CAN- and DDQ-Promoted Oxidation of Alkenyl Sulfides
作者:Laura Capella、Pier Carlo Montevecchi、Daniele Nanni
DOI:10.1021/jo00103a033
日期:1994.12
Vinyl sulfides 1 react with CAN in acetonitrile at room temperature to give radical cations 2A in equilibrium with the thiiranyl radical cations 2B. The reaction products arise from nucleophilic attack of the nitrate counterion at either the sulfur atom of 2A or the trivalent carbon of 2B. The last reaction can proceed through 1,2-shift or displacement of the sulfide moiety. When alpha-methylenic protons are present in 2B, deprotonation occurs, leading to allyl radicals and, ultimately, to isomeric allyl alcohols. Reactions of 1 with DDQ in acetonitrile afford charge-transfer complexes and then zwitterionic electron-transfer (ET) complexes which can evolve rapidly through intramolecular proton transfer when trans methylenic protons are present. The resulting sulfur-oxygen sigma-complexes are responsible for the reaction products mainly through either gamma-elimination of DDQH(2) or nucleophilic attack at the delta-vinylic carbon followed by displacement of DDQH(-).
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作者:N. V. Kuz'mina、E. S. Lipina、T. Yu. Kropotova、G. A. Berkova、Z. F. Pavlova
DOI:10.1023/a:1013119318658
日期:——
Reactions of 1-nitro-2-sulfonylalkenes with arenethiolates result in replacement of the sulfonyl group; the reactions with alkanethiolates are accompanied by subsequent addition of the reagent at the double bond to afford thioacetals. Less reactive alpha-nitro-beta-R-thiostyrenes with thiolates at reduced temperature form addition products which are converted into the corresponding substitution products on storage at room temperature, in keeping with the addition-elimination mechanism of nucleophilic vinyl substitution. Nitro(aryl-thio)- and nitro(heterylthio)alkenes react with alkanethiolates at room temperature, resulting in replacement of the arylthio (heterylthio) group by alkylthio.
Reactions of 1,2-dinitro- and 1-nitro-2-sulfonylethenes with some binucleophiles
作者:T. Yu. Kretser、E. S. Lipina、N. V. Kuz’mina、G. A. Berkova
DOI:10.1134/s1070428010080221
日期:2010.8
Pavlova; Lipina; Kasem, Russian Journal of Organic Chemistry, 1999, vol. 35, # 9, p. 1321 - 1325