| 摘要 |
1,155,570. # - Hydroxycarboxylic acids. COURTAULDS Ltd. 19 Oct., 1966 [20 Oct., 1965; 22 Nov., 1965; 4 March, 1966; 22 April, 1966], Nos. 44364/65, 49538/65, 9507/66 and 17659/66. Heading C2C. Saturated aliphatic #-hydroxy carboxylic acids and ester derivatives thereof are prepared by the oxidation of an alicyclic ketone by heating a solution of hydrogen peroxide or a ketone peroxide and a free heteropoly acid catalyst with an excess of the substantially anhydrous alicyclic ketone. Cyclobutanone, cyclopentanone, cyclohexanone, cycloheptanone are mentioned which produce 4-hydroxybutyric, 5- hydroxyvaleric, 6-hydroxycaproic, 7-hydroxyenanthie acids and/or the lactones and polyesters thereof respectively. The ketone peroxide which preferably contains the ketone residue corresponding to the acyclic ketone is an equilibrium mixture of a 1-hydroxy-cycloalkyl hydroperoxide and its bis- and tris-polymers and the preparation of a cyclohexanone peroxide equilibrium mixture is described. Many heteropoly acids are listed. Examples describe the preparation of 6-hydroxycaproic acid from cyclohexanone, cyclohexanol hydroperoxide and 12-tungstophosphoric acid and adipic acid and adipaldehyde are by-products; 5-hydroxyvaleric acid from cyclopentanone, cyclohexanone peroxide and 12-tungstophosphoric acid. The reactions may be batchwise or continuous and an apparatus suitable for continuous operation is described. |
