The method of making barbituric acid
If you want to make barbituric acid, you should understand the reasons and follow the method to achieve the requirements.

First of all, you need to prepare all kinds of materials. The required things are diethyl malonate and urea. These two are the main materials for making barbituric acid, and they must be selected to ensure its purity. Adjuvants such as ethanol and sodium metal need to be prepared. If the ethanol needs to be of high purity, the sodium metal must also be of high quality and flawless.

When preparing, first take an appropriate amount of ethanol in a clean vessel, and carefully put the sodium metal into it. When sodium is added to ethanol, it will react immediately. It is better to stir it slowly to make the reaction uniform and stable. When the sodium is completely dissolved, this solution is a solution of sodium ethyl alcohol, which is an important catalyst in the reaction of preparing barbituric acid.

Then, diethyl malonate is slowly added to the above sodium ethyl alcohol solution, and the time should be added slowly, and the stirring should be kept to make the two fully miscible. After diethyl malonate is added, the solution gradually changes. At this time, the temperature should be controlled, not too high or too low, and a suitable water temperature bath is often used to maintain a constant temperature.

When diethyl malonate is properly mixed with sodium ethyl alcohol solution, urea is slowly added. After urea is added, the reaction becomes more and more complicated, and it is still necessary to carefully check the temperature and stirring degree. During the reaction, various molecules interact, chemical bonds are broken and recombined, and the embryonic form of barbituric acid is gradually formed.

After the reaction is completed, the resulting mixture still contains impurities. At this time, separation and purification are required. First, the insoluble impurities are removed by an appropriate filtration method. Then, volatile substances such as ethanol are removed by distillation. Then, by recrystallization, the barbituric acid precipitates pure crystals from the solution. When recrystallizing, choose an appropriate solvent, control the temperature and time, and make the crystal perfectly formed.

In this way, through material preparation, reaction operation, separation and purification steps, pure barbituric acid can be obtained. When preparing, each step needs to be rigorous, and a slight difference will affect the quality and quantity of the product.