Dehydroacetic acid explained

Dehydroacetic acid is an organic compound which has several industrial applications. The compound is classified as a pyrone derivative. It presents as an odorless, colorless to white crystalline powder, almost insoluble in water and moderately soluble in most organic solvents.^[1]

Preparation

It is prepared by the base-catalysed dimerization of diketene.^[2] Commonly used organic bases include imidazole, DABCO, and pyridine.^[3]

Uses

Industrially, dehydroacetic acid has several uses which include the following:

• as a fungicide and bactericide. The sodium salt, sodium dehydroacetate, is often used in place of dehydroacetic acid because of its greater solubility in water.
• as a food preservative to prevent pickle bloating in squash and strawberries.^[4] When used as a food additive, dehydroacetic acid is referred to using the International Numbering System for Food Additives or E number 265.
• as a plasticizer in synthetic resins.
• as an antienzyme in toothpastes.
• as a precursor for dimethyl-4-pyridones. The compounds are synthesized when dehydroacetic acid is exposed to aqueous solutions containing primary amines.^[5]

Notes and References

1. Jilalat . Alae Eddine . etal . 2017 . DEHYDROACETIC ACID (Part 1): CHEMICAL AND PHARMACOLOGICAL PROPERTIES . Journal Marocain de Chimie Hétérocyclique . 16 . 1 . 1–47 . 1114-7792. July 3, 2017.
2. Raimund Miller, Claudio Abaecherli, Adel Said, Barry Jackson. "Ketenes". In Ullmann's Encyclopedia of Industrial Chemistry. 2001, Wiley-VCH, Weinheim.
3. Book: Clemens. Robert J.. Witzeman. J. Stewart. Agreda. Victor H.. Zoeller. Joseph R.. Acetic Acid and its Derivatives. 1993. Marcel Dekker, Inc.. New York. 9780824787929. 202.
4. Harold William Rossmoore. Handbook of Biocide and Preservative Use, p. 341.
5. Cook . Denys . The Preparation, Properties, and Structure of 2,6-bis-(Alkyamino)-2,5-heptadien-4-ones . Canadian Journal of Chemistry . 1963 . 41 . 6 . 1435–1440 . 10.1139/v63-195. free .