5159-42-2Relevant articles and documents
Electron Transfer Reactions in Organic Chemistry. VII. Oxidative Acetoxylation of Aromatic Compounds by Tungsten Hexachloride
Eberson, Lennart,Joensson, Lennart,Saenneskog, Owe
, p. 113 - 122 (2007/10/02)
Tungsten hexachloride, a high-potential oxidant, causes fast oxidative acetoxylation of ring and/or α positions of aromatic compounds, even as difficalty oxidizable ones as mesitylene and p-xylene.Chlorination is a completing reaction which cannnot be completely suppressed.The acetoxylation process in all likelihood proceeds via an electron transfer mechanism, involving initial formation of the radical cation of the substrate.
The Liquid-phase Oxidation of the Methylbenzenes by the Cobalt-Copper-Bromide System
Okada, Toshihiko,Kamiya, Yoshio
, p. 2724 - 2727 (2007/10/02)
The liquid-phase oxidation of the methylbenzenes catalyzed by a catalyst system composed of cobalt(II) and copper(II) acetates and sodium bromide was carried out in the acetic acid at 150 deg C.The corresponding benzyl acetates and benzaldehydes were obtained in high selectivities in most cases.A nuclear-brominated product, i.e., 3-bromo-4-methoxytoluene was also obtained in the oxidation of p-methoxytoluene, wich has two different reaction sites, i.e., o-positions to the electron-donating methoxyl substituent and the benzyl position.However, the substitution of the bromide ion for the acetate ion in the catalyst system gave satisfactory selectivities for the side-chain oxidation products.In the p-xylene oxidation, α,α'-diacetoxy-p-xylene and p-(acetoxymethyl)benzoic acid were also obtained, as well as p-methylbenzyl acetate, though their amounts were small.The oxidation of polymethylbenzenes was also carried out.
Metal Ion Oxidation. VII. Oxidation of Aromatic Hydrocarbons by Potassium 12-Wolframocobalt(III)ate, a "Soluble Anode"
Eberson, Lennart,Wistrand, Lars-Goeran
, p. 349 - 358 (2007/10/02)
The oxidation of aromatic compounds with potassium 12-wolframocobalt(II)ate in acetic acid media has been investigated.A wide range of alkylaromatics can be acetoxylated in the α position, whereas nuclear substitution can be effected in the presence of acetate ion.In a few cases acetoxymethylation is observed, presumably via intermediate arylacetic acid. 4-Fluoroanisole is converted to 4-acetoxyanisole.In all preparative aspects, the reaction is closely similar to anodic and Ag(II) mediated acetoxylation.A study of substituted effects upon α acetoxylation showed a good linear relationship between log krel and Eo for oxidation of the alkylaromatic substrates (slope -3.2 V-1).A strong deuterium isotope effect (KH/kD ca. 6) is indicative of a rate-determining step involving hydrogen atom transfer ("concerted electron/proton transfer") from the α C-H bond to an oxygen of the heteropoly ion.