| 摘要 |
PURPOSE:To obtain a lactone useful as a raw material for preparing a polyester, etc. at a high rate of reaction and selectivity, by reducing an alicyclic acid anhydride or an acid containing hydrous acid thereof under pressure in the presence of a ruthenium catalyst. CONSTITUTION:A compound of formulaIor II[A is a group of formula III or IV (R1 and R2 are H or 1-4C alkyl)]is catalytically hydrogenated in the presence of a ruthenium catalyst to give a lactone of formula V (B is a group of formula V), e.g. hexahydrophthalide. Simple metallic ruthenium may be used as the ruthenium catalyst, and 1-5% expressed in terms of ruthenium, catalytic component is preferably supported on carbon, alumina or silica asbestos, etc. as a carrier. The amount of the catalyst to be used is preferably 0.05-0.5% expressed in terms of ruthenium based on the raw material. The reaction temperature is 150-200 deg.C, and the hydrogen gas pressure is 30-70kg/cm<2>.G. |
