Dehydroacetic acid
 | This article is missing information about etymology/history of discovery (where does the dehydro come from?); biocide mechanism of action; pKa. (August 2022) |
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| Names | |
|---|---|
| Preferred IUPAC name
3-Acetyl-2-hydroxy-6-methyl-4H-pyran-4-one | |
| Other names | |
| Identifiers | |
3D model (JSmol)
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| Abbreviations | DHAA |
| ChEBI | |
| ChEMBL | |
| ChemSpider | |
| ECHA InfoCard | 100.007.541 |
| EC Number |
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| E number | E265 (preservatives) |
| MeSH | dehydroacetic+acid |
PubChem CID
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| UNII | |
CompTox Dashboard (EPA)
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| Properties | |
| C8H8O4 | |
| Molar mass | 168.148 g·mol−1 |
| Appearance | White crystals |
| Melting point | 109 °C; 228 °F; 382 K |
| Boiling point | 270 °C; 518 °F; 543 K |
| Hazards | |
| GHS labelling: | |
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| Warning | |
| H302 | |
| P264, P270, P301+P312, P330, P501 | |
| NFPA 704 (fire diamond) | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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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.[2]
Preparation[edit]
It is prepared by the base-catalysed dimerization of diketene.[3] Commonly used organic bases include imidazole, DABCO, and pyridine.[4]
Uses[edit]
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.[5] 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.[1]
- 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.[6]
References[edit]
- ^ Jump up to: a b Merck Index, 11th Edition, 2855
- ^ Jilalat, Alae Eddine; et al. (2017). "DEHYDROACETIC ACID (Part 1): CHEMICAL AND PHARMACOLOGICAL PROPERTIES". Journal Marocain de Chimie Hétérocyclique. 16 (1): 1–47. ISSN 1114-7792. Retrieved July 3, 2017.
- ^ Raimund Miller, Claudio Abaecherli, Adel Said, Barry Jackson. "Ketenes". In Ullmann's Encyclopedia of Industrial Chemistry. 2001, Wiley-VCH, Weinheim. doi:10.1002/14356007.a15_063
- ^ Clemens, Robert J.; Witzeman, J. Stewart (1993). Agreda, Victor H.; Zoeller, Joseph R. (eds.). Acetic Acid and its Derivatives. New York: Marcel Dekker, Inc. p. 202. ISBN 9780824787929.
- ^ Harold William Rossmoore. Handbook of Biocide and Preservative Use, p. 341. ISBN 0-7514-0212-5
- ^ Cook, Denys (1963). "The Preparation, Properties, and Structure of 2,6-bis-(Alkyamino)-2,5-heptadien-4-ones". Canadian Journal of Chemistry. 41 (6): 1435–1440. doi:10.1139/v63-195.