Citral

Chemical compound From Wikipedia, the free encyclopedia

Citral is an acyclic monoterpene aldehyde. Being a monoterpene, it is made of two isoprene units. Citral is a collective term which covers two geometric isomers that have their own separate names; the E-isomer is named geranial (trans-citral; α-citral[2]) or citral A. The Z-isomer is named neral (cis-citral; β-citral[2]) or citral B. These stereoisomers occur as a mixture, often not in equal proportions; e.g. in essential oil of Australian ginger, the neral to geranial ratio is 0.61.[3]

Quick facts Names, Identifiers ...
Citral[1]
Skeletal formula of geranial
Geranial
Ball-and-stick model of the geranial molecule
Skeletal formula of neral
Neral
Ball-and-stick model of the neral molecule
Names
IUPAC name
3,7-dimethylocta-2,6-dienal
Other names
citral
geranialdehyde
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.023.994 Edit this at Wikidata
EC Number
  • 226-394-6
KEGG
RTECS number
  • RG5075000
UNII
UN number 2810
  • InChI=1S/C10H16O/c1-9(2)5-4-6-10(3)7-8-11/h5,7-8H,4,6H2,1-3H3/b10-7+ checkY
    Key: WTEVQBCEXWBHNA-JXMROGBWSA-N checkY
  • InChI=1/C10H16O/c1-9(2)5-4-6-10(3)7-8-11/h5,7-8H,4,6H2,1-3H3/b10-7+
    Key: WTEVQBCEXWBHNA-JXMROGBWBB
  • O=CC=C(C)CCC=C(C)C
  • O=C/C=C(/CC/C=C(/C)C)C
Properties
C10H16O
Molar mass 152.24 g/mol
Appearance Pale yellow liquid
Odor Lemon like
Density 0.893 g/cm3
Boiling point 229 °C (444 °F; 502 K)
Vapor pressure 0.22 mmHg (20 °C)
−98.9×10−6 cm3/mol
Hazards
GHS labelling:
GHS07: Exclamation mark
Warning
H315, H317
P261, P264, P272, P280, P302+P352, P321, P332+P313, P333+P313, P362, P363, P501
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 0: Exposure under fire conditions would offer no hazard beyond that of ordinary combustible material. E.g. sodium chlorideFlammability 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g. canola oilInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
0
1
0
Flash point 91 °C (196 °F; 364 K)
Related compounds
Related alkenals
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)
Close

Natural Occurrence

Citral is present in the volatile oils of several plants:[4][5][6]

Of the many sources of citral, the Australian tree Backhousia citriodora (family Myrtaceae) is considered superior.[7]

Uses

Citral is a precursor in the industrial production of vitamin A, vitamin E, vitamin K.

Citral is also precursor to lycopene, ionone and methylionone.

Fragrances

Citral has a strong lemon (citrus) scent and is used as an aroma compound in perfumery. It is used to fortify lemon oil. (Nerol, another perfumery compound, has a less intense but sweeter lemon note.) The aldehydes citronellal and citral are considered key components responsible for the lemon note with citral preferred.[7]

It also has pheromonal effects in acari and insects.[8][9]

The herb Cymbopogon citratus has shown promising insecticidal and antifungal activity against storage pests.[10]

Food additive

Citral is commonly used as a food additive ingredient.[11]

It has been tested (2016) in vitro against the food-borne pathogen Cronobacter sakazakii.[12]

See also

References

External links

Related Articles

Wikiwand AI