1-Phenylethanol

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.^[5]

1-Phenylethanol

Names
IUPAC name 1-Phenylethanol
Other names Styrallyl alcohol
Identifiers
CAS Number	98-85-1 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:669
ChemSpider	7131
ECHA InfoCard	100.002.461
EC Number	202-707-1
PubChem CID	7409
UNII	E6O895DQ52 Y
UN number	2937
CompTox Dashboard (EPA)	DTXSID1020859
InChI InChI=1S/C8H10O/c1-7(9)8-5-3-2-4-6-8/h2-7,9H,1H3 Key: WAPNOHKVXSQRPX-UHFFFAOYSA-N
SMILES CC(C1=CC=CC=C1)O
Properties
Chemical formula	C8H10O
Molar mass	122.167 g·mol−1
Appearance	Colourless liquid with a floral[1] or almond-like odor[2]
Melting point	20.7 °C (69.3 °F; 293.8 K)
Boiling point	204 °C (399 °F; 477 K)
Solubility in water	1.95 g dm−3[3]
log P	1.4
Hazards
Flash point	93 °C (199 °F; 366 K)[4]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

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.^[6]

Natural occurrence

1-Phenylethanol is found in nature as a glycoside, together with its hydrolase β-primeverosidase in tea (Camellia sinensis) flowers.^[7] 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.^[8]

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.^[9]

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.^[10]

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,^[11] 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.^[12]

See also

• 2-Phenylethanol, achiral isomer of 1-phenylethanol.