 2D-sheets being built up through strong covalent linkages between the zinc metal and the oxygen donors of the phenylphosphinate ligand. The 2D-layers, which are featuring a mesh-net fashion, present voids of various dimensionality, up to 24-membered rings. The organic parts of the hybrid ligand, namely the phenyl rings, are shielding the inorganic skeleton of the layers, preventing the propagation of the polymer in the third dimension. No water molecules are present in the lattice, both of coordination and crystallization. Crystal data are: monoclinic, P21/c, a=11.840(2), b=9.646(9), c=12.516(5) A, β=95.03(2), V=1423.9(15) A3, Z=4. The solid material has been characterized by 31P MAS NMR spectroscopy and thermogravimetric analysis.

The synthesis of the α,ω-bis[dichloro(trimethylsilylmethyl)stannyl]alkanes, (Me3SiCH2)Cl2Sn(CH2)nSnCl2(CH2SiMe3) (13, n = 5; 14, n = 6; 15, n = 7; 16, n = 8; 17, n = 10; 18, n = 12) and the corresponding oligomethylene-bridged diorganotin oxides [(Me3SiCH2)(O)Sn(CH2)nSn(O)(CH2SiMe3)]m (19, n = 5; 20, n = 6; 21, n = 7; 22, n = 8; 23, n = 10; 24; n = 12) is reported. The reaction of the diorganodichlorostannanes 13–18 with the corresponding diorganotin oxides 19–24 provided the spacer-bridged tetraorganodistannoxanes {[(Me3SiCH2)ClSn(CH2)nSnCl(CH2SiMe3)]O}4 (25, n = 5; 26, n = 6; 27, n = 7; 28, n = 8; 29, n = 10; 30, n = 12). Compounds 13–30 have been identified by elemental analyses and multinuclear NMR spectroscopy. Compounds 25, 27, 29 and 30 have also been characterised by single crystal X-ray diffraction analysis and electrospray mass spectrometry. For the latter the essential double ladder motif is maintained for all n in the solid state, but subtle changes in alignment of the ladder planes occur. Separation between the two layers of the double ladder ranges from approx. 8.7 A (for 25, n = 5) to approx. 15 A (for 30, n = 12). In solution there is some dissociation of the double ladders into the corresponding dimers. The degree of dissociation is favoured by increasing oligomethylene chain length n.

Bis( p -substituted benzoylmethyl)tellurium dibromides, ( p -YC 6 H 4 COCH 2 ) 2 TeBr 2 , (Y=H ( 1a ), Me ( 1b ), MeO ( 1c )) can be prepared either by direct insertion of elemental Te across C Rf –Br bonds (where C Rf refers to α-carbon of a functionalized organic moiety) or by the oxidative addition of bromine to ( p -YC 6 H 4 COCH 2 ) 2 Te (Y=H ( 2a ), Me ( 2b ), MeO ( 2c )). Bis( p -substituted benzoylmethyl)tellurium dichlorides, ( p -YC 6 H 4 COCH 2 ) 2 TeCl 2 (Y=H ( 3a ), Me ( 3b ), MeO ( 3c )), are prepared by the reaction of the bis( p -substituted benzoylmethyl)tellurides 2a – c with SO 2 Cl 2 , whereas the corresponding diiodides ( p -YC 6 H 4 COCH 2 ) 2 TeI 2 (Y=H ( 4a ), Me ( 4b ), MeO ( 4c )) can be obtained by the metathetical reaction of 1a – c with KI, or alternatively, by the oxidative addition of iodine to 2a – c . The reaction of 2a – c with allyl bromide affords the diorganotellurium dibromides 1a – c , rather than the expected triorganotelluronium bromides. Compounds 1 – 4 were characterized by elemental analyses, IR spectroscopy, 1 H, 13 C and 125 Te NMR spectroscopy (solution and solid-state) and in case of 1c also by X-ray crystallography. ( p -MeOC 6 H 4 COCH 2 ) 2 TeBr 2 ( 1c ) provides, a rare example, among organotellurium compounds, of a supramolecular architecture, where C–H–O hydrogen bonds appear to be the non-covalent intermolecular associative force that dominates the crystal packing.

The synthesis of the first example of an organotin double ladder ( 6 ) containing a functional group within the spacer is reported. In the solid state, compound 6 shows an interlaminar cavity whose size and shape suggest the possibility of host–guest chemistry. 119 Sn-NMR and ESMS show that compound 6 undergoes extensive dissociation in solution. ESMS of compound 6 to which have been added Li + , Na + , Mg 2+ or Cu 2+ show only minimal interaction.

The solid-state structures of the previously known para-substituted diphenyltellurium dichlorides, (p-XC6H4)2TeCl2 (X=H (1), Me (2), MeO (3)) were investigated by 125Te MAS NMR spectroscopy and in case of 2 by single crystal X-ray diffraction. The 125Te-NMR shielding anisotropy (SA) was studied by tensor analyses based on relative intensities of the observed spinning sidebands. Solid-state NMR parameters, namely the isotropic chemical shift (δiso), anisotropy (ζ) and asymmetry (η), were discussed in relation to the molecular structures established by X-ray crystallography. The asymmetry (η) was found to be particularly sensitive to structural differences stemming mostly from the diverse secondary Te⋯Cl interactions, but no correlation with geometric parameters could be established.

The hydrolysis of (Me3SiCH2)PhSnCl2 (1) was studied under two different reaction conditions (i) by using an excess of aqueous NaOH in toluene at reflux temperature and (ii) by using small amounts of NEt3 and water in CH2Cl2 at room temperature. For (i) the products (Me3SiCH2)Ph2SnOSnPh2(CH2SiMe3) (2) and [(Me3SiCH2Sn)12O14(OH)6](OH)2 (3) were isolated indicating that a phenyl group migration took place. For (ii) the dimeric tetraorganodistannoxane [(Me3SiCH2)Ph(Cl)SnOSn(Cl)Ph(CH2SiMe3)]2 (4) was obtained. In solution, 4 exists as an equilibrium mixture of all five possible isomers 4a–4e; in the solid state two of these isomers 4d and 4e co-crystallized in the same crystal modification. The observation of interconvertible isomers of 4 was attributed to the kinetic lability of the ladder-like Sn4O2Cl4 structural motif. Compounds 1 and 4 were investigated by X-ray crystallography.

The crystal and molecular structure of Gingras' salt [n-Bu4N]+ [Ph3SnF2]− is reported, which reveals a variety of inter- and intramolecular CH⋯F hydrogen bonding interactions. A 119Sn MAS-NMR spectrum was recorded and a tensor analysis has been performed according to the method of Herzfeld and Berger. The results are discussed in terms of the molecular structure and are compared with the parent compound Ph3SnF as well as with Mes3SnF (Mes=mesityl).

The reaction of the intramolecularly coordinated diaryltellurium(IV) oxide (8-Me2NC10H6)2TeO with acetonitrile proceeds with oxygen transfer and gives rise to the formation of the novel zwitterionic diaryltelluronium(IV) acetimidate (8-Me2NC10H6)2TeNC(O)CH3 (1) in 57% yield. Hydrolysis of 1 with hydrochloric acid affords acetamide and the previously known diarylhydroxytelluronium(IV) chloride [(8-Me2NC10H6)2Te(OH)]Cl.

The reaction of diorganotin sulfides, cyclo-(R2SnS)n (R=Me, n-Bu; n=3; R=t-Bu; n=2) with the corresponding diorganotin dichlorides, R2SnCl2, provided the tetraorganodistannathianes, (R2ClSn)2S (1, R=Me; 2, R=n-Bu; 3, R=t-Bu). 1H-, 13C-, and 119Sn-NMR studies indicate that these compounds are kinetically labile and in equilibrium with the starting materials. Addition of equimolar amounts of [(Ph3P)2N]Cl to the reaction mixtures gave the chloride complexes [(Ph3P)2N]+[S(SnR2Cl)2Cl]− (4, R=Me; 5, R=n-Bu; 6, R=t-Bu). Single-crystal X-ray diffraction studies revealed the tin atoms in both 4 and 6 to adopt distorted trigonal bipyramidal configurations with the chlorine atoms occupying the axial positions.

The complexes [Hpy][Cu(H3L)(H2O)] 1 (L6− = nitrilotrimethylenetrisphosphonate) and [Cu(HL°)(py)]2·2Me2CO 2 [(L°)3− = P,P′,P″-triphenylnitrilotrismethylenetrisphosphinate)] have been isolated and characterized by X-ray crystallography, near IR-visible spectroscopy and magnetic measurements. The structure determination has shown the complexes to be constituted by monomeric and dimeric units respectively. In the monomer the metal atom is surrounded by the phosphonate ligand and a water molecule, with a geometry between a trigonal bipyramid and a square pyramid. The two copper atoms in the dimer are held together by an arm of the tripod ligand, with a pyridine molecule as additional ligand, and display octahedral geometry. The presence of monomeric and dimeric species in aqueous solutions of 1 and 2 has been shown by ESMS studies. The formation in water solution of the dimer [{Cu(H3L)}2]2−, as a minor species, has been supported by potentiometric measurements, whereas only the monomeric anion [CuL°]− has been ascertained to be present. In general the ligand H3L° forms less stable copper(II) complexes than H6L. p

The reaction of α , ω -bis(organodichlorostannyl)alkanes [R(Cl 2 )SnCH 2 ] 2 Z with their corresponding organotin oxides [R(O)SnCH 2 ] 2 Z or ( t -Bu 2 SnO) 3 provides the new spacer-bridged tetraorganodistannoxanes {[R(Cl)SnCH 2 ] 2 Z]O} n ( 22 , Z=CH 2 , R=Me 3 SiCH 2 ; 23 , Z=CH 2 , R=Me 3 CCH 2 ; 24 , Z=CH 2 CH 2 , R=Me 3 SiCH 2 ; 25 , Z=CH 2 CH 2 , R=Me 3 CCH 2 ; 26 , Z=CH 2 CH 2 , R=Me 2 CHCH 2 ; 27 , Z=Me 2 Si, R=Me 3 SiCH 2 ). The acetate substituted derivative 28 {[R(AcO)SnCH 2 ] 2 CH 2 ]O} n (R=Me 3 SiCH 2 ) is obtained by reaction of 22 with silver acetate or by treatment of the organotin oxide [R(O)SnCH 2 ] 2 CH 2 (R=Me 3 SiCH 2 ) with acetic acid. The crystal structures of 23 , 24 , and 28 are described and reveal that these compounds adopt double ladder structures. Depending on the identity of Z and R in chloroform solution the compounds are either dimers ( n =2, 25 – 28 ) or tetramers ( n =4, 22 – 24 ). Also reported are preliminary studies on the catalytic activity in acylation reactions of compounds 22 , 24 – 26 , and 28 .

The Ni atom in the linear polymeric title complex, {[Ni(C 11 H 17 OS 2 ) 2 (C 10 H 8 N 2 )]·2CHC1 3 } n or {Ni[S 2 C(-)-OC 10 H 17 )] 2 (NC 5 H 4 C 5 H 4 N)·2CHC1 3 } n , is octahedrally coordinated within a trans- N 2 S 4 donor set. There are two crystallographically independent polymers and two independent CHC1 3 molecules in the structure. For each polymer unit, the Ni atom and the axis of the 4,4'-bipyridine ligand are located on a twofold axis.

Reported here are the syntheses and molecular structures of three novel arylindium phosphinates, [(2,6- Mes2 C6 H3 In)2(OH)2(O2 PMe2)2] (1), [(2,6-Mes2 C6 H3 In)2(OH)(O2 PPh2)3] (2), and [(2,6-Mes2 C6 H3 In)(O2 PMe5 C3 H)2(H2 O)2] (3), which were obtained by condensation reaction of the m-terphenylindium dihydroxide [(2,6-Mes2 C6 H3 In(OH)2]4 with dimethylphosphinic acid, diphenylphosphinic acid, and 2,2,3,4,4-pentamethylphosphetanic acid, respectively.

The stoichiometrically controlled halogenation of the intramolecularly coordinated diaryltelluride (8-Me2NC10H6)2Te using SO2Cl2, Br2 and I2 was studied. At an equimolar ratio, the diarylhalotelluronium cations [(8-Me2NC10H6)2TeX](+) (1, X = Cl; 2, X = Br; 3, X = I) formed and were isolated as 1·Cl(-)·H2O·1/2THF, 2·Br(-), and 3·I(-), respectively. When the same reactions were carried out in the presence of KPF6, 1·PF6(-) and 22·Br(-)·PF6(-) were obtained. The chlorination of (8-Me2NC10H6)2Te with an excess of SO2Cl2 occurred with a double electrophilic substitution at the 8-dimethylaminonaphthyl residues (in the ortho- and para-positions) and afforded the diaryltellurium dichloride (5,7-Cl2-8-Me2NC10H4)2TeCl2 (4). The bromination of (8-Me2NC10H6)2Te with three equivalents of Br2 took place with a single electrophilic substitution at the 8-dimethylaminonaphthyl residues (in the para-positions) and provided the diaryltellurium dibromide (5-Br-8-Me2NC10H5)2TeBr2 (5), while an excess of Br2 produced the diarylbromotelluronium cation [(5-Br-8-Me2NC10H5)2TeBr](+) (6) that was isolated as 6·Br3(-). The reaction of (8-Me2NC10H6)2Te with two or three equivalents of iodine provided 3·I3(-) and 3·I3(-)·I2, respectively. In the presence of water, 1·Cl(-)·H2O·1/2THF, 2·Br(-), 3·I(-) and 3·I3(-) hydrolyzed to give the previously known diarylhydroxytelluronium cation [(8-Me2NC10H6)2TeOH](+) (7) that was isolated as 7·Cl(-), 7·Br(-)·H2O·THF, 7·I(-) and 7·I3(-)·H2O, respectively. The molecular structures of 1-7 were investigated in the solid-state by (125)Te MAS NMR spectroscopy and X-ray crystallography and in solution by multinuclear NMR spectroscopy ((1)H, (13)C, (125)Te), electrospray mass spectrometry and conductivity measurements. The stabilization of cations 1-3 by the intramolecular coordination was estimated by DFT calculations at the B3PW91/TZ level of theory.

Five new organotin(IV) complexes of composition [Bz2SnL1]n (), [Bz3SnL1H⋅H2O] (), [Me2SnL2⋅H2O] (), [Me2SnL3] () and [Bz3SnL3H]n () (where L1 = (2S)-2-{[(E)-(4-hydroxypentan-2-ylidene)]amino}-4-methylpentanoate, L2 = (rac)-2-{[(E)-1-(2-hydroxyphenyl)methylidene]amino}-4-methylpentanoate and L3 = (2S)- or (rac)-2-{[(E)-1-(2-hydroxyphenyl)ethylidene]amino}-4-methylpentanoate) were synthesized and characterized using 1H NMR, 13C NMR, 119Sn NMR and infrared spectroscopic techniques. The crystal structure of reveals a distorted trigonal-bipyramidal geometry around the tin atom where the oxygen atoms of the carboxylate ligand and a water ligand occupy the axial positions, while the three benzyl ligands are located at the equatorial positions. On the other hand, the analogous derivative of enantiopure L3H () consists of polymeric chains, in which the ligand-bridged tin atoms adopt the same trans-Bz3SnO2 trigonal-bipyramidal configuration and are now coordinated to a phenolic oxygen atom instead of H2O. In , the OH hydrogen of the ketoimine substituent has moved to the nearby nitrogen atom while in the salicylidene derivative , the OH is located almost midway between the phenolic oxygen atom and the nitrogen atom of the C[DOUBLE BOND]N group. For the dibenzyltin derivative , a polymeric chain structure is observed as a result of a long intermolecular Sn⋅⋅⋅O bond involving the exocyclic carbonyl oxygen atom from the tridentate ligand of a neighbouring tin-complex unit. The tin atom in this complex has distorted octahedral coordination geometry. In contrast, the racemic dimethyltin(IV) complexes and display discrete monomeric structures with a distorted octahedral- and trigonal-bipyramidal geometry, respectively. The structures show that the coordination mode of the Schiff base ligand depends primarily on the number of bulky benzyl ligands (R) at the tin atom, as indeed found in the structures of related complexes where R = phenyl. With three bulky R groups, the tridentate chelating O,N,O coordination mode is preferred, whereas with fewer or less bulky R ligands, only the carboxylate and hydroxy groups are involved, which leads to polymers. Larvicidal efficacies of two of the new tribenzyltin(IV) complexes ( and ) were assessed on the second larval instar of Anopheles stephensi mosquito larvae and compared with two triphenyltin(IV) analogues, [Ph3SnL1H]n and [Ph3SnL3H]n. The results demonstrate that the compounds containing Sn–Ph ligands are more effective than those with Sn–Bz ligands. Copyright © 2016 John Wiley & Sons, Ltd.

A strategy for the preparation of the otherwise difficult to obtain binary organometallic oxides containing two heavy main group elements is described and exemplified by the synthesis of [(p-MeOC6H4)2Te(OSnt-Bu2OH)2]2.

Preliminary results are described on the synthesis and characterization of novel spacer-bridged tetraorganodistannoxanes, {[[R(Cl)Sn] 2 (CH 2 ) 2 ]O} 4 (n = 5 – 8, 10, 12; R = CH 2 SiMe 3 ) containing particularly long organic spacers. In the solid state, these compounds reveal typical double-ladder structures with eight tin atoms per molecule, whereas in solution a partial and reversible rearrangement takes place to form tetraorganodistannoxanes, {[[R(Cl)Sn] 2 (CH 2 ) n ]O} 2 (n = 5 – 8, 10, 12; R = CH 2 SiMe 3 ), having four tin atoms per molecule.

CI2H8BrN, monoclinic, Pl21/cl (No. 14), a = 7.555(6) A, b =7.727(3) A, c =16.643(2) A, β =98.95(2)°, V =959.8 A3 , Z =4, Rgt(F) =0.033, wRref(F2) =0.097, T =173 K.

The title compound, C12H24O2 2+·2CF3O3S−, is the first bisoxonium salt for which a crystal structure is reported. The cation is located on an inversion centre and it features a nonplanar C3O+ oxonium unit where the O atom is displaced by 0.375 (2) Å from the plane of its substituents.

In the crystal structure of the title compound, C10H10N3+·Cl-·[P(O)(OH)2H], the chloride ion and phosphorous acid form a one-dimensional hydrogen-bonded chain, while the 2-(2-pyridylamino)pyridinium cations form a second chain through [π]-[π] stacking. The two parallel chains are connected via a PO...H-N hydrogen bond and a weak pyridinium-to-chloride interaction.

Unlike the previously known monoclinic form, the ortho­rhombic polymorph of di­chloro­bis­[4-(di­methyl­amino)­phenyl]­tellurium, C16H20Cl2N2Te, shows secondary Te⋯Cl interactions.

The previously described structure of di­phenyl­tellurium dibromide, C12H10Br2Te, has been reinvestigated. The molecule lies on a twofold rotation axis.

The title compound, [Sn 2 Te 2 (C 4 H 9 ) 4 (CO 3 ) 2 O 2 (C 8 H 10 N) 4 ]·4CHCl 3 or [( p -Me 2 NC 6 H 4 ) 2 TeOSn t Bu 2 CO 3 ] 2 ·4CHCl 3 , contains an almost planar centrosymmetric inorganic Sn 2 Te 2 O 8 C 2 core and hypercoordinated Sn and Te atoms. The structure features four secondary intramolecular Te...O contacts.