Geraniol

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Geraniol[1]
Geraniol
Geraniol-3D-balls-B.png
Names
IUPAC name
(2E)-3,7-Dimethyl-2,6-octadien-1-ol
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.003.071
EC Number 203-377-1
UNII
Properties
C10H18O
Molar mass 154.25 g·mol−1
Density 0.889 g/cm3
Melting point −15 °C (5 °F; 258 K)[2]
Boiling point 230 °C (446 °F; 503 K)[2]
686 mg/L (20 °C)[2]
log P 3.28[3]
Hazards
NFPA 704
Flammability code 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g., canola oilHealth code 0: Exposure under fire conditions would offer no hazard beyond that of ordinary combustible material. E.g., sodium chlorideReactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogenSpecial hazards (white): no codeNFPA 704 four-colored diamond
1
0
0
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Geraniol is a monoterpenoid and an alcohol. It is the primary component of rose oil, palmarosa oil, and citronella oil (Java type). It is a colorless oil, although commercial samples can appear yellow. It has low solubility in water, but it is soluble in common organic solvents. The functional group derived from geraniol (in essence, geraniol lacking the terminal −OH) is called geranyl.

Uses and occurrence[edit]

In addition to rose oil, palmarosa oil, and citronella oil, it also occurs in small quantities in geranium, lemon, and many other essential oils. With a rose-like scent, it is commonly used in perfumes. It is used in flavors such as peach, raspberry, grapefruit, red apple, plum, lime, orange, lemon, watermelon, pineapple, and blueberry.

Geraniol is produced by the scent glands of honeybees to mark nectar-bearing flowers and locate the entrances to their hives.[4] It has been considered as a mosquito repellent.[5][6]

It is a byproduct of the metabolism of sorbate and, thus, is a very unpleasant contaminant of wine if bacteria are allowed to grow in it.

Biochemistry[edit]

Geraniol is important in biosynthesis of other terpenes. For example, myrcene and ocimene are formed by dehydration and isomerization of geraniol.[7]

Reactions[edit]

In acidic solutions, geraniol is converted to the cyclic terpene α-terpineol. The alcohol group undergoes expected reactions. It can be converted to the chloride with thionyl chloride.[8] It can be hydrogenated.[9] It can be oxidized to the aldehyde geranial.[10]

Health and safety[edit]

Geraniol is classified as D2B (Toxic materials causing other effects) using the Workplace Hazardous Materials Information System (WHMIS).[11]

Related compounds[edit]

See also[edit]

References[edit]

  1. ^ "Geraniol". The Merck Index (12th ed.). 
  2. ^ a b c Record in the GESTIS Substance Database of the Institute for Occupational Safety and Health
  3. ^ "Geraniol_msds". 
  4. ^ Danka, R. G.; Williams, J. L.; Rinderer, T. E. (1990). "A bait station for survey and detection of honey bees". Apidologie. 21 (4): 287–292. doi:10.1051/apido:19900403. 
  5. ^ Barnard, D. R.; Xue, R. (2004). "Laboratory evaluation of mosquito repellents against Aedes albopictus, Culex nigripalpus, and Ochlerotatus triseriatus (Diptera: Culicidae)". Journal of Medical Entomology. 41 (4): 726–730. doi:10.1603/0022-2585-41.4.726. PMID 15311467. 
  6. ^ "UF entomologist develops safe, effective alternative to DEET insect repellents". University of Florida. 1999. 
  7. ^ Eggersdorfer, M. (2005), "Terpenes", Ullmann's Encyclopedia of Industrial Chemistry, Weinheim: Wiley-VCH, doi:10.1002/14356007.a26_205 
  8. ^ Stork, Gilbert; Grieco,, Paul A.; Gregson, Michael (1974). "Allylic Chlorides from Allylic Alcohols: Geranyl Chloride". Organic Syntheses. 54: 68. doi:10.15227/orgsyn.054.0068. ; Collective Volume, 6, p. 638 
  9. ^ Takaya, Hidemasa; Ohta, Tetsuo; Inoue, Shin-ichi; Tokunaga, Makoto; Kitamura, Masato; Noyori, Ryoji (1995). "Asymmetric Hydrogenation of Allylic Alcohols Using Binap-Ruthenium Complexes: (S)-(−)-citronellol". Organic Syntheses. 72: 74. doi:10.15227/orgsyn.072.0074. ; Collective Volume, 9, p. 169 
  10. ^ Piancatelli, Giovanni; Leonelli, Francesca (2006). "Oxidation Of Nerol To Neral With Iodosobenzene and TEMPO". Organic Syntheses. 83: 18. doi:10.15227/orgsyn.083.0018. 
  11. ^ "MSDS – Geraniol". Sigma-Aldrich. Retrieved June 24, 2014. 

External links[edit]