Caffeic acid is an organic acid, which exists in honeysuckle, thistle, wormwood and other plants in nature. Its appearance is yellow crystal, and it usually exists in the form of glucoside and ester. Caffeic acid is not only a metabolite of lignin synthesis pathway, but also an intermediate product of phenylpropane metabolism pathway in tobacco.
To obtain caffeic acid, we can obtain it through chemical synthesis, for example, with catechins as raw materials, through substitution, oxidation, addition and other reactions can produce caffeic acid. Caffeic acid can also be prepared by 3-methoxy-4-hydroxybenzaldehyde, 3, 4-dimethoxy-benzaldehyde, 3, 4-dimethoxy-benzaldehyde, 3, 4-methylene benzaldehyde and substituted cinnamate esters through corresponding condensation, demethylation, hydrolysis and other chemical reaction.
Not all of the above preparation methods are suitable for industrial production. For the production of caffeic acid, we advocate green, environmental protection, scientific and reasonable concept, in line with sustainable development.