| 摘要 |
e -Caprolactones of the formula <FORM:1070323/C2/1> are made by contacting a cyclohexanone of the formula <FORM:1070323/C2/2> where R represents hydrogen or an alkyl or cycloalkyl group, with a pre-formed solution of hydrogen peroxide and formic acid in the absence of a catalyst at 0 DEG to 40 DEG C., in the proportion of at least 1 mol formic acid per mol hydrogen peroxide, the molar ration of hydrogen peroxide/cyclohexanone being between 0.1 and 2. A small proportion of crystalline cyclic peroxides may form in the reaction mixture. It is preferred to allow the mixture of hydrogen peroxide and formic acid to stand for sufficient time for 20-80% of the hydrogen peroxide to be converted to performic acid. The caprolactones are separated from the reaction mixture at temperatures below 40 DEG C., e.g. by using thin film distillation or solvent extraction. Examples are provided. |
