1-Phenylethanol
{{Chembox
|Reference=
|Name=1-Phenylethanol
|IUPACName=1-Phenylethanol
|OtherNames=Styrallyl alcohol
|ImageFile=Methylphenylcarbinol.svg
|ImageSize=150px
|ImageAlt=
|ImageName=
|Section1={{Chembox Identifiers
| CASNo = 98-85-1
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo_Comment =
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = E6O895DQ52
| ChEBI = 669
| PubChem = 7409
| ChemSpiderID = 7131
| StdInChI = 1S/C8H10O/c1-7(9)8-5-3-2-4-6-8/h2-7,9H,1H3
| StdInChIKey = WAPNOHKVXSQRPX-UHFFFAOYSA-N
| EINECS = 202-707-1
| SMILES = CC(C1=CC=CC=C1)O
| UNNumber = 2937
}}
|Section2={{Chembox Properties
| AtmosphericOHRateConstant =
| Appearance = Colourless liquid with a floralLewis, R.J., Sr (Ed.). Hawley's Condensed Chemical Dictionary. 12th ed. New York, NY: Van Nostrand Rheinhold Co., 1993, p. 759 or almond-like odorGerhartz, W. (exec ed.). Ullmann's Encyclopedia of Industrial Chemistry. 5th ed.Vol A1: Deerfield Beach, FL: VCH Publishers, 1985 to Present., p. VA24 488
| BoilingPtC = 204
| BoilingPt_ref =
| Density =
| C=8 | H=10 | O=1
| LogP = 1.4
| MeltingPtC = 20.7
| pKa =
| pKb =
| Solubility = 1.95 g dm−3Southworth GR, Keller JL; Water Air Soil Poll 28: 239-48 (1986)
| SolubleOther =
| Solvent = glycerol, mineral oil, alcohol, most organic solventsFenaroli's Handbook of Flavor Ingredients. Volume 2. Edited, translated, and revised by T.E. Furia and N. Bellanca. 2nd ed. Cleveland: The Chemical Rubber Co., 1975., p. 348
| VaporPressure =
}}
|Section7={{Chembox Hazards
| ExternalSDS =
| FlashPtC = 93
| FlashPt_ref = Fire Protection Guide to Hazardous Materials. 12 ed. Quincy, MA: National Fire Protection Association, 1997., p. 325-71
| LD50 =
| LC50 =
| MainHazards =
| NFPA-F =
| NFPA-H =
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| NFPA-S =
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1-Phenylethanol is the organic compound with the formula C6H5CH(OH)CH3. It is one of the most commonly available chiral alcohols. It is a colorless liquid with a mild gardenia-hyacinth scent.
Phenylethanol is an aromatic alcohol, it has the role of mouse metabolite.
It is a natural product and is found in Cichorium endivia, Castanopsis cuspidata and other organisms.{{Cite web |last=PubChem |title=1-Phenylethanol |url=https://pubchem.ncbi.nlm.nih.gov/compound/7409 |access-date=2023-09-10 |website=pubchem.ncbi.nlm.nih.gov |language=en}}
Natural occurrence
1-Phenylethanol is found in nature as a glycoside, together with its hydrolase β-primeverosidase in tea (Camellia sinensis) flowers.{{Cite journal|last=Zhou|first=Ying|last2=Dong|first2=Fang|last3=Kunimasa|first3=Aiko|last4=Zhang|first4=Yuqian|last5=Cheng|first5=Sihua|last6=Lu|first6=Jiamin|last7=Zhang|first7=Ling|last8=Murata|first8=Ariaki|last9=Mayer|first9=Frank|date=2014-08-13|title=Occurrence of glycosidically conjugated 1-phenylethanol and its hydrolase β-primeverosidase in tea (Camellia sinensis) flowers|journal=Journal of Agricultural and Food Chemistry|volume=62|issue=32|pages=8042–8050|doi=10.1021/jf5022658|issn=1520-5118|pmid=25065942}} It is also reportedly present in cranberries, grapes, chives, Scottish spearmint oil, cheeses, cognac, rum, white wine, cocoa, black tea, filbert, cloudberries, beans, mushrooms, and endives.{{Cite book|title=Fenaroli's Handbook of Flavor Ingredients, Fifth Edition|last=Burdock|first=George A.|publisher=CRC Press|year=2005}}
Synthesis
Racemic 1-phenylethanol is produced by the reduction of acetophenone by sodium borohydride. Alternatively, benzaldehyde can be reacted with methylmagnesium chloride or similar organometallic compounds to afford racemic 1-phenylethanol.
Asymmetric hydrogenation of acetophenone by Noyori catalysts proceeds quantitatively (50 atm H2, room temperature, minutes) in >99% e.e.{{cite journal |doi=10.1038/s41570-018-0049-z|title=The role of the metal-bound N–H functionality in Noyori-type molecular catalysts|year=2018|last1=Dub|first1=Pavel A.|last2=Gordon|first2=John C.|s2cid=106394152|journal=Nature Reviews Chemistry|volume=2|issue=12|pages=396–408}}
The organic oxidising agent ethylbenzene hydroperoxide yields 1-phenylethanol when reduced. Used for the epoxidation of propene, this coproduces propylene oxide, and is an important step in the PO/SM process for the production of styrene.{{cite patent
| country = US
| number = 6504038B1
| invent1 = Jacobus Johannes Van Der Sluis
| status = patent
| title = Process for the preparation of styrene and propylene oxide
| pubdate = 2003-01-07
| gdate = 2003-01-07
| fdate = 1999-07-15
| assign1 = Shell USA Inc
}}
Applications
In the final step of the PO/SM process, dehydration of 1-phenylethanol yields styrene, analogous to many other dehydrations of alcohols to yield alkenes. While secondary to the direct dehydrogenation of ethylbenzene, the PO/SM method remains industrially significant. This route accounted for approximately 15% of styrene production in the United States in 1993,{{cite report
| author = Radian Corporation
| date = 1993-04-20
| title = LOCATING AND ESTIMATING AIR EMISSIONS FROM SOURCES OF STYRENE
| url = https://www3.epa.gov/ttnchie1/le/styrene.pdf
| publisher = United States Environmental Protection Agency
| format = PDF
| page = 18
| access-date = 2024-05-06
| quote = The majority of styrene is produced by dehydrogenation of ethylbenzene, with about 15 percent produced by hydroperoxidation of ethylbenzene.
}} and has seen international development in the 21st century, especially in developing economies that have seen growth in demand for both styrene and propylene oxide.{{cite web
| title=The propylene oxide problem
| first=Rhian
| last=O'Connor
| date=2017-07-06
| publisher = ICIS Chemical Business
| website = Independent Commodity Intelligence Services
| url=https://www.icis.com/subscriber/icb/2017/07/06/10122038/the-propylene-oxide-problem/
| access-date=2024-05-06}}
See also
- 2-Phenylethanol, achiral isomer of 1-phenylethanol.