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Tiekink, Edward R. T. - One of the best experts on this subject based on the ideXlab platform.
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Bis[(4-methylphenyl)ethynyl] telluride
Wiley-Blackwell, 2010Co-Authors: Caracelli Ignez, Zukerman-schpector Julio, Pena, Jesus M., Stefani, Helio A., Tiekink, Edward R. T.Abstract:The Tellurium Atom in the title bis-ethynyl telluride, Te(C(9)H(7))(2) or C(18)H(14)Te, is located on a crystallographic twofold axis, the C-Te-C angle being 92.23 (15)degrees. The dihedral angle between the rings is 87.27 (7)degrees. In the crystal structure, molecules are connected in chains parallel to the b axis and mediated by C-H center dot center dot center dot pi interactions.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
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Bis[(4-methylphenyl)ethynyl] telluride
WILEY-BLACKWELL, 2010Co-Authors: Caracelli Ignez, Zukerman-schpector Julio, Pena, Jesus M., Stefani, Helio A., Tiekink, Edward R. T.Abstract:The Tellurium Atom in the title bis-ethynyl telluride, Te(C(9)H(7))(2) or C(18)H(14)Te, is located on a crystallographic twofold axis, the C-Te-C angle being 92.23 (15)degrees. The dihedral angle between the rings is 87.27 (7)degrees. In the crystal structure, molecules are connected in chains parallel to the b axis and mediated by C-H center dot center dot center dot pi interactions
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Bis[(4-methylphenyl)ethynyl] telluride
WILEY-BLACKWELL, 2010Co-Authors: Caracelli Ignez, Zukerman-schpector Julio, Pena, Jesus M., Stefani, Helio A., Tiekink, Edward R. T.Abstract:The Tellurium Atom in the title bis-ethynyl telluride, Te(C(9)H(7))(2) or C(18)H(14)Te, is located on a crystallographic twofold axis, the C-Te-C angle being 92.23 (15)degrees. The dihedral angle between the rings is 87.27 (7)degrees. In the crystal structure, molecules are connected in chains parallel to the b axis and mediated by C-H center dot center dot center dot pi interactions.FAPESP[07/59404-2]CNPq[472237/2008-0]CNPq[300613/2007]CNPq[306532/2009-3]CAPES[808/2009
Rj Butcher - One of the best experts on this subject based on the ideXlab platform.
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Facile Cleavage of Organochalcogen Hybrid (NEEN, NEN, EN, where E = Se or Te) Ligand C-E and E-E Bonds by Pd(II)
'American Chemical Society (ACS)', 2009Co-Authors: Kaur R, Hb Singh, Sc Menon, Panda S, Rp Patel, Rj ButcherAbstract:The synthesis and characterization of chiral hybrid ligand R(2)*Se(2) (R* = 2-Me(2)NCH(Me)C(6)H(4)) (9) and some of its derivatives is described. The reaction of 9 with a Pd(II) chloride complex leads to cleavage of the Se-Se bond and formation of the corresponding areneselenenyl chloride, R*SeCl (18). However, reactions of [RS;RS] and [SR; SR] bis[2-{1-(dimethylamine)ethyl}ferrocenyl] diselenides (7 and 8) with a Pd(II) chloride complex under identical conditions afford dinuclear complexes [PdCl{(SeC(5)H(3)CH(Me)NMe(2)-2)Fe(C(5)H(5))}](2) (19 and 20). Reaction of achiral ditelluride, R(2)Te(2) (R = 2-Me(2)NCH(2)C(6)H(4)) (10), with a Pd(II) chloride complex gives a novel dinuclear complex, [PdCl(TeC(6)H(4)CH(2)NMe(2)-2)](2) (21), and the dimeric Tellurium complex (RTeCl)(2) (22), whereas the reaction of chiral Schiff base tridentate Tellurium ligand R'(2)Te (R' = 2-C(6)H(4)CH=NCH(Me)C(6)H(5)) (11) with a Pd(II) chloride complex produces cleaved products (R'PdCl)(2) (23) and (R'TeCl)(2) (24). Similarly, the reaction between the tridentate ligand R(2)Te (12) and Pd(COD)Cl(2) gives 22 and the dimeric palladium complex (RPdCl)(2) (25). The treatment of bidentate ligand RTeMe (13) results in decomposition of the ligand and precipitation of Te. All the compounds are characterized by detailed IR and NMR ((1)H, (13)C, (77)Se, and (125)Te) spectroscopic techniques, MS, and optical rotation measurements. The structures of R*SeBr (17), 21, 24, and 25 were determined by single-crystal X-ray crystallography. In 17 the coordination geometry around selenium is essentially T-shaped with a short Se center dot center dot center dot N distance (2.132(6) angstrom). The palladium tellurolato complex 21 crystallizes as a centrosymmetric dimer. Compound 23 crystallizes as a dimer in which each Tellurium Atom coordinates to two bridging chlorines, one nitrogen, and one carbon. Compound 25 crystallizes as a chloro-bridged centrosymmetric dimer
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O-hydroxylmethylphenylchalcogens: synthesis, intramolecular nonbonded chalcogen center dot center dot center dot oh interactions, and glutathione peroxidase-like activity
'American Chemical Society (ACS)', 2005Co-Authors: Sk Tripathi, Hb Singh, Patel U, Roy D, Rb Sunoj, Wolmershauser G, Rj ButcherAbstract:The synthesis and characterization of a series of organochalcogen (Se, Te) compounds derived from benzyl alcohol 13 are described. The synthesis of the key precursor dichalcogenides 15, 22, and 29 was achieved by the ortho-lithiation route. Selenide 18 was obtained by the reaction of the dilithiated derivative 14 with Se(dtc)(2). Oxidation of 15 and 22 with H2O2 afforded the corresponding cyclic ester derivatives 17 and 24, respectively. Oxidation of selenide 18 with H2O2 affords the spirocyclic compound 19. The presence of intramolecular interactions in dichalcogenides 15 and 22 has been proven by single-crystal X-ray studies. The cyclic compounds 17 and 19 have also been characterized by single-crystal X-ray studies. GP(X)-like antioxidant activity of selenium compounds has been evaluated by the coupled bioassay method. Density functional theory calculations at the mPW1PW91 level on ditelluride 22 have identified a fairly strong nonbonding interaction between the hydroxy oxygen and Tellurium Atom. The second-order perturbation energy obtained through NBO analysis conveys the involvement of n(O) -> sigma*(Te-Te) orbital overlap in nonbonding interaction. Post wave function analysis with the Atoms in Molecules (AIM) method identified distinct bond critical point in 15 and 22 and also indicated that the nonbonding interaction is predominantly covalent. Comparison between diselenide 15 and ditelluride 22 using the extent of orbital interaction as well as the value of electron density at the bond critical points unequivocally established that a ditelluride could be a better acceptor in nonbonding interaction, when the hydroxy group acts as the donor
Butcher, Ray J. - One of the best experts on this subject based on the ideXlab platform.
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Isolation of the novel example of a monomeric organotellurinic acid
'Royal Society of Chemistry (RSC)', 2020Co-Authors: Deka Rajesh, Sarkar Arup, Butcher, Ray J., Junk, Peter C., Turner, David R., Deacon, Glen B., Singh, Harkesh B.Abstract:The stoichiometrically controlled alkaline hydrolysis of 4, (ppy)TeCl3, [ppy = 2-(2'-pyridyl)phenyl] afforded the partially hydrolyzed mu-oxo-bridged dinuclear telluroxane 5, [(ppyTeCl(2))(2)(mu-O)] and a novel example of an Intramolecular Chalcogen Bonding (IChB) stabilized, monomeric organotellurinic acid 6, (ppy)Te(O)OH. The oxidation of diaryl ditelluride 7, (ppyTe)(2) using H2O2 resulted in the isolation of mu-oxo-bridged dimethyl ester 8, [(ppy)Te(O)(OH)(OMe)](2)(O). The molecular structures of 4-6 and 8 are unambiguously authenticated by single crystal X-ray diffraction studies. The electronic structure of monomeric tellurinic acid 6 is investigated using DFT calculations. The Natural Bond Order (NBO) analysis, in corroboration with Atoms in Molecules (AIM) analysis reveals that tellurinic acid 6 is stabilized by sigma-hole participation of the Tellurium Atom with the pyridyl N-Atom resulting in strong electrostatic interactions between the N and Te Atoms
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Facile cleavage of organochalcogen hybrid (NEEN, NEN, EN, where E=Se or Te) ligand C-E and E-E bonds by Pd(II)
'American Chemical Society (ACS)', 2009Co-Authors: Kaur Rupinder, Panda Snigdha, Singh, Harkesh B., Menon, Saija C., Patel, Rajan P., Butcher, Ray J.Abstract:The synthesis and characterization of chiral hybrid ligand R2∗Se2 (R∗=2-Me2NCH(Me)C6H4) (9) and some of its derivatives is described. The reaction of 9 with a Pd(II) chloride complex leads to cleavage of the Se-Se bond and formation of the corresponding areneselenenyl chloride, R∗SeCl (18). However, reactions of [RS; RS] and [SR; SR] bis[2-{1-(dimethylamine)ethyl}ferrocenyl] diselenides (7 and 8) with a Pd(II) chloride complex under identical conditions afford dinuclear complexes [PdCl{(SeC5H3CH(Me)NMe2-2)Fe(C5H5)}]2 (19 and 20). Reaction of achiral ditelluride, R2Te2 (R=2-Me2NCH2C6H4) (10), with a Pd(II) chloride complex gives a novel dinuclear complex, [PdCl(TeC6H4CH2NMe2-2)]2 (21), and the dimeric Tellurium complex (RTeCl)2 (22), whereas the reaction of chiral Schiff base tridentate Tellurium ligand R'2Te (R'=2-C6H4CH=NCH(Me)C6H5) (11) with a Pd(II) chloride complex produces cleaved products (R'PdCl)2 (23) and (R'TeCl)2 (24). Similarly, the reaction between the tridentate ligand R2Te (12) and Pd(COD)Cl2 gives 22 and the dimeric palladium complex (RPdCl)2 (25). The treatment of bidentate ligand RTeMe (13) results in decomposition of the ligand and precipitation of Te. All the compounds are characterized by detailed IR and NMR (1H, 13C, 77Se, and 125Te) spectroscopic techniques, MS, and optical rotation measurements. The structures of R∗SeBr (17), 21, 24, and 25 were determined by single-crystal X-ray crystallography. In 17 the coordination geometry around selenium is essentially T-shaped with a short Se···N distance (2.132(6) Å). The palladium tellurolato complex 21 crystallizes as a centrosymmetric dimer. Compound 23 crystallizes as a dimer in which each Tellurium Atom coordinates to two bridging chlorines, one nitrogen, and one carbon. Compound 25 crystallizes as a chloro-bridged centrosymmetric dimer
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o-Hydroxylmethylphenylchalcogens: synthesis, intramolecular nonbonded chalcogen···OH interactions, and glutathione peroxidase-like activity
American Chemical Society, 2005Co-Authors: Tripathi, Santosh K., Singh, Harkesh B., Patel Upali, Roy Dipankar, Sunoj, Raghavan B., Wolmershäuser Gotthelf, Butcher, Ray J.Abstract:The synthesis and characterization of a series of organochalcogen (Se, Te) compounds derived from benzyl alcohol 13 are described. The synthesis of the key precursor dichalcogenides 15, 22, and 29 was achieved by the ortho-lithiation route. Selenide 18 was obtained by the reaction of the dilithiated derivative 14 with Se(dtc)2. Oxidation of 15 and 22 with H2O2 afforded the corresponding cyclic ester derivatives 17 and 24, respectively. Oxidation of selenide 18 with H2O2 affords the spirocyclic compound 19. The presence of intramolecular interactions in dichalcogenides 15 and 22 has been proven by single-crystal X-ray studies. The cyclic compounds 17 and 19 have also been characterized by single-crystal X-ray studies. GPX-like antioxidant activity of selenium compounds has been evaluated by the coupled bioassay method. Density functional theory calculations at the mPW1PW91 level on ditelluride 22 have identified a fairly strong nonbonding interaction between the hydroxy oxygen and Tellurium Atom. The second-order perturbation energy obtained through NBO analysis conveys the involvement of nO→σ∗Te-Te orbital overlap in nonbonding interaction. Post wave function analysis with the Atoms in Molecules (AIM) method identified distinct bond critical point in 15 and 22 and also indicated that the nonbonding interaction is predominantly covalent. Comparison between diselenide 15 and ditelluride 22 using the extent of orbital interaction as well as the value of electron density at the bond critical points unequivocally established that a ditelluride could be a better acceptor in nonbonding interaction, when the hydroxy group acts as the donor
Hb Singh - One of the best experts on this subject based on the ideXlab platform.
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Telluroxanes: Synthesis, structure and applications
'Wiley', 2018Co-Authors: Srivastava K, Panda A, Sharma S, Hb SinghAbstract:This review discusses the syntheses, structures and applications of organotelluroxanes. These compounds have found applications in many areas such as catalysis, oxidation, hydrolysis etc. Weak intermolecular O...Te interactions are common features in this class of compounds and play an important role in the aggregation, reactivity and properties of such compounds. However, monomeric species could be isolated by employing bulky groups or intramolecular interactions in the system. The highly polar Te=O double bond in organotelluroxanes imparts very high Lewis acidic character on the Tellurium Atom and is responsible for their unusual reactivity as compared with organoselenium counterparts. (C) 2018 Published by Elsevier B.V
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Facile Cleavage of Organochalcogen Hybrid (NEEN, NEN, EN, where E = Se or Te) Ligand C-E and E-E Bonds by Pd(II)
'American Chemical Society (ACS)', 2009Co-Authors: Kaur R, Hb Singh, Sc Menon, Panda S, Rp Patel, Rj ButcherAbstract:The synthesis and characterization of chiral hybrid ligand R(2)*Se(2) (R* = 2-Me(2)NCH(Me)C(6)H(4)) (9) and some of its derivatives is described. The reaction of 9 with a Pd(II) chloride complex leads to cleavage of the Se-Se bond and formation of the corresponding areneselenenyl chloride, R*SeCl (18). However, reactions of [RS;RS] and [SR; SR] bis[2-{1-(dimethylamine)ethyl}ferrocenyl] diselenides (7 and 8) with a Pd(II) chloride complex under identical conditions afford dinuclear complexes [PdCl{(SeC(5)H(3)CH(Me)NMe(2)-2)Fe(C(5)H(5))}](2) (19 and 20). Reaction of achiral ditelluride, R(2)Te(2) (R = 2-Me(2)NCH(2)C(6)H(4)) (10), with a Pd(II) chloride complex gives a novel dinuclear complex, [PdCl(TeC(6)H(4)CH(2)NMe(2)-2)](2) (21), and the dimeric Tellurium complex (RTeCl)(2) (22), whereas the reaction of chiral Schiff base tridentate Tellurium ligand R'(2)Te (R' = 2-C(6)H(4)CH=NCH(Me)C(6)H(5)) (11) with a Pd(II) chloride complex produces cleaved products (R'PdCl)(2) (23) and (R'TeCl)(2) (24). Similarly, the reaction between the tridentate ligand R(2)Te (12) and Pd(COD)Cl(2) gives 22 and the dimeric palladium complex (RPdCl)(2) (25). The treatment of bidentate ligand RTeMe (13) results in decomposition of the ligand and precipitation of Te. All the compounds are characterized by detailed IR and NMR ((1)H, (13)C, (77)Se, and (125)Te) spectroscopic techniques, MS, and optical rotation measurements. The structures of R*SeBr (17), 21, 24, and 25 were determined by single-crystal X-ray crystallography. In 17 the coordination geometry around selenium is essentially T-shaped with a short Se center dot center dot center dot N distance (2.132(6) angstrom). The palladium tellurolato complex 21 crystallizes as a centrosymmetric dimer. Compound 23 crystallizes as a dimer in which each Tellurium Atom coordinates to two bridging chlorines, one nitrogen, and one carbon. Compound 25 crystallizes as a chloro-bridged centrosymmetric dimer
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O-hydroxylmethylphenylchalcogens: synthesis, intramolecular nonbonded chalcogen center dot center dot center dot oh interactions, and glutathione peroxidase-like activity
'American Chemical Society (ACS)', 2005Co-Authors: Sk Tripathi, Hb Singh, Patel U, Roy D, Rb Sunoj, Wolmershauser G, Rj ButcherAbstract:The synthesis and characterization of a series of organochalcogen (Se, Te) compounds derived from benzyl alcohol 13 are described. The synthesis of the key precursor dichalcogenides 15, 22, and 29 was achieved by the ortho-lithiation route. Selenide 18 was obtained by the reaction of the dilithiated derivative 14 with Se(dtc)(2). Oxidation of 15 and 22 with H2O2 afforded the corresponding cyclic ester derivatives 17 and 24, respectively. Oxidation of selenide 18 with H2O2 affords the spirocyclic compound 19. The presence of intramolecular interactions in dichalcogenides 15 and 22 has been proven by single-crystal X-ray studies. The cyclic compounds 17 and 19 have also been characterized by single-crystal X-ray studies. GP(X)-like antioxidant activity of selenium compounds has been evaluated by the coupled bioassay method. Density functional theory calculations at the mPW1PW91 level on ditelluride 22 have identified a fairly strong nonbonding interaction between the hydroxy oxygen and Tellurium Atom. The second-order perturbation energy obtained through NBO analysis conveys the involvement of n(O) -> sigma*(Te-Te) orbital overlap in nonbonding interaction. Post wave function analysis with the Atoms in Molecules (AIM) method identified distinct bond critical point in 15 and 22 and also indicated that the nonbonding interaction is predominantly covalent. Comparison between diselenide 15 and ditelluride 22 using the extent of orbital interaction as well as the value of electron density at the bond critical points unequivocally established that a ditelluride could be a better acceptor in nonbonding interaction, when the hydroxy group acts as the donor
Caracelli Ignez - One of the best experts on this subject based on the ideXlab platform.
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Bis[(4-methylphenyl)ethynyl] telluride
Wiley-Blackwell, 2010Co-Authors: Caracelli Ignez, Zukerman-schpector Julio, Pena, Jesus M., Stefani, Helio A., Tiekink, Edward R. T.Abstract:The Tellurium Atom in the title bis-ethynyl telluride, Te(C(9)H(7))(2) or C(18)H(14)Te, is located on a crystallographic twofold axis, the C-Te-C angle being 92.23 (15)degrees. The dihedral angle between the rings is 87.27 (7)degrees. In the crystal structure, molecules are connected in chains parallel to the b axis and mediated by C-H center dot center dot center dot pi interactions.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
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Bis[(4-methylphenyl)ethynyl] telluride
WILEY-BLACKWELL, 2010Co-Authors: Caracelli Ignez, Zukerman-schpector Julio, Pena, Jesus M., Stefani, Helio A., Tiekink, Edward R. T.Abstract:The Tellurium Atom in the title bis-ethynyl telluride, Te(C(9)H(7))(2) or C(18)H(14)Te, is located on a crystallographic twofold axis, the C-Te-C angle being 92.23 (15)degrees. The dihedral angle between the rings is 87.27 (7)degrees. In the crystal structure, molecules are connected in chains parallel to the b axis and mediated by C-H center dot center dot center dot pi interactions
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Bis[(4-methylphenyl)ethynyl] telluride
WILEY-BLACKWELL, 2010Co-Authors: Caracelli Ignez, Zukerman-schpector Julio, Pena, Jesus M., Stefani, Helio A., Tiekink, Edward R. T.Abstract:The Tellurium Atom in the title bis-ethynyl telluride, Te(C(9)H(7))(2) or C(18)H(14)Te, is located on a crystallographic twofold axis, the C-Te-C angle being 92.23 (15)degrees. The dihedral angle between the rings is 87.27 (7)degrees. In the crystal structure, molecules are connected in chains parallel to the b axis and mediated by C-H center dot center dot center dot pi interactions.FAPESP[07/59404-2]CNPq[472237/2008-0]CNPq[300613/2007]CNPq[306532/2009-3]CAPES[808/2009
