Chemistry:1-Octanol

From HandWiki

1-Octanol, also known as octan-1-ol, is the organic compound with the molecular formula CH3(CH2)7OH. It is a fatty alcohol. Many other isomers are also known generically as octanols. 1-Octanol is manufactured for the synthesis of esters for use in perfumes and flavorings. It has a pungent odor. Esters of octanol, such as octyl acetate, occur as components of essential oils[1] (grapefruit oil, orange oil, bergamot oil, mandarin oil and lime oil[2]). It is used to evaluate the lipophilicity of pharmaceutical products.

Preparation

Octanol is mainly produced industrially by the oligomerization of ethylene using triethylaluminium followed by oxidation of the alkylaluminium products. This route is known as the Ziegler alcohol synthesis.[1] An idealized synthesis is shown:

Al(C2H5)3 + 9 C2H4 → Al(C8H17)3
Al(C8H17)3 + 3 O + 3 H2O → 3 HOC8H17 + Al(OH)3

The process generates a range of alcohols, which can be separated by distillation.

The Kuraray process defines an alternative route to 1-octanol, but using C4 + C4 building strategy. 1,3-Butadiene is dimerized concomitant with the addition of one molecule of water. This conversion is catalyzed by palladium complexes. The resulting doubly unsaturated alcohol is then hydrogenated.[3]

Water/octanol partitioning

Main article: Physics:Octanol-water partition coefficient

Octanol and water are immiscible. The distribution of a compound between water and octanol is used to calculate the partition coefficient, P, of that molecule (often expressed as its logarithm to the base 10, log P). Water/octanol partitioning is a relatively good approximation of the partitioning between the cytosol and lipid membranes of living systems.[4]

Many dermal absorption models consider the stratum corneum/ water partition coefficient to be well approximated by a function of the water/octanol partition coefficient of the form:[5]

log⁡(Ksc/w)=a+blog⁡(Kw/o)

Where a and b are constants, Ksc/w is the stratum corneum/water partition coefficient, and Kw/o is the water/octanol partition coefficient. The values of a and b vary between papers, but Cleek & Bunge[6] have reported the values a = 0, b = 0.74.

Properties and uses

With a flash point of 81 °C, 1-octanol is not seriously flammable, though its autoignition temperature is as low as 245 °C. 1-Octanol is mainly consumed as a precursor to perfumes.[1] 1-Octanol hydrogen bonds to Lewis bases. It is a Lewis acid in the ECW model and its acid parameters are EA = 0.85 and C A = 0.87.[7]

Octanol has a sedative and anesthetic effect in animal studies, though 1-octanol may not be the most potent isomer.[8][9][10][11][12][13] 1-Octanol has been examined for controlling essential tremor and other types of involuntary neurological tremors because evidence indicates it can relieve tremor symptoms at lower doses than are required to obtain a similar level of symptomatic relief from consumption of ethanol, thereby reducing the risk of alcohol intoxication at therapeutic dosages.[14][15]

See also

References

  1. ↑ 1.0 1.1 1.2 Falbe, Jürgen; Bahrmann, Helmut; Lipps, Wolfgang; Mayer, Dieter; Frey, Guido D. (2013). "Alcohols, Aliphatic" (in en). Ullmann's Encyclopedia of Industrial Chemistry (American Cancer Society). doi:10.1002/14356007.a01_279.pub2. ISBN 978-3527306732. 
  2. ↑ "Эфирные масла цитрусовых и их химический состав". https://citrusmasla.ru/. 
  3. ↑ J. Grub; E. Löser (2012). "Ullmann's Encyclopedia of Industrial Chemistry". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a04_431.pub2. 
  4. ↑ Schwarzenbach, Rene P.; Gschwend, Philip M.; Imboden, Dieter M. (2003). Environmental organic chemistry. John Wiley. ISBN 0-471-35053-2. 
  5. ↑ McCarley KD, Bunge AL (2001). "Pharmacokinetic Models of Dermal Absorption". Journal of Pharmaceutical Sciences 90 (11): 1699–1719. doi:10.1002/jps.1120. PMID 11745728. 
  6. ↑ Cleek RL, Bunge AL (1993). "A new method for estimating dermal absorption from chemical exposure. 1. General approach". Pharmaceutical Research 10 (4): 497–506. doi:10.1023/A:1018981515480. PMID 8483831. 
  7. ↑ Vogel, Glenn C.; Drago, Russell S. (1996). "The ECW Model" (in en). Journal of Chemical Education 73 (8): 701. doi:10.1021/ed073p701. ISSN 0021-9584. Bibcode: 1996JChEd..73..701V. https://pubs.acs.org/doi/abs/10.1021/ed073p701. 
  8. ↑ "A relationship between alcohol intoxication and the disordering of brain membranes by a series of short-chain alcohols". The Journal of Pharmacology and Experimental Therapeutics 218 (3): 669–675. September 1981. PMID 7264950. 
  9. ↑ "Lipid solubility of sedative-hypnotic drugs influences hypothermic and hypnotic responses of long-sleep and short-sleep mice". The Journal of Pharmacology and Experimental Therapeutics 263 (1): 232–240. October 1992. PMID 1403788. 
  10. ↑ "Alcohol modulation of cloned GABAA receptor-channel complex expressed in human kidney cell lines". Brain Research 631 (1): 143–146. December 1993. doi:10.1016/0006-8993(93)91200-c. PMID 7507787. 
  11. ↑ "Pharmacological properties of T-type Ca2+ current in adult rat sensory neurons: effects of anticonvulsant and anesthetic agents". Journal of Neurophysiology 79 (1): 240–252. January 1998. doi:10.1152/jn.1998.79.1.240. PMID 9425195. 
  12. ↑ "Channel gating of the glycine receptor changes accessibility to residues implicated in receptor potentiation by alcohols and anesthetics". The Journal of Biological Chemistry 279 (32): 33919–33927. August 2004. doi:10.1074/jbc.M313941200. PMID 15169788. 
  13. ↑ "Numerous classes of general anesthetics inhibit etomidate binding to gamma-aminobutyric acid type A (GABAA) receptors". The Journal of Biological Chemistry 285 (12): 8615–8620. March 2010. doi:10.1074/jbc.M109.074708. PMID 20083606. 
  14. ↑ "Pilot trial of 1-octanol in essential tremor". Neurology 62 (1): 122–124. January 2004. doi:10.1212/01.wnl.0000101722.95137.19. PMID 14718713. 
  15. ↑ "An open-label, single-dose, crossover study of the pharmacokinetics and metabolism of two oral formulations of 1-octanol in patients with essential tremor". Neurotherapeutics 8 (4): 753–762. October 2011. doi:10.1007/s13311-011-0045-1. PMID 21594724. 



Retrieved from "https://handwiki.org/wiki/index.php?title=Chemistry:1-Octanol&oldid=4246487"