Isobutyric acid

"Valerianic acid" redirects here. Not to be confused with Valerenic acid or Valeric acid.
Isobutyric acid[1]
Skeletal formula of isobutyric acid
Ball-and-stick model of the isobutyric acid molecule
Names
Preferred IUPAC name
2-Methylpropanoic acid[2]
Other names
Isobutyric acid
2-Methylpropionic acid
Isobutanoic acid
Identifiers
3D model (JSmol)
3DMet
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard 100.001.087 Edit this at Wikidata
EC Number
  • 201-195-7
KEGG
RTECS number
  • NQ4375000
UNII
UN number 2529
  • InChI=1S/C4H8O2/c1-3(2)4(5)6/h3H,1-2H3,(H,5,6) checkY
    Key: KQNPFQTWMSNSAP-UHFFFAOYSA-N checkY
  • InChI=1/C4H8O2/c1-3(2)4(5)6/h3H,1-2H3,(H,5,6)
    Key: KQNPFQTWMSNSAP-UHFFFAOYAB
  • O=C(O)C(C)C
Properties
C4H8O2
Molar mass 88.11 g/mol
Density 0.9697 g/cm3 (0 °C)
Melting point −47 °C (−53 °F; 226 K)
Boiling point 155 °C (311 °F; 428 K)
Acidity (pKa) 4.86[3]
-56.06x10−6 cm3/mol
Hazards[4][5]
GHS labelling:
GHS02: FlammableGHS05: CorrosiveGHS06: Toxic
Danger
H226, H302, H311, H314
P210, P280, P301+P312+P330, P303+P361+P353, P305+P351+P338+P310
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 2: Must be moderately heated or exposed to relatively high ambient temperature before ignition can occur. Flash point between 38 and 93 °C (100 and 200 °F). E.g. diesel fuelInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
3
2
0
Flash point 55 °C (131 °F; 328 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Isobutyric acid, also known as 2-methylpropanoic acid or isobutanoic acid, is a carboxylic acid with structural formula (CH3)2CHCOOH. It is an isomer of butyric acid. It is classified as a short-chain fatty acid. Deprotonation or esterification gives derivatives called isobutyrates.

Isobutyric acid is a colorless liquid with a somewhat unpleasant odor. It is soluble in water and organic solvents. It is found naturally in carobs (Ceratonia siliqua), in vanilla, and in the root of Arnica dulcis, and as an ethyl ester in croton oil.[6]

  1. ^ Merck Index, 11th Edition, 5039
  2. ^ "Front Matter". Nomenclature of Organic Chemistry : IUPAC Recommendations and Preferred Names 2013 (Blue Book). Cambridge: The Royal Society of Chemistry. 2014. p. 748. doi:10.1039/9781849733069-FP001. ISBN 978-0-85404-182-4.
  3. ^ Bjerrum, J.; et al. (1958). Stability Constants. London: Chemical Society.
  4. ^ Sigma-Aldrich. "Isobutyric acid". Retrieved 2020-10-03.
  5. ^ "NFPA Hazard Classification". Retrieved 2020-10-03.
  6. ^ Chisholm, Hugh, ed. (1911). "Butyric Acid" . Encyclopædia Britannica. Vol. 4 (11th ed.). Cambridge University Press. p. 892.