Crotonaldehyde

Crotonaldehyde[1]
Skeletal formula of crotonaldehyde
Ball-and-stick model of (Z)-crotonaldehyde
Names
IUPAC name
(2E)-but-2-enal
Other names
Crotonaldehyde
Crotoinic aldehyde
β-Methacrolein
β-Methyl acrolein
2-butenal
Propylene aldehyde
Identifiers
  • 4170-30-3 (E/Z) checkY
  • 123-73-9 (E) checkY
  • 15798-64-8 (Z) checkY
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard 100.021.846 Edit this at Wikidata
EC Number
  • 204-647-1
KEGG
RTECS number
  • GP9499000
UNII
UN number 1143
  • InChI=1S/C4H6O/c1-2-3-4-5/h2-4H,1H3/b3-2+ checkY
    Key: MLUCVPSAIODCQM-NSCUHMNNSA-N checkY
  • 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
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]
1.4362
Hazards
GHS pictograms GHS02: FlammableGHS05: CorrosiveGHS06: ToxicGHS07: HarmfulGHS08: Health hazardGHS09: Environmental hazard
GHS Signal word 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+310, P302+350, P302+352, P303+361+353, P304+340, P305+351+338, P308+313
NFPA 704 (fire diamond)
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).
☒N verify (what is checkY☒N ?)
Infobox references

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]

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.[8]

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]

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[]

References[]

  1. ^ Merck Index, 11th Edition, 2599
  2. ^ a b c d e NIOSH Pocket Guide to Chemical Hazards. "#0157". National Institute for Occupational Safety and Health (NIOSH).
  3. ^ a b "Crotonaldehyde". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
  4. ^ a b c 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.CS1 maint: uses authors parameter (link)
  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. ^ https://jadedman.wordpress.com/2011/01/08/catalysts/
  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.

External links[]