Caproic acid

Caproic acid
Names
IUPAC name
Hexanoic acid
Preferred IUPAC name
Hexanoic acid
Other names
Hexoic acid
Hexylic acid
Butylacetic acid
Pentylformic acid
1-Pentanecarboxylic acid
C6:0 (Lipid numbers)
Identifiers
3D model (JSmol)
773837
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.005.046
EC Number
  • 205-550-7
185066
KEGG
UNII
  • InChI=1S/C6H12O2/c1-2-3-4-5-6(7)8/h2-5H2,1H3,(H,7,8) Y
    Key: FUZZWVXGSFPDMH-UHFFFAOYSA-N Y
  • InChI=1/C6H12O2/c1-2-3-4-5-6(7)8/h2-5H2,1H3,(H,7,8)
    Key: FUZZWVXGSFPDMH-UHFFFAOYAY
  • CCCCCC(=O)O
Properties
C6H12O2
Molar mass 116.160 g·mol−1
Appearance Oily liquid[1]
Odor goat-like
Density 0.929 g/cm3[2]
Melting point −3.4 °C (25.9 °F; 269.8 K)[1]
Boiling point 205.8 °C (402.4 °F; 478.9 K)[1]
1.082 g/100 mL[1]
Solubility soluble in ethanol, ether
Acidity (pKa) 4.88
−78.55·10−6 cm3/mol
1.4170
Viscosity 3.1 mP
Hazards
GHS labelling:
Danger
H314
P260, P264, P280, P301+P330+P331, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P310, P312, P321, P322, P361, P363, P405, P501
NFPA 704 (fire diamond)
3
1
0
Flash point 103 °C (217 °F; 376 K)[2]
380 °C (716 °F; 653 K)
Explosive limits 1.3-9.3%
Lethal dose or concentration (LD, LC):
3000 mg/kg (rat, oral)
Related compounds
Related compounds
Pentanoic acid, Heptanoic acid
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y verify (what is YN ?)
Infobox references

Caproic acid, also known as hexanoic acid, is the carboxylic acid derived from hexane with the chemical formula CH3(CH2)4COOH. It is a colorless oily liquid with a fatty, cheesy, waxy odor resembling that of goats[1] or other barnyard animals. It is a fatty acid found naturally in various animal fats and oils, and is one of the chemicals that gives the decomposing fleshy seed coat of the ginkgo its characteristic unpleasant odor.[3] It is also one of the components of vanilla and cheese. Salts and esters of caproic acid are known as caproates or hexanoates.

Two other acids are named after goats: caprylic acid (C8) and capric acid (C10). Along with caproic acid, they account for 15% of the fat in goat's milk.

Caproic, caprylic, and capric acids (capric is a crystal- or wax-like substance, whereas the other two are mobile liquids) are used for the formation of esters, and also commonly used "neat" in: butter, milk, cream, strawberry, bread, beer, nut, and other flavors.

Properties

Caproic acid is a 6-Carbon saturated fatty acid. It occurs in a white crystalline solid form or a colorless to pale yellow liquid state, accompanied by a strong and unpleasant odor. It has limited solubility in water, although it is soluble in dimethyl ether, benzene and other organic solvents.[4][5]

It may be prepared by fractionation of the volatile fatty acids of coconut oil.[6] Caproic acid belongs to the family of medium chain fatty acids (MCFAs) which can be used to synthesize Medium-chain triglycerides.

Uses

The primary use of caproic acid is in the manufacture of its esters for use as artificial flavors, and in the manufacture of hexyl derivatives, such as hexylphenols.[1] Several progestin medications are caproate esters, such as hydroxyprogesterone caproate and gestonorone caproate. Its derivatives are also used in soaps, shampoos, conditioners and gels.

Caproic acid is also used as a component in varnish driers, as well as a lubricant. Its derivatives can also be incorporated to modify the elasticity, strength, and resilience of rubber products.[7]

DHEA-caproate ester (#121) has a IC50 of 0.049nM for the 5-alpha-reductase enzyme.[8][9]

See also

References

  1. ^ a b c d e f The Merck Index: An Encyclopedia of Chemicals, Drugs, and Biologicals (11th ed.). Merck. 1989. ISBN 091191028X.
  2. ^ a b Record in the GESTIS Substance Database of the Institute for Occupational Safety and Health
  3. ^ "Ginkgo.html". Archived from the original on 2008-12-26. Retrieved 2007-03-08.
  4. ^ "What is Caproic Acid? Cosmetic usage, alternatives, and regulatory insights". Slate. Retrieved 2026-01-07.
  5. ^ PubChem. "Hexanoic Acid". pubchem.ncbi.nlm.nih.gov. Retrieved 2026-01-07.
  6. ^ "Hexanoic acid | 142-62-1". amp.chemicalbook.com. Retrieved 2026-01-07.
  7. ^ "Industrial Applications of Hexanoic Acid (CAS 142-62-1)". www.nbinno.com. Retrieved 2026-01-07.
  8. ^ Salvador, Jorge A.R.; Pinto, Rui M.A.; Silvestre, Samuel M. . (2013). Steroidal 5α-reductase and 17α-hydroxylase/17,20-lyase (CYP17) inhibitors useful in the treatment of prostatic diseases. The Journal of Steroid Biochemistry and Molecular Biology, 137(), 199–222. doi:10.1016/j.jsbmb.2013.04.006
  9. ^ Yazmín Arellano; Eugene Bratoeff; Mariana Garrido; Juan Soriano; Yvonne Heuze; Marisa Cabeza. (2011). New ester derivatives of dehydroepiandrosterone as 5α-reductase inhibitors. , 76(12), 0–1246. doi:10.1016/j.steroids.2011.05.015