Crotonaldehyde

Last updated
Crotonaldehyde [1]
Crotonaldehyde.png
Crotonaldehyde-3D-balls.png
Names
IUPAC name
(2E)-but-2-enal
Other names
Crotonaldehyde
Crotoinic aldehyde
β-Methacrolein
β-Methyl acrolein
2-butenal
Propylene aldehyde
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard 100.021.846 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 204-647-1
KEGG
PubChem CID
RTECS number
  • GP9499000
UNII
UN number 1143
  • InChI=1S/C4H6O/c1-2-3-4-5/h2-4H,1H3/b3-2+ Yes check.svgY
    Key: MLUCVPSAIODCQM-NSCUHMNNSA-N Yes check.svgY
  • InChI=1/C4H6O/c1-2-3-4-5/h2-4H,1H3/b3-2+
    Key: MLUCVPSAIODCQM-NSCUHMNNBQ
  • O=C/C=C/C
Properties
C4H6O
Molar mass 70.091 g·mol−1
Appearancecolourless 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]
1.4362
Hazards
GHS labelling:
GHS-pictogram-flamme.svg GHS-pictogram-acid.svg GHS-pictogram-skull.svg GHS-pictogram-exclam.svg GHS-pictogram-silhouette.svg GHS-pictogram-pollu.svg
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)
NFPA 704.svgHealth 4: Very short exposure could cause death or major residual injury. E.g. VX gasFlammability 3: Liquids and solids that can be ignited under almost all ambient temperature conditions. Flash point between 23 and 38 °C (73 and 100 °F). E.g. gasolineInstability 2: Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water. E.g. white phosphorusSpecial hazards (white): no code
4
3
2
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):
600 ppm (rat, 30 min)
1375 ppm (rat, 30 min)
519 ppm (mouse, 2 hr)
1500 ppm (rat, 30 min) [3]
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

cis-3-hexenal
(E,E)-2,4-Decadienal

Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
X mark.svgN  verify  (what is  Yes check.svgYX mark.svgN ?)

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]

Contents

Production and reactivity

Crotonaldehyde is produced by the aldol condensation of acetaldehyde:

2 CH3CHO → CH3CH=CHCHO + H2O

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]

Uses

Crotonylidene diurea is a specialty fertilizer. Crotonylidene diurea.svg
Crotonylidene diurea is a specialty fertilizer.

It is a precursor to many fine chemicals. A prominent industrial example is the crossed aldol condensation with diethyl ketone to give trimethylcyclohexenone, this can be easily converted to trimethylhydroquinone, which is a precursor to the vitamin E. [9] Other derivatives include crotonic acid, 3-methoxybutanol and the food preservative Sorbic acid. Condensation with two equivalents of urea gives a pyrimidine derivative that is employed as a controlled-release fertilizer. [4]

Safety

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]

See also

Related Research Articles

Mesitylene or 1,3,5-trimethylbenzene is a derivative of benzene with three methyl substituents positioned symmetrically around the ring. The other two isomeric trimethylbenzenes are 1,2,4-trimethylbenzene (pseudocumene) and 1,2,3-trimethylbenzene (hemimellitene). All three compounds have the formula C6H3(CH3)3, which is commonly abbreviated C6H3Me3. Mesitylene is a colorless liquid with sweet aromatic odor. It is a component of coal tar, which is its traditional source. It is a precursor to diverse fine chemicals. The mesityl group (Mes) is a substituent with the formula C6H2Me3 and is found in various other compounds.

In chemistry, a dehydration reaction is a chemical reaction that involves the loss of water from the reacting molecule or ion. Dehydration reactions are common processes, the reverse of a hydration reaction.

<span class="mw-page-title-main">Methyl isobutyl ketone</span> Chemical compound

Methyl isobutyl ketone (MIBK, 4-methylpentan-2-one) is an organic compound with the condensed chemical formula (CH3)2CHCH2C(O)CH3. This ketone is a colourless liquid that is used as a solvent for gums, resins, paints, varnishes, lacquers, and nitrocellulose.

<span class="mw-page-title-main">Dimethylamine</span> Chemical compound

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.

<span class="mw-page-title-main">Butyraldehyde</span> Chemical compound

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.

<span class="mw-page-title-main">Crotonic acid</span> Chemical compound

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. 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.

<i>o</i>-Xylene Chemical compound

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.

Chlorotoluenes are aryl chlorides based on toluene in which at least one aromatic hydrogen atom is replaced with a chlorine atom. They have the general formula C7H8–nCln, where n = 1–5 is the number of chlorine atoms.

Salicylic aldehyde (2-hydroxybenzaldehyde) is an organic compound with the formula C6H4OH(CHO). Along with 3-hydroxybenzaldehyde and 4-hydroxybenzaldehyde, it is one of the three isomers of hydroxybenzaldehyde. This colorless oily liquid has a bitter almond odor at higher concentration. Salicylaldehyde is a precursor to coumarin and a variety of chelating agents.

<span class="mw-page-title-main">Methacrylic acid</span> Chemical compound

Methacrylic acid, abbreviated MAA, is an organic compound with the formula CH2=C(CH3)CO2H. 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).

Crotyl alcohol, or crotonyl alcohol, is an unsaturated alcohol. It is a colourless liquid that is moderately soluble in water and miscible with most organic solvents. Two isomers of this alcohol exist, cis and trans.

<span class="mw-page-title-main">Pentanal</span> Chemical compound

Pentanal is the organic compound with molecular formula C4H9CHO. Classified as an alkyl aldehyde, it is a colorless volatile liquid. Its odor is described as fermented, bready, fruity, nutty, berry.

2-Cyanoguanidine is a nitrile derived from guanidine. It is a dimer of cyanamide, from which it can be prepared. 2-Cyanoguanidine is a colourless solid that is soluble in water, acetone, and alcohol, but not nonpolar organic solvents.

<span class="mw-page-title-main">Trimethyl phosphite</span> Chemical compound

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.

In organic chemistry, 3-hydroxybutanal is an organic compound with the formula CH3CH(OH)CH2CHO and the structure H3C−CH(OH)−CH2−CH=O. It is classified as an aldol and the word "aldol" can refer specifically to 3-hydroxybutanal. It is formally the product of the dimerization of acetaldehyde. A thick colorless or pale-yellow liquid, it is a versatile and valuable intermediate with diverse impacts. The compound is chiral although this aspect is not often exploited.

<span class="mw-page-title-main">Propionaldehyde</span> Chemical compound

Propionaldehyde or propanal is the organic compound with the formula CH3CH2CHO. It is the 3-carbon aldehyde. It is a colourless, flammable liquid with a pungent and fruity odour. It is produced on a large scale industrially.

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.

<span class="mw-page-title-main">Diethyl succinate</span> Chemical compound

Diethyl succinate is the diethyl ester of succinate.

<span class="mw-page-title-main">Propionyl chloride</span> Chemical compound

Propionyl chloride (also propanoyl chloride) is the organic compound with the formula CH3CH2C(O)Cl. It is the acyl chloride derivative of propionic acid. It undergoes the characteristic reactions of acyl chlorides. It is a colorless, corrosive, volatile liquid.

α,β-Unsaturated carbonyl compound Functional group of organic compounds

α,β-Unsaturated carbonyl compounds are organic compounds with the general structure (O=CR)−Cα=Cβ-R. Such compounds include enones and enals, but also carboxylic acids and the corresponding esters and amides. In these compounds, the carbonyl group is conjugated with an alkene. Unlike the case for carbonyls without a flanking alkene group, α,β-unsaturated carbonyl compounds are susceptible to attack by nucleophiles at the β-carbon. This pattern of reactivity is called vinylogous. Examples of unsaturated carbonyls are acrolein (propenal), mesityl oxide, acrylic acid, and maleic acid. Unsaturated carbonyls can be prepared in the laboratory in an aldol reaction and in the Perkin reaction.

References

  1. Merck Index , 11th Edition, 2599
  2. 1 2 3 4 5 NIOSH Pocket Guide to Chemical Hazards. "#0157". National Institute for Occupational Safety and Health (NIOSH).
  3. 1 2 "Crotonaldehyde". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
  4. 1 2 3 R. P. Schulz; J. Blumenstein; C. Kohlpaintner (2005). "Crotonaldehyde and Crotonic Acid". Ullmann's Encyclopedia of Industrial Chemistry . Weinheim: Wiley-VCH. doi:10.1002/14356007.a08_083. ISBN   978-3527306732.
  5. Longley Jr., R. I..; Emerson, W. S.; Blardinelli, A. J. (1954). "3,4-Dihydro-2-methoxy-4-methyl-2H-pyran". Org. Synth. 34: 29. doi:10.15227/orgsyn.034.0029.
  6. Coburn, E. R. (1947). "3-Penten-2-ol". Org. Synth. 27: 65. doi:10.15227/orgsyn.027.0065.
  7. "Catalysts". 8 January 2011.
  8. Dittmar, Heinrich; Drach, Manfred; Vosskamp, Ralf; Trenkel, Martin E.; Gutser, Reinhold; Steffens, Günter (2009). "Fertilizers, 2. Types". Ullmann's Encyclopedia of Industrial Chemistry . Weinheim: Wiley-VCH. doi:10.1002/14356007.n10_n01. ISBN   978-3527306732.
  9. Müller, Marc-André; Schäfer, Christian; Litta, Gilberto; Klünter, Anna-Maria; Traber, Maret G.; Wyss, Adrian; Ralla, Theo; Eggersdorfer, Manfred; Bonrath, Werner (6 December 2022). "100 Years of Vitamin E: From Discovery to Commercialization" (PDF). European Journal of Organic Chemistry. 2022 (45). doi:10.1002/ejoc.202201190.