Mar. 10, 2021
Cinnamic acid is a white crystalline compound that is slightly soluble in water and freely soluble in many organic solvents. Classified as an unsaturated carboxylic acid, it occurs naturally in many plants. It exists as cis and trans isomers, although the latter is more common.
It is obtained from cinnamon oil or balsam (e.g. honey balsam). It is also found in tallow resin. Cinnamic acid has a honey-like odour. It and its various volatile ethyl esters (ethyl cinnamate) are the aroma components of the essential oil cinnamon, of which the related cinnamaldehyde is the main component.
Cinnamic acid is first synthesised by the base catalysed condensation of acetyl chloride and benzaldehyde, followed by the acyl chloride product of hydrolysis. In 1890, Rainer Ludwig Claisen described the synthesis of ethyl cinnamate by the reaction of ethyl acetate with benzaldehyde in the presence of sodium as a base. An alternative method for the preparation of cinnamic acid is the Knoevenagel condensation reaction.  The reactants for this purpose are benzaldehyde and malonic acid in the presence of a weak base followed by an acid-catalyzed decarboxylation reaction. It can also be prepared by oxidation of cinnamaldehyde, condensation of benzoyl chloride and sodium acetate (followed by acid hydrolysis) and the Perkin reaction. The oldest commercially available route to cinnamic acid involves the Perkin reaction.
Cinnamic acid is used in flavouring agents, in the synthesis of indigo and in certain pharmaceuticals. The main use is as a precursor in the flavour industry for the production of methyl cinnamate, ethyl cinnamate and benzyl cinnamate. Cinnamic acid is a precursor to the sweetener aspartame, which is produced by enzyme-catalyzed amination to produce phenylalanine. Cinnamic acid can dimerise in non-polar solvents, resulting in different linear free energy relationships.
1. Can be used as a fragrance mixture in soap, shampoo, washing powder, daily cosmetics.
2. Cinnamic acid can be used to adjust apples and cherries. It can be used as apple flavor, cherry flavor, fruit flavor and flower flavor.
3. Anti-mildew, antisepsis and sterilization using cinnamic acid can be applied to freshness and antisepsis in food, vegetables and fruits.
4. In the pharmaceutical industry, the important drugs used in the treatment of coronary heart disease are lactamidine and Xintongping, and chloramphenicol and cinnamophenazine, which are used to make "Xinan'an", a local anesthetic, bactericide, and hemostatic agent. Medicine, etc.
5. Cinnamic acid also has a good aroma-preserving effect. It is usually used as a raw material for fragrance and is used as a fixative in daily fragrance.
6. In the agricultural industry, cinnamic acid is used as a growth promoter and long-lasting fungicide for fruit and vegetable preservation.
7. In organic chemical synthesis, cinnamic acid can be used as a slow-release agent for galvanized sheet, a heat stabilizer for polyvinyl chloride, a crosslinking agent for polyurethane, a flame retardant for hydantoin and polycaprolactam, and a chemical analysis reagent.
The above information is provided by the Cinnamic acid manufacturer.