Crotonic Acid

Title: Crotonic Acid
CAS Registry Number: 107-93-7
CAS Name: (2E)-2-Butenoic acid
Additional Names: b-methylacrylic acid; a-crotonic acid; solid crotonic acid; trans-crotonic acid
Molecular Formula: C4H6O2
Molecular Weight: 86.09
Percent Composition: C 55.81%, H 7.02%, O 37.17%
Literature References: Has been found in clay soil in Texas; formed during the dry distillation of wood. Obtained on a commercial scale exclusively by oxygen- or air-oxidation of crotonaldehyde: Kennedy, US 2413235 (1946 to Shawinigan Chem.); Leupold, PB report 70249 (1942); Matthews, B.I.O.S. report 758 (1946). Laboratory procedure using alkaline silver oxide: Young, J. Am. Chem. Soc. 54, 2498 (1932); from acetaldehyde and malonic acid in pyridine: v. Auwers, Ann. 432, 46 (1923); Backer, Bloemen, Rec. Trav. Chim. 45, 102 (1926); Florence, Bull. Soc. Chim. Fr. [4] 41, 440 (1927); Letch, Linstead, J. Chem. Soc. 1932, 454. Toxicity study: Smyth, Carpenter, J. Ind. Hyg. Toxicol. 26, 269 (1944). Review: W. Blau et al., in Ullmann's Encyclopedia of Industrial Chemistry vol. A8 (VCH, Weinheim, 5th ed., 1987) pp 83-89.
Properties: Monoclinic needles, prisms from water or ligroin. Corrosive and combustible solid. d415 1.018; d480 0.964. mp 71.6°. bp10 80.0°; bp20 93.0°; bp40 107.8°; bp60 116.7°; bp100 128.0°; bp200 146.0°; bp400 165.5°; bp760 185.0°. nD80 1.4228. pKa (25°) 4.817. Heat of combustion: 2.00 MJ/mol. Heat of fusion: 150.9 J/g. Soly in water (g/l) at 0°: 41.5; at 10°: 54.6; at 20°: 76.1; at 25°: 94; at 30°: 122; at 40°: 656. Soly in ethanol at 25°: 52.5% w/w; acetone: 53.0% w/w; toluene: 37.5% w/w. LD50 orally in rats: 1.0 g/kg (Smyth, Carpenter).
Melting point: mp 71.6°
Boiling point: bp10 80.0°; bp20 93.0°; bp40 107.8°; bp60 116.7°; bp100 128.0°; bp200 146.0°; bp400 165.5°; bp760 185.0°
pKa: pKa (25°) 4.817
Index of refraction: nD80 1.4228
Density: d415 1.018; d480 0.964
Toxicity data: LD50 orally in rats: 1.0 g/kg (Smyth, Carpenter)
Derivative Type: Methyl ester
Molecular Formula: C5H8O2
Molecular Weight: 100.12
Percent Composition: C 59.98%, H 8.05%, O 31.96%
Properties: Liq, bp 121°; d420 0.9444; nD20 1.4242.
Boiling point: bp 121°
Index of refraction: nD20 1.4242
Density: d420 0.9444
Derivative Type: Ethyl ester
Molecular Formula: C6H10O2
Molecular Weight: 114.14
Percent Composition: C 63.14%, H 8.83%, O 28.03%
Properties: Liq, bp 138°; d420 0.9175; nD20 1.4245.
Boiling point: bp 138°
Index of refraction: nD20 1.4245
Density: d420 0.9175
Derivative Type: Vinyl ester
Molecular Formula: C6H8O2
Molecular Weight: 112.13
Percent Composition: C 64.27%, H 7.19%, O 28.54%
Properties: Liq, bp 133°; d420 0.9410; nD20 1.450.
Boiling point: bp 133°
Index of refraction: nD20 1.450
Density: d420 0.9410
Use: In the manuf of copolymers with vinyl acetate used in lacquers and paper sizing; in the manuf of softening agents for synthetic rubber. In medicinal chemistry, e.g., in the manuf of DL-threonine, vitamin A.
Crotoxin Crotoxyphos Crotyl Alcohol CRP Crufomate

Crotonic acid
Skeletal formula
Ball-and-stick model
Identifiers
CAS number 107-93-7 N
PubChem 637090
ChemSpider 552744 YesY
DrugBank DB02074
ChEBI CHEBI:41131 YesY
ChEMBL CHEMBL1213528 YesY
Jmol-3D images Image 1
Image 2
Properties
Molecular formula C4H6O2
Molar mass 86.09 g/mol
Density 1.02 g/cm3
Melting point 70–73 °C
Boiling point 185–189 °C
Acidity (pKa) 4.69 [1]
Hazards
MSDS SIRI.org
Related compounds
Other anions crotonate
Related carboxylic acids propionic acid
acrylic acid
butyric acid
succinic acid
malic acid
tartaric acid
fumaric acid
pentanoic acid
Related compounds butanol
butyraldehyde
crotonaldehyde
2-butanone
 N (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Crotonic acid, or trans-2-butenoic acid, is a short-chain unsaturated carboxylic acid, described by the formula CH3CH=CHCO2H. Crotonic acid is so named because it was erroneously thought to be a saponification product of croton oil. It crystallizes as needles from hot water.

Racemic threonine can be prepared from crotonic acid by alpha-functionalization using mercury(II) acetate.[2]