| 摘要 |
1,139,507. Peracids. DISTILLERS CO. Ltd. 9 May, 1966 [20 April, 1965], No. 16446/65. Heading C2C. Mono-percarboxylic acids are prepared by reacting hydrogen peroxide with the anhydride of a dicarboxylic acid in the presence of a liquid which is miscible with hydrogen peroxide and which has a dielectric constant greater than 20, provided that said liquid does not comprise solely water or sulphuric acid. It is preferred to use substantially inert organic liquids, e.g. N,N-dialkyl formamides, N-alkyl pyrrolidones and formic acid. The reaction mixture may also include a high dielectric liquid which is not miscible with hydrogen peroxide, e.g., nitromethane and nitrobenzene, or a low dielectric liquid, e.g. chloroform. It is preferred to use aqueous hydrogen peroxide having a concentration greater than 80% w./w. and to effect the reaction at a temperature below 50‹ C. Examples relate to the preparation of mono-peracids from maleic, phthalic and succinic anhydrides. The mono-peracid may be used to oxidize cyclohexanone to caprolactone. |
