2207-75-2

64-19-7

97-59-6

2207-75-2

The general procedure for synthesizing potassium oxonate from glacial acetic acid and allantoin was as follows: 3.2 kg of potassium hydroxide was dissolved in 11.4 L of water, added to a 20 L reactor to dissolve, and then cooled to 0~5 °C. 46 g of potassium iodide was added, and 0.9 kg of allantoin was added in batches and stirred until completely dissolved, keeping the temperature at 0~5 °C. Subsequently, 1.8 kg of bromine was slowly added dropwise, and the dropwise time was controlled at 9 hours (the experiment was divided into the first 1-8 groups according to the difference of bromine dropwise time). After the dropwise addition was completed, stirring was continued at 0~5°C for 1 h. Then the temperature was increased to 20~25°C and the reaction was kept at this temperature for 20 h. The reaction was carried out by HPLC. After confirming that the allantoin content was less than 0.6% by HPLC, the reaction solution was cooled to 0~5°C. The pH was adjusted to 5 with acetic acid and the reaction solution was filtered. The filter cake was washed with 3 L of water at 0~5°C and then with 1 L of room temperature ethanol. Finally, potassium oxonate was allowed to precipitate from a white potassium oxide crystalline solid at room temperature.