32344-00-6Relevant academic research and scientific papers
Experimental and theoretical studies on formal σ-bond metathesis of silyl tellurides with alkyl halides
Yamago, Shigeru,Iida, Kazunori,Yoshida, Jun-ichi
, p. 664 - 670 (2008/02/06)
Silyl tellurides reacted with alkyl halides under mild thermal conditions to give the corresponding alkyl tellurides and silylhalides in good to excellent yields. Substitution took place much faster in polar solvents, such as acetonitrile, than that in no
A new, practical synthesis of organotellurium compounds from organic halides and silyl tellurides. Remarkable effects of polar solvents and leaving groups
Yamago, Shigeru,Iida, Kazunori,Yoshida, Jun-ichi
, p. 5061 - 5064 (2007/10/03)
Silyl tellurides react with organic halides to give the corresponding organotellurium compounds and silyl halides in good to excellent yields. Substitution proceeds in polar solvents, such as acetonitrile, but not in nonpolar solvents under identical conditions. The leaving group also plays a significant role, with alkyl bromides being the most reactive, alkyl chlorides less so and alkyl iodides the least reactive. After removal of the volatile silyl halides and solvent under vacuum, the essentially pure organotellurium compounds, which can be used directly as precursors for carbocations, carbanions, and carbon-centered radicals, were obtained.
Reactions of Alkylmercurials with Heteroatom-Centered Acceptor Radicals
Russell, Glen A.,Ngoviwatchai, Preecha,Tashtoush, Hasan I.,Pla-Dalmau, Anna,Khanna, Rajive K.
, p. 3530 - 3538 (2007/10/02)
The relative reactivities of alkylmercury halides toward PhS., PhSe., or I. decrease drastically from R = tert-butyl to R = sec-alkyl to R = n-butyl, indicative that R. is formed in the rate-determining step in the attack of these radicals upon RHgCl.The alkyl radicals thus formed will enter into chain reactions in which a heteroatom-centered radical (A.) is regenerated from substrates such as RS-SR, ArSe-SeAr, ArTe-TeAr, PhSe-SO2Ar, Cl-SO2Ph; ZCH=CHA (A = Cl, I, SPh, SO2Ph); or PhCCHA (A = I, SPh, SO2Ph). β-Styrenyl (PhCH=CHA, Ph2C=CHA) and β-phenethynyl (PhCCA) systems with A = I, Br, SO2Ph also enter into chain reactions with mercury(II) salts with the ligands PhS, PhSe, PhSO2, or (EtO)2PO.The relative reactivities of a series of reagents toward t-Bu. and of PhCH=CHA, Ph2C=CHA, and PhCCA toward c-C6H11. are reported as well as the regioselectivity of t-Bu. attack observed for 1,2-disubstituted ethylenes (ZCH=CHA) with Z and A from the group Ph, Cl, Br, I, SO2Ph, SPh, Bu3Sn.Reactions of (E)- and (Z)-PhCH=CHI or MeO2CCH=CHI with t-Bu. or c-C6H11. occurred in a regioselective and stereospecific (retention) manner.Reactions of (E)- and (Z)-ClCH=CHCl occurred in a nonstereospecific manner in which the E/Z product ratio increased with the bulk of the attacking radical.A similar effect on the E/Z product ratios was observed for (Z)-MeO2CCH=CHCl.
CATALYTIC OXIDATION OF OLEFINS USING DIPHENYL DITELLURIDE
Kambe, Nobuaki,Fujioka, Toyozo,Ogawa, Akiya,Miyoshi, Noritaka,Sonoda, Noboru
, p. 167 - 176 (2007/10/02)
Reaction of aliphatic olefins with tert-butyl hydroperoxide and diaryl ditellurides in the presence of sulfuric acid in refluxing methanol gave methoxytellurenylation products with high regioselectivity having the aryltelluro group on the terminal carbon in the case of terminal olefins.The stereochemistry of the product from cyclohexene was trans.Under similar conditions, aromatic substituted olefins afforded vic-dimethoxyl compounds in the presence of catalytic amount of diaryl ditelluride.In this reaction, molecular oxygen (or air) as well as peroxidesand peracids were found to be effective as the oxidizing agent.The catalytic oxidation of olefins reported here proceeded in net syn fashion probably via anti methoxytellurenylation followed by displacement of the phenyltelluro group by a methoxy group with inversion.
NUCLEOPHILIC CLEAVAGES OF ESTERS AND ETHERS WITH PHENYLTELLUROTRIMETHYLSILANE
Sasaki, Kazuaki,Aso, Yoshio,Otsubo, Tetsuo,Ogura, Fumio
, p. 453 - 456 (2007/10/02)
The title tellurosilane 1 reacted with esters and ethers in the presence of catalytic zinc iodide under very mild conditions, giving the corresponding products with C-telluration and O-silylation via nucleophilic cleavages of the C-O bonds.
ALKALINE HYDROLYSIS OF DIARYL DITELLURIDES UNDER PHASE TRANSFER CONDITIONS; SYNTHESIS OF ALKYL ARYL TELLURIDES
Comasseto, J. V.,Ferreira, J. T. B.,Val, Fontanillas
, p. 261 - 266 (2007/10/02)
The disproportionation reaction of diaryl ditellurides with sodium hydroxide under phase transfer conditions at room temperature is described for the first time.The phase transfer catalyst used is 2HT-75, a trade name for a mixture of dialkyldimethylammonium chlorides.The intermediates aryl tellurolates react "in situ" with alkyl halides to give the corresponding alkyl aryl tellurides (ArTeR) in 52-72percent yield.The following compounds were prepared: Ar = C6H5, R = CH3(CH2)3CH2,(CH3)2CHCH2CH2, (CH3)2CHCH2, CH3CHBrCH2CH2, CH3(CH2)8CH2, C6H5CH2, ClCH2, C6H5CH2CH2, CH2=CHCH2, C6H5CH=CHCH2, C6H5SeCH2, ; Ar = p-CH3C6H4, R = CH3(CH2)2CH2; Ar = p-CH3OC6H4, R = CH3(CH2)2CH2; Ar = p-C2H5OC6H4, R = CH3(CH2)2CH2; Ar = 2-naphthyl, R = CH3(CH2)2CH2.
