| abstract |
The invention relates to a preparation method of dimethyl 3-aminophthalate, which comprises the following steps: taking 3-nitrophthalic acid as a starting material, adding a certain amount of methanol, and heating at 40-60°C Under stirring and dissolving, methanol is both a solvent and a reaction raw material; a certain amount of thionyl chloride is added dropwise for heat preservation reaction, and concentrated in vacuum to obtain a 3-nitrophthalate intermediate, which is crystallized and purified; In the environment, under the action of a certain amount of palladium carbon, add a certain proportion of 3-nitrophthalate dimethyl ester intermediate and methanol, react at room temperature, the reaction is over, and after vacuum concentration, 3-aminophthalate dicarboxylate is obtained. methyl ester. The reaction raw materials are relatively easy to obtain, the price is reasonable, the reaction conditions are mild, the operation is easy, the control is easy, the post-treatment is simple, and the product quality is stable and the purity is high. |