| 摘要 |
PURPOSE:To advance reaction in a short time under mild condition, prevent formation of tarry materials, etc., and obtain an acid anhydride, by carrying out the exchange reaction of an organic carboxylic acid with a carboxylic acid in the presence of a specific metallic ion as a catalyst. CONSTITUTION:An organic carboxylic acid anhydride, e.g. acetic anhydride, etc., and a carboxylic acid such as substituted or unsubstituted aliphatic carboxylic acid, e.g. propionic acid, are subjected to exchange reaction at 10 deg.C - the boiling point of the raw materials in the presence of >=5ppm one or more metallic ions selected from Co, Ni, Mn, Fe, Li, Na, K, Mg, Ca, Cu, An, Al, Ti and V, preferably ions, e.g. Co, Ni, Mn, etc., to afford the aimed acid anhydride. The organic carboxylic acid anhydride to be used is used in an amount of 1 equivalent or more based on the carboxylic acid. the metallic ions are used as metallic salts, e.g. nitrate, acetate, etc., hydroxides, chlorides, etc. EFFECT:Synthesis of thermally unstable substances can be carried out. |
