Preparation of coumaryl alcohol

Joseph Sampson, 10/21/21

This is a continuation of a project started in 2018 by A. Tibbs.

Coumaryl alcohol is a monomer of lignin.

Coumaryl alcohol will be synthesized from coumaric acid through two separate reactions:

1. First, coumaric acid will be converted into ethyl coumarate by through esterification. This will involve converting the carboxylic acid group into an ethyl ester group.
2. Finally, ethyl coumarate will be converted into coumaryl alcohol through a reduction reaction.

The experiment performed is based off of a published paper in which the authors previously synthesized coumaryl alcohol. The "Synthesis of p-Coumaryl Alcohol" subheading is what's important.

• Initial procedure for the Synthesis of Coumaryl Alcohol (simplified):

1. Add 1g (0.0061 moles) of p-Coumaric acid and 5mL (0.07 moles) acetyl chloride into a round bottom flask containing 50mL of dry ethanol. The total concentrations of coumaric acid and acetyl chloride in solution should be 0.111M and 1.27M each.
2. Stir at room temperature for 17 hours.
3. After 17 hours, evaporate the solvent.
4. Repeat steps 1-3 again.
5. Recrystallize the product from ethyl acetate (product should be ethyl p-coumarate).