92720-46-2Relevant academic research and scientific papers
Syntheses and Structures of Zinc(tmeda)bis(aryltellurolato) and its Facile Chalcogenospecific Ligand Exchange Reactivity
Behr, Sandra,Bestvater, Thorsten,Feldmann, Arnold,Kirschbaum, Kristin,Conrad, Olaf,Giolando, Dean M.
, p. 1431 - 1438 (2018/09/25)
Anaerobic treatment of Zn(tmeda)Br2, where tmeda denotes N,N,N′,N′-tetramethylethylenediamine, with a solution of Na(TeAr), sodium aryltellurolate, in ethanol in a 1:2 stoichiometry led to the formation of highly air sensitive Zn(tmeda)(TeAr)2 (1–3), while a 1:1 stoichiometry afforded Zn(tmeda)Br(TeAr) (4). Crystallography revealed all complexes to be monomeric with four coordinate central zinc atoms bound to tmeda and two TeAr, or a TeAr and a Br ligand. Upon mixing two symmetrically substituted Zn(tmeda)(TeAr)2 complexes in solution, 125Te NMR revealed a facile ligand exchange providing Zn(tmeda)(TeAr)(TeAr′). In addition, Zn(tmeda)(TeAr)(TeAr′) complexes form on mixing symmetric Zn(tmeda)(TeAr)2 complexes and (TeAr′)2. The lability of the zinc complexes was put to advantage in ligand-substitution reactions wherein treatment of SnCl4 with Zn(tmeda)(TeAr)2 affords Sn(TeAr)4 in excellent yields without the concurrent formation of the redox product (TeAr)2. The apparent lability of the Zn–Te bond prevented the volatilization of 1–3 for their use as chemical vapor deposition precursors for the fabrication of ZnTe thin films. On heating, to volatize the complexes, the complexes decompose to cubic ZnTe and TeAr2 sublimes from the samples. Thermal gravimetric analysis indicates the loss of tmeda followed by the loss of TeAr2.
Synthesis and characterization of selenium(I/II) and tellurium(IV) derivatives of amino acids
Singh, Puspendra,Singh, Harkesh B.,Butcher, Ray J.
supporting information, p. 1 - 9 (2018/09/21)
The direct reaction between Te metal and methyl 2-(2-bromoacetamido)propanoate (27) at room temperature, yields the first example of organotellurium(IV) derivative (MeOC(O)CH(Me)NHCOCH2)2TeBr2 (31). Similarly, reaction of Te with methyl 2-(2-bromoacetamido)acetate (26) and methyl 2-(2-bromoacetamido)-3-phenylpropanoate (28) in presence of NaI in acetone gives MeOC(O)CH2NHCOCH2I (29), MeOC(O)CH(R)NHCOCH2)2TeI2 (R = H (30) and CH2Ph (32). Treatment of 26/27/28 with Li2Te2/Li2Se2 readily provides the [MeOC(O)CH(CH3)NHCOCH2]2Te2, (33); [MeOC(O)CH2NHCOCH2]2Se2, (34); [MeOC(O)CH(CH2Ph)NHCOCH2]2Se2, (35) and [Figure presented] (36). Similarly the reaction of (2,6-dimethyl-4-tert-butylC6H2)SeNa with 28 readily provide the [MeOC(O)CH(CH2Ph)NHCOCH2]SeC6H2-2,6-dimethyl-4-tert-butyl), (37) in good yield. Molecule [MeOC(O)CHNH(Boc)CH2]2Se2, (38) and [NaOC(O)CHNH(Boc)CH2Te(2,4,6-Me3C6H2] (39) were prepared by the treatment of Li2Se2/2,4,6-Me3C6H2TeNa with methyl 3-bromo-2-((tert-butoxycarbonyl)amino)propanoate and N-(t-Boc)-L-serine β-lactone respectively. These compounds are purified by chromatography and characterized by a number of analytical techniques such as (1H, 13C, 77Se and 125Te NMR) spectroscopy, mass spectrometry and elemental analysis. The single crystal X-ray studies of 29, 30, 31, 36 and 38 revealed the presence of characteristic O?Se/Te, secondary bonding interactions. A detailed analysis of the crystal structures of the compound reveals interesting supramolecular assembly.
Piperidin-1-ylamidomethyltellurium derivatives: Synthesis and solid state structures
Khan, Mariya,Misra, Shafalika,Srivastava, Ramesh C.,Chauhan, Ashok K.S.,Duthie, Andrew,Butcher, Ray J.
, p. 209 - 214 (2017/04/06)
Oxidative insertion of low valent tellurium, Te(0) and Te(II), into the C–Br bond of α-bromoacetylpiperidine proceeds readily under mild conditions and provides a direct synthetic route to stable, crystalline piperidin-1-ylamidomethyltellurium(IV) dibromides, (C5H10NCOCH2)2TeBr2, 1b and (C5H10NCOCH2)ArTeBr2 (Ar?=?2,4,6-Me3C6H2, 2b; 1-C10H7, 3b; 4-MeC6H4, 4b). While the bisulfite reduction of 1b affords a yellow coloured telluroether, (C5H10NCOCH2)2Te, 1 as an oil, that of the unsymmetrical diorganotellurium dibromides, (C5H10NCOCH2)ArTeBr2 leads to the isolation of the respective diarylditellurides, ArTeTeAr. The symmetrical telluroether, 1 adds dihalogens oxidatively to give piperidin-1-ylamidomethyltellurium(IV) dihalides, (C5H10NCOCH2)2TeX2 (X?=?Cl, 1a; Br, 1b and I, 1c;). All the new piperidin-1-ylamidomethyltellurium derivatives have been characterized by elemental and 1H, 13C, 125Te NMR spectral analyses. Single-crystal X-ray diffraction data for 1b and 1c indicated a butterfly molecular shape for the two halo analogues in which the six-member heterocyclic rings in the organic ligands retain the chair conformation of the independent piperidine molecule. The piperidin-1-yl appended organic ligand invariably results in the amido O atom being involved in an intramolecular Te O secondary bonding interaction and acts as a small-bite (C, O) chelating agent, at least in the solid state. Steric congestion around the six-coordinate Te(IV) atom and the partial positive charge on N owing to the resonating character of the N[pdbdtd]C[pdbdtd]O amido group prevents these atoms from participating in the intermolecular associative forces. Instead, the weak C–H?O and C–H?Br interactions take centre-stage in the solid state self-assembly.
Platinum-Mediated Activation of Coordinated Organonitriles by Telluroethers in Tetrahydrofuran: Isolation, Structural Characterization, and Density Functional Theory Analysis of Intermediate Complexes
Kolay, Siddhartha,Wadawale, Amey,Nigam, Sandeep,Kumar, Mukesh,Majumder, Chiranjib,Das, Dasarathi,Jain, Vimal K.
supporting information, p. 11741 - 11750 (2015/12/31)
The reactions of [PtCl2(NCR)2] with telluroethers (ArAr′Te) in organic solvents have been investigated. The reactions in dichloromethane yield [PtCl2(TeArAr′)2], while those in tetrahydrofuran (THF) give different products depending on the steric demands of the aryl groups on tellurium, the molarity of the reactants, and the reaction conditions. The reactions between [PtCl2(PhCN)2] and TeArAr′ in 1:1 molar ratio at room temperature in THF yield several products, like [PtCl2(TeArAr′)2] (Ar/Ar′ = Ph/Ph, o-tol/Mes, Mes/Mes), [PtCl2(PhCN){NC(O)Ph[TeMes(o-tol)]}], and [PtCl2{NC(O)Ph(TeMes2)}2]. The reaction with TeMes2 in refluxing THF gave [PtCl2{NC(Ph)C4H7O}{NC(O)Ph(TeMes2)}] and [PtCl(TeMes2){Te(Mes)CH2C6H2Me2}], depending on the duration of heating. Reaction of [PtCl2(PhCN)2] with TeArMes afforded [PtCl2(TeArMes)2] (Ar = Ph, o-tol, and Mes), the formation of which decreased with increasing steric demand of the Ar group, together with [PtCl2{NC(O)Ph(TeArMes)}2]. The telluroether in the latter binds to nitrogen, and tellurium exists in the formal oxidation state of +4 (from XPS). The tellurium in these complexes exhibits secondary interactions with platinum (J(195Pt-125Te) = 309-347 Hz) and with the carbonyl oxygen. These complexes slowly dissociate in solution to give [PtCl2(TeMesAr){NC(O)Ph(TeMesAr)}], finally leading to the formation of [PtCl2(TeMesAr)2]. Molecular structures of trans-[PtCl2(PhCN){NC(O)Ph[TeMes(o-tol)]}], trans-[PtCl2{NC(O)Ph(TeMes2)}2], trans-[PtCl2{NC(Ph)C4H7O}{NC(O)Ph(TeMes2)}], trans-[PtCl2{NC(O)Ph[TeMes(o-tol)]}2], trans-[PtCl2(TeMes2){NC(O)Ph(TeMes2)}], trans-[PtCl2{NC(O)Me(TeMes2)}2], and [PtCl(Te-o-tol){NC(O)Ph}2] have been unambiguously established by single-crystal X-ray diffraction analyses. Density functional theory calculations for some of the complexes were performed, and geometrical parameters are in good agreement with the values obtained from X-ray analyses.
Cyclopalladation of telluro ether ligands: Synthesis, reactivity and structural characterization
Kolay, Siddhartha,Kumar, Mukesh,Wadawale, Amey,Das, Dasarathi,Jain, Vimal K.
supporting information, p. 16056 - 16065 (2015/01/09)
Treatment of [PdCl2(PhCN)2] with diaryl telluride in 1:2 molar ratio gave mononuclear palladium complexes, trans-[PdCl2(TeR2)2] (1) (R = Mes (1a) (Mes = 2,4,6-trimethylphenyl), Ph (1b), o-tol (1c) (o-tol = ortho-tolyl)). Reaction of [PdCl2(TeMes2)2] with one equivalent of [PdCl2(PhCN)2] or Na2PdCl4 with TeRR′ afforded chloro-bridged binuclear complexes, [Pd2(μ-Cl)2Cl2(TeRR′)2] (2) (R/R′ = Mes/Mes (2a); Mes/Ph (2b); Ph/Ph (2c)). A toluene-methanol solution of trans-[PdCl2(TeMes2)2] on refluxing for 30 minutes yielded a binuclear cyclopalladated complex, [Pd2(μ-Cl)2{CH2C6H2(4,6-Me2)TeMes)}2] (3). When the refluxing was prolonged, a mononuclear complex cis-[PdCl2{MesTeCH2C6H2(4,6-Me2)TeMes}] (4) was isolated. Treatment of palladium acetate with TeMes2 afforded an acetato-bridged analogue of 3, [Pd2(μ-OAc)2{CH2C6H2(4,6-Me2)TeMes}2] (5a) together with a very minor component, a tetranuclear complex, [Pd(μ-OAc)(μ-TeMes)]4 (6). This reaction with unsymmetrical tellurides, MesTeR, also gave cyclopalladated complexes [Pd2(μ-OAc)2{CH2C6H2(4,6-Me2)TeR}2] (R = o-tol (5b) and Ph (5c)) in which 2-methyl of the mesityl group of the telluride was exclusively metallated. The complex trans-[PdCl2(TeMes2)2] on refluxing in xylene gave palladium telluride, Pd7Te3. These complexes were characterized by elemental analyses, IR and NMR (1H, 13C and 125Te) spectroscopy. The molecular structures of trans-[PdCl2(TeMes2)2] (1a), [Pd2(μ-Cl)2Cl2(TeMes2)2]·2acetone (2a·2acetone), cis-[PdCl2{MesTeCH2C6H2(4,6-Me2)TeMes}] (4), [Pd2(μ-OAc)2{CH2C6H2(4,6-Me2)TeMes)}2]·toluene (5a·toluene), [Pd2(μ-OAc)2{CH2C6H2(4,6-Me2)Tetol-o}2] (5b) and [Pd(μ-OAc)(μ-TeMes)]4 (6) were established by single crystal X-ray diffraction analyses. The mononuclear complex 1a was isolated in two polymorphic forms each with the trans configuration. This journal is
Aerobic photooxidation of phosphite esters using diorganotelluride catalysts
Oba, Makoto,Okada, Yasunori,Nishiyama, Kozaburo,Ando, Wataru
supporting information; experimental part, p. 1879 - 1881 (2009/10/10)
Diorganotellurides containing bulky aromatic substituents are found to catalyze the photooxidation of phosphite esters using aerobic oxygen as a terminal oxidant. A Hammett plot with substituted triaryl phosphites yielding p = 2.88 agrees with a nucleophilic oxygen transfer from telluroxide to phosphite.2009 American Chemical Society.
Sodium telluride in N-methyl-2-pyrrolidone: An efficient telluration system for the synthesis of aromatic tellurides and ditellurides
Suzuki,Nakamura
, p. 549 - 551 (2007/10/02)
Sodium telluride prepared in situ from tellurium and sodium hydride in N-methyl-2-pyrrolidone was found to act as an efficient tellurating agent for nonactivated aromatic iodides, providing a simple route to a variety of diaryl tellurides, alkyl aryl tellurides and diaryl ditellurides.
Sterically Hindered Thiolato, Selenolato and Tellurolato Complexes of Mercury(II)
Bochmann, Manfred,Webb, Kevin J.
, p. 2325 - 2330 (2007/10/02)
Mercury(II) complexes of sterically demanding arenechalcogenolato ligands, Hg(EC6H2-2,4,6)2 (E = S or Se; R = Me, Pri or But: E = Te; R = Me or Pri) have been prepared.Whereas complexes carrying smaller aryl substituents (R = Me) are polymeric, those with R = Pri and But form linear two-co-ordinate molecules.For a given R, the volatility of the complexes increases for E = S Pri >> But.
Organotellurium Chemistry. 9. Structural Parameters in the Telluroxide-Catalyzed Aldol Condensation
Akiba, Mitsuo,Lakshmikantham, M. V.,Jen, Kwan-Yue,Cava, Michael P.
, p. 4819 - 4821 (2007/10/02)
A number of aromatic telluroxides have been prepared and their reactivity as aldol catalysts has been determined.High catalytic activity is associated with electron-donating substituents on the aromatic ring which can increase the basicity of the telluroxide function by a resonance effect.
