32294-58-9Relevant articles and documents
Synthesis, characterization, and ligand behaviour of a new ditelluroether (C10H7)Te(CH2)4Te(C10H7) and the concurrently formed ionic [(C10H7)Te(CH2)4]Br
Poropudas, Merja J.,Rautiainen, J. Mikko,Oilunkaniemi, Raija,Laitinen, Risto S.
, p. 17206 - 17215 (2016)
The reaction of 1-naphthyl bromide with n-butyl lithium, elemental tellurium, and 1,4-dibromobutane in THF affords both (C10H7)Te(CH2)4Te(C10H7) (1) and [(C10H7)Te(CH2)4]Br (2) in good yields. 1 is preferentially formed at low temperatures and is a rare example of a structurally characterized ditelluroether in which the tellurium atoms are bridged by a hydrocarbon chain. In the solid state, 1 shows secondary bonding Te?Te interactions, which connect the molecules into layers which are further linked to 3-dimensional frameworks by Te?H hydrogen bonds. [(C10H7)Te(CH2)4]Br (2) is formed concurrently during the synthesis of 1 and is the main product, when the reaction is carried out at room temperature. The revPBE/def2-TZVPP calculations of the reaction profiles indicate that the formation of 2 is somewhat more favourable than that of 1. Furthermore, at room temperature the activation energy for the formation of 2 is lower than that of 1. At low temperatures the activation energy of the reaction leading to 1 is lower than that to 2, which is consistent with the synthetic observations. When 1 was treated with CuBr, [Cu2(μ-Br)2{μ-(C10H7)Te(CH2)4Te(C10H7)}2] (3) was formed. It crystallizes as two polymorphs (3a) and (3b) in which both the packing and the conformation of the ditelluroether ligands are different. The reaction of 1 with HgCl2 produces [(C10H7)Te(CH2)4]2[HgCl4]·CH2Cl2 (4·CH2Cl2) and that of 1 with CuCl2 affords [(C10H7)Te(CH2)4]Cl (5). 2 and 5 are isomorphous.
Synthesis and characterization of some α-naphthyl selenium/tellurium derivatives: X-ray crystal structure of benzyl-1-naphthyl selenide and diphenylmethyl-1-naphthyl selenide
Bhasin,Singh, Neelam,Dhiman, Rishu,Ram, Ganga,Shivani,Mehta,Butcher
, p. 621 - 628 (2006)
A large number of α-naphthyl selenium and tellurium compounds (1-14) have been prepared through two different methods. The first method involves the alkylation of sodium 1-naphthylselenolate/tellurolate, generated in situ using hydrazine hydrate as reduci
Bis(1-naphthyl) ditelluride
Lang, Ernesto Schulz,Burrow, Robert Alan,Silveira, Edson Tarabal
, p. o397-o398 (2002)
The title compound, C20H14Te2, shows a transoid conformation, with a C-Te-Te-C torsion angle of 97.96 (9). The Te-Te units show approximate η6 interactions with neighbouring naphthyl groups, forming chains along the c axis. The molecule lies about a crystallographic twofold axis.
Reactivity of Selenocystine and Tellurocystine: Structure and Antioxidant Activity of the Derivatives
Satheeshkumar, Kandhan,Raju, Saravanan,Singh, Harkesh B.,Butcher, Ray J.
supporting information, p. 17513 - 17522 (2018/11/23)
l-Selenocystine (5) and l-tellurocystine (6) have been prepared and the reactivity of these amino acids, i.e., oxidation of 5 and 6, has been performed at various pH values. Hydrogen peroxide was used as an oxidant and it was treated with 5 and 6 in excess in acidic and basic media. Compound 5, upon oxidation, afforded SeIV and SeVI products. Selenocysteic acid [HO3SeCH2CH(NH2)COOH] 9, a novel SeVI compound, was isolated and characterised by single-crystal X-ray diffraction studies. In contrast, l-tellurocystine, upon oxidation with H2O2, afforded TeII and TeIV products. Zwitterionic organotellurolate(IV), [TeCl3CH2CH(NH3)COOH] 13, was isolated and characterised by NMR and IR spectroscopy, mass spectrometry and elemental analysis. Compound 13 crystallizes in an orthorhombic space group. l-Tellurocystine, when reduced with NaBH4, produced the desired tellurolate intermediate, which was trapped with bromoacetic acid. Furthermore, l- and d-tellurocysteine derivatives, [(RTeCH2CH(NH2)COOH) R=phenyl, substituted phenyl and naphthyl (24–39)] were synthesised and evaluated for their glutathione peroxidase (GPx)-like activities. The results show that l-tellurocysteine derivatives have higher activity than their D-tellurocysteine analogues. DFT calculations for l-tellurocysteine derivatives provided information about the bond lengths and bond angles. This study reveals that the introduction of naphthyl substituents (35–38) leads to twisted conformation of the amino acid derivatives.
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.
α-Telluration of 2,4,6-trimethylacetophenone under mild conditions: Role of steric factor in the solid state structures of Te(II and IV) compounds
Chauhan, Ashok K.S.,Singh, Puspendra,Srivastava, Ramesh C.,Butcher, Ray J.,Duthie, Andrew
body text, p. 2118 - 2125 (2010/09/20)
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 (MesCOCH 2)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. α-Bromo-2,4,6-trimethylacetophenone adds oxidatively to Te0/TeII to give the dialkyl- or alkylarylTeIV species which on reduction afford carbonyl-functionalized telluroethers.
Ultrasound-assisted synthesis of symmetrical biaryls by palladium-catalyzed detelluration of 1,2-diarylditellanes
Singh, Fateh V.,Stefani, Hélio A.
experimental part, p. 863 - 867 (2010/03/24)
An ultrasound-assisted synthesis of functionalized symmetrical biaryls with electron-withdrawing or electron-donating substituents is described and illustrated by the palladium-catalyzed detelluration of 1,2-diarylditellanes. This procedure offers easy access to symmetrical biaryls in short reaction time and the products are achieved in good to excellent yields.
Sunlight oxidation of alkyl aryl tellurides to the corresponding carbonyl compounds: A new carbonyl precursor
Ouchi, Akihiko,Hyugano, Takeshi,Liu, Chuanxiang
supporting information; experimental part, p. 4870 - 4873 (2010/01/06)
Alkyl aryl tellurides were efficiently transformed to the corresponding carbonyl compounds by photo-oxidation with sunlight without affecting various functional groups in the alkyl moiety. The tellurides can be used as a new carbonyl precursor, and the photolysis can be conducted without special equipment for light sources.
1-Naphthyl- and mesityltellurium(IV, II) derivatives of small bite chelating organic ligands: Effect of steric bulk and intramolecular secondary bonding interaction on molecular geometry and supramolecular association
Chauhan, Ashok K.S.,Anamika,Kumar, Arun,Srivastava, Ramesh C.,Butcher,Duthie, Andrew
, p. 5899 - 5906 (2007/10/03)
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{double bond, long}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.
