| 摘要 |
PURPOSE:To prepare 1,3-diones, useful as intermediates of drugs, pesticides, and perfumes, easily, in high yield, under mild conditions, by specifically isomerizing specific 2,3-epoxy-1-ones in the presence of a catalyst. CONSTITUTION:A 2,3-epoxy-1-one of formula I (R1,2 are 1-10C organic group; R1 and R2 may form a ring) is isomerized in the presence of a catalyst such as metallic Pd or Pd chloride, at 0-200 deg.C, pref. 10-150 deg.C, to obtain the title compound of formula II. The amount of the catalyst is 25-0.0001wt%, pref. 0.5- 0.001wt%, based on the raw material. Preferably, a tri-organo-phosphine (pref. triphenyl phosphine) is added to the catalyst as a cocatalyst, if necessary. |
