| Identification | More | [Name]
Dehydroacetic acid | [CAS]
520-45-6 | [Synonyms]
2-ACETYL-5-HYDROXY-3-OXO-4-HEXENOIC ACID DELTA-LACTONE
2-ACETYL-5-HYDROXY-3-OXO-4-HEXENOIC ACID D-LACTONE
2-ACETYL-5-HYDROXY-3-OXO-4-HEXENOIC ACID GAMMA-LACTONE
3-ACETYL-3,4-DIHYDRO-6-METHYL-2H-PYRAN-2,4-DIONE
3-ACETYL-4-HYDROXY-6-METHYL-2H-PYRAN-2-ONE
3-ACETYL-4-HYDROXY-6-METHYL-2-PYRONE
3-ACETYL-6-METHYL-2H-PYRAN-2,4(3H)-DIONE
3-ACETYL-6-METHYL-2H-PYRONE-2,4-(3H)-DIONE
DEHYDRACETIC ACID
DEHYDRANONE
DEHYDROACETIC ACID
DHA
LABOTEST-BB LT00053173
2-acetyl-5-hydroxy-3-oxo-4-hexenoicacidelta-lactone
2-Acetyl-5-hydroxy-3-oxo-4-hexenoicacid-lactone
2H-Pyran-2,4(3H)-dione, 3-acetyl-6-methyl-
2H-Pyran-2-one, 3-acetyl-4-hydroxy-6-methyl-
3-acetyl-4-hydroxy-6-methyl-2h-pyran-2-on
3-Acetyl-4-hydroxy-6-methyl-2-pyrone cyclic ketone
3-Acetyl-6-methyl-2,3-dihydropyran-2,4-dione | [EINECS(EC#)]
212-227-4 | [Molecular Formula]
C8H8O4 | [MDL Number]
MFCD00066709 | [Molecular Weight]
168.15 | [MOL File]
520-45-6.mol |
| Chemical Properties | Back Directory | [Appearance]
white to light yellow crystal powder | [Melting point ]
111-113 °C (lit.) | [Boiling point ]
270 °C (lit.) | [density ]
1.1816 (rough estimate) | [vapor pressure ]
0.001 hPa (20 °C) | [refractive index ]
1.4611 (estimate) | [Fp ]
157°C | [storage temp. ]
0-6°C | [solubility ]
2g/l | [form ]
Fine Crystalline Powder | [pka]
5.53±0.40(Predicted) | [color ]
Light yellow or cream | [Odor]
almost odorless. slightly bitter-sweet taste. | [PH]
4 (2g/l, H2O, 20℃) | [Stability:]
Stable. Incompatible with oxidizing agents, bases, reducing agents. | [Water Solubility ]
500mg/L at 25℃ | [Usage]
Geogard(R) 221 preservative is based on dehydroacetic acid (DHA) and benzyl alcohol, and therefore is recognized by major cosmetic, toiletry and fragrance regulatory authorities worldwide for use in cosmetic and personal care products. | [Detection Methods]
HPLC,NMR | [Merck ]
14,2865 | [BRN ]
6129 | [InChIKey]
PGRHXDWITVMQBC-UHFFFAOYSA-N | [LogP]
0.78 at 20℃ | [Uses]
Dehydroacetic Acid (DHA) is a preservative that is a crystalline powder with a solubility of less than 0.1 g in 100 g of water at 25°C. It can undergo a variety of chemical reactions which give it utility in many applications. It is used at 0.01–0.5% for microbiological growth inhibition in various foods. It is used for cut or peeled squash, with no more than 65 ppm remaining in or on the prepared squash. | [CAS DataBase Reference]
520-45-6(CAS DataBase Reference) | [NIST Chemistry Reference]
Dehydroacetic Acid(520-45-6) | [EPA Substance Registry System]
520-45-6(EPA Substance) |
| Safety Data | Back Directory | [Hazard Codes ]
Xn | [Risk Statements ]
R22:Harmful if swallowed. | [Safety Statements ]
S22:Do not breathe dust . | [WGK Germany ]
1
| [RTECS ]
UP8050000
| [Autoignition Temperature]
336 °C | [TSCA ]
Yes | [HS Code ]
29322980 | [Safety Profile]
Poison by ingestion.
Moderately toxic by intraperitoneal route.
Questionable carcinogen with experimental
tumorigenic data. Combustible when
exposed to heat or flame. When heated to
decomposition it emits acrid smoke and
irritating fumes. | [Hazardous Substances Data]
520-45-6(Hazardous Substances Data) | [Toxicity]
LD50 orally in rats: 1000 mg/kg (Spencer) |
| Hazard Information | Back Directory | [Chemical Properties]
Dehydroacetic acid is a white to cream-coloured powder that is only very slightly soluble in water (less than 0.1 %). However, the sodium salt hydrate (CSH7Na04.H20) has a solubility of 33% in water at 25°C, and 48% in propylene glycol. The acid is 22% soluble in acetone, 18% in benzene, and I g dissolves in about 35 ml of ethanol.It is used to reduce pickle bloating, and as a pesticide and preservative for squash and strawberries. Its permissible use level is 65ppm.
Dehydroacetic acid is one of the food additives found in red wine and was determined by ultra-fast liquid chromatography-tandem quadrupole mass spectrometry (UFLC-MS/MS).
To assay dehydroacetic acid, add 500 mg to a 250-ml Erlenmeyer flask and dissolve in 75 ml of neutral alcohol. Following the addition of phenolphthalein T.S., titrate with 0.1 N NaOH to a pink end-point that persists for at least 30 s. Each ml of 0.1 N NaOH = 16.82 mg of dehydroacetic acid (National Academy of Sciences, 1963).
Dehydroacetic acid is a synthetic chemical (no plant-based preservatives that meet our efficacy standards currently exist) that is considered to be a low hazard for human health and for the environment. | [Definition]
ChEBI:Dehydroacetic acid is a pyran-2,4-dione substituted at position 3 by an acetyl group and at position 6 by a methyl group. A fungicide and bactericide it is used primarily in processed fruit and vegetables. It has a role as a fungicide, an antibacterial agent and a plasticiser. It is a pyran-2,4-dione and a ketone. | [Preparation]
1) Dehydroacetic acid is prepared from Ethyl acetoacetate by self-condensation under mildly alkaline conditions (Sodium bicarbonate). 2) by polymerization of Ketene, obtained by thermal decomposition of Acetone).
| [Synthesis Reference(s)]
The Journal of Organic Chemistry, 49, p. 5105, 1984 DOI: 10.1021/jo00200a018 | [General Description]
Dehydroacetic acid is a pyrone derivative, that is typically synthesized by the base-catalyzed dimerization of diketene. It is used as a preservative in pharmaceutical, food and cosmetic products.
Pharmaceutical secondary standards for application in quality control, provide pharma laboratories and manufacturers with a convenient and cost-effective alternative to the preparation of in-house working standards. | [Flammability and Explosibility]
Notclassified | [Solubility in organics]
soluble in most hydrocarbons, but only about 3% soluble in alcohol and about 1.5% in Propylene glycol. Being an acid, it is soluble in aqueous alkali under formation of alkali salt .
| [storage]
Store at -20°C |
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