Crotonic acid

Crotonic acid
Skeletal formula of crotonic acid
Ball-and-stick model of the crotonic acid molecule
Names
Preferred IUPAC name
(2E)-But-2-enoic acid
Other names
(E)-But-2-enoic acid
(E)-2-Butenoic acid
Crotonic acid
trans-2-Butenoic acid
β-Methylacrylic acid
3-Methylacrylic acid
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard 100.003.213 Edit this at Wikidata
UNII
  • InChI=1S/C4H6O2/c1-2-3-4(5)6/h2-3H,1H3,(H,5,6)/b3-2+ checkY
    Key: LDHQCZJRKDOVOX-NSCUHMNNSA-N checkY
  • InChI=1/C4H6O2/c1-2-3-4(5)6/h2-3H,1H3,(H,5,6)/b3-2+
    Key: LDHQCZJRKDOVOX-NSCUHMNNBH
  • C/C=C/C(O)=O
  • O=C(O)/C=C/C
Properties
C4H6O2
Molar mass 86.090 g·mol−1
Density 1.02 g/cm3
Melting point 70 to 73 °C (158 to 163 °F; 343 to 346 K)
Boiling point 185 to 189 °C (365 to 372 °F; 458 to 462 K)
Acidity (pKa) 4.69 [1]
Hazards
Safety data sheet (SDS) SIRI.org
Related compounds
Other anions
 crotonate
propionic acid
acrylic acid
butyric acid
succinic acid
malic acid
tartaric acid
fumaric acid
pentanoic acid
tetrolic acid
Related compounds
 butanol
butyraldehyde
crotonaldehyde
2-butanone
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)

Crotonic acid ((2E)-but-2-enoic acid) is a short-chain unsaturated carboxylic acid described by the formula CH3CH=CHCO2H. The name crotonic acid was given because it was erroneously thought to be a saponification product of croton oil.[2] It crystallizes as colorless needles from hot water. With a cis-alkene, Isocrotonic acid is an isomer of crotonic acid. Crotonic acid is soluble in water and many organic solvents. Its odor is similar to that of butyric acid.

  1. ^ Dawson, R. M. C.; et al. (1959). Data for Biochemical Research. Oxford: Clarendon Press.
  2. ^ Chisholm, Hugh, ed. (1911). "Crotonic Acid" . Encyclopædia Britannica. Vol. 7 (11th ed.). Cambridge University Press. p. 511.