Discussion on the preparation of 3,4,5-trimethoxy cinnamic acid
raw materials and preparation
To prepare 3,4,5-trimethoxy cinnamic acid, first prepare all kinds of raw materials. It is necessary to take an appropriate amount of 3,4,5-trimethoxy benzaldehyde, which is the basis for the initiation of the reaction. Its quality must be pure and the amount should be accurate to ensure a smooth reaction. And prepare malonic acid, which is also the key. The ratio of the two is related to the success or failure of the reaction, and it must be weighed in a rigorous manner and according to the ratio. In addition, pyridine is also indispensable. It is in the reaction and has the ability to catalyze, which can promote the reaction to accelerate.

Process of Reaction
Pour the prepared 3,4,5-trimethoxybenzaldehyde and malonic acid into a clean reaction vessel in sequence. The vessel needs to be dry and free of impurities to prevent impurities from interfering with the reaction. Next, add pyridine slowly, and the action should be slow to avoid violent reaction. After adding it, place the reaction vessel in a specific temperature environment, and use a temperature control device to precisely adjust the temperature, so that the reaction can be carried out at a suitable heat. During the reaction, if you look closely, you can see that the liquid in the container gradually changes, the color may change, or there are bubbles escaping, which are all signs of the reaction. Be patient, so that the reaction is sufficient, and do not rush too quickly, causing the reaction to be unfinished.

Purification of the product
When the reaction is over, the resulting product may contain impurities such as unreacted raw materials, by-products and catalysts, so purification is imperative. First dissolve the product with an appropriate solvent. The choice of solvent depends on the characteristics of the product, so that the product is easily soluble and the impurities are difficult to dissolve. After dissolving, a filtration method is applied to remove its insoluble impurities. The filtrate is then distilled to gradually remove the solvent, leaving the concentrated product. However, the product is still not pure, and the method of recrystallization is used to further purify it. Choose a suitable solvent, heat the product to dissolve, and then slowly cool down to make the product crystallize and precipitate. At this time, the resulting crystal is relatively pure 3,4,5-trimethoxy cinnamic acid.

After this operation, 3,4,5-trimethoxy cinnamic acid of high quality can be obtained, which lays a solid foundation for subsequent use. Although the preparation process is cumbersome and requires caution, strict adherence to the procedures will surely lead to satisfactory results.