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.[3] It is used to evaluate the lipophilicity of pharmaceutical products.
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| Names | |
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| Preferred IUPAC name
Octan-1-ol | |
| Other names
1-Octanol; n-Octanol; Capryl alcohol; Octyl alcohol
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| Identifiers | |
3D model (JSmol)
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| 1697461 | |
| ChEBI | |
| ChEMBL | |
| ChemSpider | |
| ECHA InfoCard | 100.003.561 |
| EC Number |
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| 82528 | |
| KEGG | |
PubChem CID
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| UNII | |
CompTox Dashboard (EPA)
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| Properties | |
| C8H18O | |
| Molar mass | 130.231 g·mol−1 |
| Appearance | Colorless liquid[1] |
| Odor | Aromatic[1] |
| Density | 0.83 g/cm3 (20 °C)[1] |
| Melting point | −16 °C (3 °F; 257 K)[1] |
| Boiling point | 195 °C (383 °F; 468 K)[1] |
| 0.3 g/L (20 °C)[1] | |
| Viscosity | 7.36 cP[2] |
| Hazards | |
| GHS labelling: | |
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| Warning | |
| H319 | |
| P264, P280, P305+P351+P338, P337+P313 | |
| NFPA 704 (fire diamond) | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Preparation
editOctanol 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.[3] 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.[4]
Water/octanol partitioning
editOctanol 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.[5]
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:[6]
Where a and b are constants, is the stratum corneum/water partition coefficient, and is the water/octanol partition coefficient. The values of a and b vary between papers, but Cleek & Bunge[7] have reported the values a = 0, b = 0.74.
Properties and uses
editWith 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.[3] It 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 alcohol intoxication at therapeutic dosages.[8]
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.[9]
See also
editReferences
edit- ^ a b c d e f Record in the GESTIS Substance Database of the Institute for Occupational Safety and Health
- ^ Bhattacharjee, A.; Roy, M. N. (2010-11-17). "Density, Viscosity, and Speed of Sound of (1-Octanol + 2-Methoxyethanol),(1-Octanol + N,N-Dimethylacetamide), and (1-Octanol + Acetophenone) at Temperatures of (298.15, 308.15, and 318.15) K". Journal of Chemical & Engineering Data. 55 (12): 5914–5920. doi:10.1021/je100170v.
- ^ a b c Falbe, Jürgen; Bahrmann, Helmut; Lipps, Wolfgang; Mayer, Dieter; Frey, Guido D. (2013). "Alcohols, Aliphatic". Ullmann's Encyclopedia of Industrial Chemistry. American Cancer Society. doi:10.1002/14356007.a01_279.pub2. ISBN 978-3527306732.
- ^ J. Grub; E. Löser (2012). "Butadiene". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a04_431.pub2. ISBN 978-3527306732.
- ^ Schwarzenbach, Rene P.; Gschwend, Philip M.; Imboden, Dieter M. (2003). Environmental organic chemistry. John Wiley. ISBN 0-471-35053-2.
- ^ 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.
- ^ 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. S2CID 24534572.
- ^ Bushara K.; et al. (2004). "Pilot trial of 1-octanol in essential tremor". Neurology. 62 (1): 122–124. doi:10.1212/01.wnl.0000101722.95137.19. PMID 14718713. S2CID 9015641.
- ^ Vogel, Glenn C.; Drago, Russell S. (1996). "The ECW Model". Journal of Chemical Education. 73 (8): 701. Bibcode:1996JChEd..73..701V. doi:10.1021/ed073p701. ISSN 0021-9584.