Crotonic acid

CAS NO.：107-93-7
Empirical Formula: C4H6O2
Molecular Weight: 86.09
MDL number: MFCD00002701
EINECS: 203-533-9
SAFETY DATA SHEET (SDS)
Update Date: 2026-06-24 18:39:39

What is Crotonic acid?

Chemical properties

White to light yellow crystalline flakes

Chemical properties

2-Butenoic acid is a crystalline compound with a pungent odor.

The Uses of Crotonic acid

trans-Crotonic acid is used in the copolymerization of crotonic acid hydrogel systems by using gamma-rays. The crosslinked copolymeric crotonic acid hydrogels release fertilizers and drugs that help to prevent environmental pollution.

Preparation

(E)-2-Butenoic acid may be formed by oxidation of crotonaldehyde, 2-butenal. If (Z)-butenoic acid is heated at 180°C, it is converted to (E)-2-butenoid acid.

Definition

ChEBI: Crotonic acid is a but-2-enoic acid with a trans- double bond at C-2. It has been isolated from Daucus carota. It has a role as a plant metabolite. It is a conjugate acid of a crotonate.

General Description

Crotonic acid undergoes esterification with butan-2-ol by following second order reaction kinetics.

Flammability and Explosibility

Not classified

Storage

Store at RT

Purification Methods

Distil the acid under reduced pressure and/or recrystallise it from pet ether (b 60-80o) or water, or by partial freezing of the melt. [Beilstein 2 IV 1498.]

Properties of Crotonic acid

Melting point:	70-72 °C (lit.)
Boiling point:	180-181 °C (lit.)
Density	1.027 g/mL at 25 °C (lit.)
vapor density	2.97 (vs air)
vapor pressure	0.19 mm Hg ( 20 °C)
refractive index	1.4228
FEMA	3908 \| (E)-2-BUTENOIC ACID
Flash point:	190 °F
storage temp.	Store below +30°C.
solubility	H2O: soluble
form	Crystalline Flakes
pka	4.69(at 25℃)
color	White to light yellow
PH	3 (10g/l, H2O, 20℃)
Odor	at 1.00 %. milky
explosive limit	15.1%, 171°F
Water Solubility	94 g/L (25 ºC)
Merck	14,2597
JECFA Number	1371
BRN	1719943
CAS DataBase Reference	107-93-7(CAS DataBase Reference)
NIST Chemistry Reference	Crotonic acid(107-93-7)
EPA Substance Registry System	2-Butenoic acid, (2E)- (107-93-7)

Safety information for Crotonic acid

Signal word	Danger
Pictogram(s)	Corrosion Corrosives GHS05
GHS Hazard Statements	H318:Serious eye damage/eye irritation
Precautionary Statement Codes	P280:Wear protective gloves/protective clothing/eye protection/face protection. P305+P351+P338:IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.