Names | |
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IUPAC name (2E)-but-2-enal | |
Other names Crotonaldehyde Crotoinic aldehyde β-Methacrolein β-Methyl acrolein 2-butenal Propylene aldehyde | |
Identifiers | |
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3D model (JSmol) | |
ChEBI | |
ChEMBL | |
ChemSpider | |
DrugBank | |
ECHA InfoCard | 100.021.846 |
EC Number |
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KEGG | |
PubChem CID | |
RTECS number |
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UNII |
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UN number | 1143 |
CompTox Dashboard (EPA) | |
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Properties | |
C4H6O | |
Molar mass | 70.091 g·mol−1 |
Appearance | colourless liquid |
Odor | pungent, suffocating odor |
Density | 0.846 g/cm3 |
Melting point | −76.5 °C (−105.7 °F; 196.7 K) |
Boiling point | 104.0 °C (219.2 °F; 377.1 K) |
18% (20°C) [2] | |
Solubility | very soluble in ethanol, ethyl ether, acetone soluble in chloroform miscible in benzene |
Vapor pressure | 19 mmHg (20°C) [2] |
Refractive index (nD) | 1.4362 |
Hazards | |
GHS labelling: | |
Danger | |
H225, H301, H310, H311, H315, H318, H330, H335, H341, H373, H400 | |
P201, P202, P210, P233, P240, P241, P242, P243, P260, P261, P262, P264, P270, P271, P273, P280, P281, P284, P301+P310, P302+P350, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P308+P313, P310, P312, P314, P320, P321, P322, P330, P332+P313, P361, P362, P363, P370+P378, P391, P403+P233, P403+P235, P405, P501 | |
NFPA 704 (fire diamond) | |
Flash point | 13 °C (55 °F; 286 K) |
207 °C (405 °F; 480 K) | |
Explosive limits | 2.1-15.5% |
Lethal dose or concentration (LD, LC): | |
LC50 (median concentration) | 600 ppm (rat, 30 min) 1375 ppm (rat, 30 min) 519 ppm (mouse, 2 hr) 1500 ppm (rat, 30 min) [3] |
LCLo (lowest published) | 400 ppm (rat, 1 hr) [3] |
NIOSH (US health exposure limits): | |
PEL (Permissible) | TWA 2 ppm (6 mg/m3) [2] |
REL (Recommended) | TWA 2 ppm (6 mg/m3) [2] |
IDLH (Immediate danger) | 50 ppm [2] |
Related compounds | |
Related alkenals | Acrolein |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Crotonaldehyde is a chemical compound with the formula CH3CH=CHCHO. The compound is usually sold as a mixture of the E- and Z-isomers, which differ with respect to the relative position of the methyl and formyl groups. The E-isomer is more common (data given in Table is for the E-isomer). This lachrymatory liquid is moderately soluble in water and miscible in organic solvents. As an unsaturated aldehyde, crotonaldehyde is a versatile intermediate in organic synthesis. It occurs in a variety of foodstuffs, e.g. soybean oils. [4]
Crotonaldehyde is produced by the aldol condensation of acetaldehyde:
Crotonaldehyde is a multifunctional molecule that exhibits diverse reactivity. It is a prochiral dienophile. [5] It is a Michael acceptor. Addition of methylmagnesium chloride produces 3-penten-2-ol. [6]
Polyurethane catalyst N,N,N′,N′-tetramethyl-1,4-butanediamine (also known as NIAX TMBDA) was obtained by hydrogenating the reaction product of crotonaldehyde and dimethylamine. [7]
It is a precursor to fine chemicals. Sorbic acid, a food preservative, and trimethylhydroquinone, a precursor to the vitamin E, are prepared from crotonaldehyde. Other derivatives include crotonic acid and 3-methoxybutanol. It adds two equivalents of urea to give the pyrimidine derivative that is employed as a controlled-release fertilizer. [4]
Crotonaldehyde is a potent irritant even at the ppm levels. It is not very toxic, with an LD50 of 174 mg/kg (rats, oral). [4]
Allyl chloride is the organic compound with the formula CH2=CHCH2Cl. This colorless liquid is insoluble in water but soluble in common organic solvents. It is mainly converted to epichlorohydrin, used in the production of plastics. It is a chlorinated derivative of propylene. It is an alkylating agent, which makes it both useful and hazardous to handle.
Cyclohexene is a hydrocarbon with the formula C6H10. This cycloalkene is a colorless liquid with a sharp smell. It is an intermediate in various industrial processes. Cyclohexene is not very stable upon long term storage with exposure to light and air because it forms peroxides.
Methyl formate, also called methyl methanoate, is the methyl ester of formic acid. The simplest example of a carboxylate ester, it is a colorless liquid with an ethereal odour, high vapor pressure, and low surface tension. It is a precursor to many other compounds of commercial interest.
Acetic anhydride, or ethanoic anhydride, is the chemical compound with the formula (CH3CO)2O. Commonly abbreviated Ac2O, it is the simplest isolable anhydride of a carboxylic acid and is widely used as a reagent in organic synthesis. It is a colorless liquid that smells strongly of acetic acid, which is formed by its reaction with moisture in the air.
Diisopropyl ether is a secondary ether that is used as a solvent. It is a colorless liquid that is slightly soluble in water, but miscible with organic solvents. It is used as an extractant and an oxygenate gasoline additive. It is obtained industrially as a byproduct in the production of isopropanol by hydration of propylene. Diisopropyl ether is sometimes represented by the abbreviation DIPE.
Cyclohexanone is the organic compound with the formula (CH2)5CO. The molecule consists of six-carbon cyclic molecule with a ketone functional group. This colorless oily liquid has a sweet odor reminiscent of benzaldehyde. Over time, samples of cyclohexanone assume a pale yellow color. Cyclohexanone is slightly soluble in water and miscible with common organic solvents. Billions of kilograms are produced annually, mainly as a precursor to nylon.
Methyl isobutyl ketone (MIBK) is the common name for the organic compound 4-methylpentan-2-one, condensed chemical formula (CH3)2CHCH2C(O)CH3. This colourless liquid, a ketone, is used as a solvent for gums, resins, paints, varnishes, lacquers, and nitrocellulose.
Dimethylamine is an organic compound with the formula (CH3)2NH. This secondary amine is a colorless, flammable gas with an ammonia-like odor. Dimethylamine is commonly encountered commercially as a solution in water at concentrations up to around 40%. An estimated 270,000 tons were produced in 2005.
Butyraldehyde, also known as butanal, is an organic compound with the formula CH3(CH2)2CHO. This compound is the aldehyde derivative of butane. It is a colorless flammable liquid with an unpleasant smell. It is miscible with most organic solvents.
Isobutanol (IUPAC nomenclature: 2-methylpropan-1-ol) is an organic compound with the formula (CH3)2CHCH2OH (sometimes represented as i-BuOH). This colorless, flammable liquid with a characteristic smell is mainly used as a solvent either directly or as its esters. Its isomers are 1-butanol, 2-butanol, and tert-butanol, all of which are important industrially.
Crotonic acid ((2E)-but-2-enoic acid) is a short-chain unsaturated carboxylic acid, described by the formula CH3CH=CHCO2H. It is called crotonic acid because it was erroneously thought to be a saponification product of croton oil. 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.
o-Xylene (ortho-xylene) is an aromatic hydrocarbon with the formula C6H4(CH3)2, with two methyl substituents bonded to adjacent carbon atoms of a benzene ring (the ortho configuration). It is a constitutional isomer of m-xylene and p-xylene, the mixture being called xylene or xylenes. o-Xylene is a colourless slightly oily flammable liquid.
2-Chloroethanol (also called ethylene chlorohydrin or glycol chlorohydrin) is an organic chemical compound with the chemical formula HOCH2CH2Cl and the simplest beta-halohydrin (chlorohydrin). This colorless liquid has a pleasant ether-like odor. It is miscible with water. The molecule is bifunctional, consisting of both an alkyl chloride and an alcohol functional group.
Chlorotoluene is a group of three isomeric chemical compounds. They consist of a disubstituted benzene ring with one chlorine atom and one methyl group.
Methacrylic acid, abbreviated MAA, is an organic compound with the formula CH2=C(CH3)COOH. This colorless, viscous liquid is a carboxylic acid with an acrid unpleasant odor. It is soluble in warm water and miscible with most organic solvents. Methacrylic acid is produced industrially on a large scale as a precursor to its esters, especially methyl methacrylate (MMA), and to poly(methyl methacrylate) (PMMA).
Acetone cyanohydrin (ACH) is an organic compound used in the production of methyl methacrylate, the monomer of the transparent plastic polymethyl methacrylate (PMMA), also known as acrylic. It liberates hydrogen cyanide easily, so it is used as a source of such. For this reason, this cyanohydrin is also highly toxic.
4-Nitroaniline, p-nitroaniline or 1-amino-4-nitrobenzene is an organic compound with the formula C6H6N2O2. A yellow solid, it is one of three isomers of nitroaniline. It is an intermediate in the production of dyes, antioxidants, pharmaceuticals, gasoline, gum inhibitors, poultry medicines, and as a corrosion inhibitor.
Trimethyl phosphite is an organophosphorus compound with the formula P(OCH3)3, often abbreviated P(OMe)3. It is a colorless liquid with a highly pungent odor. It is the simplest phosphite ester and finds used as a ligand in organometallic chemistry and as a reagent in organic synthesis. The molecule features a pyramidal phosphorus(III) center bound to three methoxy groups.
4-Nitrotoluene or para-nitrotoluene is an organic compound with the formula CH3C6H4NO2. It is a pale yellow solid. It is one of three isomers of nitrotoluene.
2,4-Diaminotoluene is an organic compound with the formula C6H3(NH2)2CH3. It is one isomer of six with this formula. It is a white solid although commercial samples are often yellow-tan.