Phenethyl alcohol

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Phenethyl alcohol [1]
Phenethyl alcohol.png
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Names
IUPAC name
2-Phenylethanol
Other names
2-Phenylethanol
Phenethyl alcohol
Benzyl carbinol
β-Hydroxyethylbenzene
Benzeneethanol
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard 100.000.415 OOjs UI icon edit-ltr-progressive.svg
KEGG
PubChem CID
UNII
  • InChI=1S/C8H10O/c9-7-6-8-4-2-1-3-5-8/h1-5,9H,6-7H2 Yes check.svgY
    Key: WRMNZCZEMHIOCP-UHFFFAOYSA-N Yes check.svgY
  • InChI=1S/C8H10O/c9-7-6-8-4-2-1-3-5-8/h1-5,9H,6-7H2
  • InChI=1S/C8H10O/c9-7-6-8-4-2-1-3-5-8/h1-5,9H,6-7H2
    Key: WRMNZCZEMHIOCP-UHFFFAOYSA-N
  • c1ccc(cc1)CCO
Properties
C8H10O
Molar mass 122.167 g·mol−1
Odor Soft, like roses
Density 1.017 g/cm3
Melting point −27 °C (−17 °F; 246 K)
Boiling point 219 to 221 °C (426 to 430 °F; 492 to 494 K)
log P 1.36 [2]
Hazards
NFPA 704 (fire diamond)
NFPA 704.svgHealth 1: Exposure would cause irritation but only minor residual injury. E.g. turpentineFlammability 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
1
1
0
Safety data sheet (SDS) JT Baker MSDS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Yes check.svgY  verify  (what is  Yes check.svgYX mark.svgN ?)

Phenethyl alcohol, or 2-phenylethanol, is an organic compound with the chemical formula C6H5CH2CH2OH. It is a colourless liquid with a pleasant floral odor. It occurs widely in nature, being found in a variety of essential oils. It is slightly soluble in water (2 ml per 100 ml of H2O), but miscible with most organic solvents. The molecule of phenethyl alcohol consists of a phenethyl group (C6H5CH2CH2) attached to a hydroxyl group (−OH).

Contents

Synthesis

Phenethyl alcohol is prepared commercially via two routes. Most common is the Friedel-Crafts reaction between benzene and ethylene oxide in the presence of aluminium trichloride.

C6H6 + CH2CH2O + AlCl3 → C6H5CH2CH2OAlCl2 + HCl

The reaction affords the aluminium alkoxide that is subsequently hydrolyzed to the desired product. The main side product is diphenylethane, which can be avoided by use of excess benzene. Hydrogenation of styrene oxide also affords phenethyl alcohol. [3]

Laboratory methods

Phenethyl alcohol can also be prepared by the reaction between phenylmagnesium bromide and ethylene oxide:

C6H5MgBr + CH2CH2O → C6H5CH2CH2OMgBr
C6H5CH2CH2OMgBr + H+ → C6H5CH2CH2OH + MgBr+

Phenethyl alcohol can also be produced by biotransformation from L-phenylalanine using immobilized yeast Saccharomyces cerevisiae . [4] It is also possible to produce phenethyl alcohol by the reduction of phenylacetic acid using sodium borohydride and iodine in THF. [5]

Occurrence and uses

Phenethyl alcohol is found in extract of rose, carnation, hyacinth, Aleppo pine, orange blossom, ylang-ylang, geranium, neroli, and champaca. It is also an autoantibiotic produced by the fungus Candida albicans . [6]

Fusel alcohols like phenethyl alcohol are grain fermentation byproducts, and therefore trace amounts of phenethyl alcohol are present in many alcoholic beverages.

It is therefore a common ingredient in flavors and perfumery, particularly when the odor of rose is desired. [3] It is used as an additive in cigarettes. It is also used as a preservative in soaps due to its stability in basic conditions. It is of interest due to its antimicrobial properties.

See also

Related Research Articles

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In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two organyl groups. They have the general formula R−O−R′, where R and R′ represent organyl groups. Ethers can again be classified into two varieties: if the organyl groups are the same on both sides of the oxygen atom, then it is a simple or symmetrical ether, whereas if they are different, the ethers are called mixed or unsymmetrical ethers. A typical example of the first group is the solvent and anaesthetic diethyl ether, commonly referred to simply as "ether". Ethers are common in organic chemistry and even more prevalent in biochemistry, as they are common linkages in carbohydrates and lignin.

<span class="mw-page-title-main">Ester</span> Compound derived from an acid

In chemistry, an ester is a compound derived from an acid in which the hydrogen atom (H) of at least one acidic hydroxyl group of that acid is replaced by an organyl group. Analogues derived from oxygen replaced by other chalcogens belong to the ester category as well. According to some authors, organyl derivatives of acidic hydrogen of other acids are esters as well, but not according to the IUPAC.

<span class="mw-page-title-main">Yeast</span> Informal group of fungi

Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are estimated to constitute 1% of all described fungal species.

<span class="mw-page-title-main">Phenyl group</span> Cyclic chemical group (–C₆H₅)

In organic chemistry, the phenyl group, or phenyl ring, is a cyclic group of atoms with the formula C6H5, and is often represented by the symbol Ph. The phenyl group is closely related to benzene and can be viewed as a benzene ring, minus a hydrogen, which may be replaced by some other element or compound to serve as a functional group. A phenyl group has six carbon atoms bonded together in a hexagonal planar ring, five of which are bonded to individual hydrogen atoms, with the remaining carbon bonded to a substituent. Phenyl groups are commonplace in organic chemistry. Although often depicted with alternating double and single bonds, the phenyl group is chemically aromatic and has equal bond lengths between carbon atoms in the ring.

Acetaldehyde (IUPAC systematic name ethanal) is an organic chemical compound with the formula CH3 CHO, sometimes abbreviated as MeCHO. It is a colorless liquid or gas, boiling near room temperature. It is one of the most important aldehydes, occurring widely in nature and being produced on a large scale in industry. Acetaldehyde occurs naturally in coffee, bread, and ripe fruit, and is produced by plants. It is also produced by the partial oxidation of ethanol by the liver enzyme alcohol dehydrogenase and is a contributing cause of hangover after alcohol consumption. Pathways of exposure include air, water, land, or groundwater, as well as drink and smoke. Consumption of disulfiram inhibits acetaldehyde dehydrogenase, the enzyme responsible for the metabolism of acetaldehyde, thereby causing it to build up in the body.

<span class="mw-page-title-main">Ethylene oxide</span> Cyclic compound (C2H4O)

Ethylene oxide is an organic compound with the formula C2H4O. It is a cyclic ether and the simplest epoxide: a three-membered ring consisting of one oxygen atom and two carbon atoms. Ethylene oxide is a colorless and flammable gas with a faintly sweet odor. Because it is a strained ring, ethylene oxide easily participates in a number of addition reactions that result in ring-opening. Ethylene oxide is isomeric with acetaldehyde and with vinyl alcohol. Ethylene oxide is industrially produced by oxidation of ethylene in the presence of a silver catalyst.

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<span class="mw-page-title-main">Alkylation</span> Transfer of an alkyl group from one molecule to another

Alkylation is a chemical reaction that entails transfer of an alkyl group. The alkyl group may be transferred as an alkyl carbocation, a free radical, a carbanion, or a carbene. Alkylating agents are reagents for effecting alkylation. Alkyl groups can also be removed in a process known as dealkylation. Alkylating agents are often classified according to their nucleophilic or electrophilic character. In oil refining contexts, alkylation refers to a particular alkylation of isobutane with olefins. For upgrading of petroleum, alkylation produces a premium blending stock for gasoline. In medicine, alkylation of DNA is used in chemotherapy to damage the DNA of cancer cells. Alkylation is accomplished with the class of drugs called alkylating antineoplastic agents.

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Ethylbenzene is an organic compound with the formula C6H5CH2CH3. It is a highly flammable, colorless liquid with an odor similar to that of gasoline. This monocyclic aromatic hydrocarbon is important in the petrochemical industry as a reaction intermediate in the production of styrene, the precursor to polystyrene, a common plastic material. In 2012, more than 99% of ethylbenzene produced was consumed in the production of styrene.

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<i>tert</i>-Butyl alcohol Chemical compound

tert-Butyl alcohol is the simplest tertiary alcohol, with a formula of (CH3)3COH (sometimes represented as t-BuOH). Its isomers are 1-butanol, isobutanol, and butan-2-ol. tert-Butyl alcohol is a colorless solid, which melts near room temperature and has a camphor-like odor. It is miscible with water, ethanol and diethyl ether.

<span class="mw-page-title-main">Allyl alcohol</span> Organic compound (CH2=CHCH2OH)

Allyl alcohol is an organic compound with the structural formula CH2=CHCH2OH. Like many alcohols, it is a water-soluble, colourless liquid. It is more toxic than typical small alcohols. Allyl alcohol is used as a precursor to many specialized compounds such as flame-resistant materials, drying oils, and plasticizers. Allyl alcohol is the smallest representative of the allylic alcohols.

<span class="mw-page-title-main">Farnesol</span> Chemical compound

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<span class="mw-page-title-main">Oct-1-en-3-one</span> Chemical compound

Oct-1-en-3-one (CH2=CHC(=O)(CH2)4CH3), also known as 1-octen-3-one or amyl vinyl ketone, is the odorant that is responsible for the typical "metallic" smell of metals and blood coming into contact with skin. Oct-1-en-3-one has a strong metallic mushroom-like odor with an odor detection threshold of 0.03–1.12 µg/m3 and it is the main compound responsible for the "smell of metal", followed by decanal (smell: orange skin, flowery) and nonanal (smell: tallowy, fruity). Oct-1-en-3-one is the degradative reduction product of the chemical reaction of skin lipid peroxides and Fe2+. Skin lipid peroxides are formed from skin lipid by oxidation, either enzymatically by lipoxygenases or by air oxygen. Oct-1-en-3-one is a ketone analog of the alkene 1-octene.

The enzyme glycerol-1-phosphatase (EC 3.1.3.21) catalyzes the reaction

<span class="mw-page-title-main">Phenylacetaldehyde</span> Chemical compound

Phenylacetaldehyde is an organic compound used in the synthesis of fragrances and polymers. Phenylacetaldehyde is an aldehyde that consists of acetaldehyde bearing a phenyl substituent; the parent member of the phenylacetaldehyde class of compounds. It has a role as a human metabolite, a Saccharomyces cerevisiae metabolite, an Escherichia coli metabolite and a mouse metabolite. It is an alpha-CH2-containing aldehyde and a member of phenylacetaldehydes.

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<span class="mw-page-title-main">C-5 sterol desaturase</span> Class of enzymes

C-5 sterol desaturase is an enzyme that is highly conserved among eukaryotes and catalyzes the dehydrogenation of a C-5(6) bond in a sterol intermediate compound as a step in the biosynthesis of major sterols. The precise structure of the enzyme's substrate varies by species. For example, the human C-5 sterol desaturase oxidizes lathosterol, while its ortholog ERG3 in the yeast Saccharomyces cerevisiae oxidizes episterol.

References

  1. Merck Index (11th ed.). p. 7185.
  2. "Phenylethyl alcohol_msds".
  3. 1 2 Fahlbusch, Karl-Georg; Hammerschmidt, Franz-Josef; Panten, Johannes; Pickenhagen, Wilhelm; Schatkowski, Dietmar; Bauer, Kurt; Garbe, Dorothea; Surburg, Horst (2003). "Flavors and Fragrances". Ullmann's Encyclopedia of Industrial Chemistry. doi:10.1002/14356007.a11_141. ISBN   978-3-527-30673-2.
  4. Eshkol N, Sendovski M, Bahalul M, Katz-Ezov T, Kashi Y, Fishman A (2009). "Production of 2-phenylethanol from L-phenylalanine by a stress tolerant Saccharomyces cerevisiae strain". Journal of Applied Microbiology. 106 (2): 534–542. doi: 10.1111/j.1365-2672.2008.04023.x . PMID   19200319.
  5. Kanth JV, Periasamy M (1991). "Selective Reduction of Carboxylic Acids into Alcohols Using NaBH and I2". Journal of Organic Chemistry. 56: 5964–5965. doi:10.1021/jo00020a052.
  6. Lingappa, BT; Prasad, M; Lingappa, Y; Hunt, DF; Biemann, K (1969). "Phenethyl alcohol and tryptophol: Autoantibiotics produced by the fungus Candida albicans". Science. 163 (3863): 192–4. Bibcode:1969Sci...163..192L. doi:10.1126/science.163.3863.192. PMID   5762768. S2CID   12430791.