Ethyl cinnamate is a commonly used flavor, fragrance and pharmaceutical intermediate. Its preparation method is as follows:

Materials: cinnamic acid, ethanol, concentrated sulfuric acid, distilled water

Steps:

1. Weigh an appropriate amount of cinnamic acid powder and add it to the beaker.

2. Add an appropriate amount of ethanol and stir to fully dissolve the cinnamic acid.

3. Add a small amount of concentrated sulfuric acid and heat to boiling. The heating time should be controlled at about 10 minutes.

4. Cool to room temperature and wash twice with distilled water. Then wash with saturated sodium chloride solution to remove sulfuric acid.

5. Use a desiccant to dry and filter to obtain ethyl cinnamate.

The key to preparing ethyl cinnamate is to add a small amount of concentrated sulfuric acid to promote the reaction, but the heating and cooling times need to be mastered to avoid producing undesirable reaction products. At the same time, it is also necessary to strictly control the reaction temperature and safety measures during operation.