2-Phenylethyl alcohol

Phenylethyl alcohol has a roselike odor and occurs in the volatile oils of rose, orange flowers, and others. It is an oily liquid and is much used in perfume formulation. 

Phenylethyl alcohol can be made by a number of procedures the Grignard reaction is used generally  

However, the Friedel-Crafts reaction (Fig. 1) is also employed to manufacture this particular chemical. 

Benzeneethanol benzyl carbinol benzylmethanol p-hydroxy-ethyl benzene PEA phenethanol p-phenylethyl alcohol 2-phenylethyl alcohol phenylethanol. 

Phenylethyl alcohol is used as an antimicrobial preservative in nasal, ophthalmic, and otic formulations at 0.25-0.5% v/v concentration it is generally used in combination with other preservatives.Phenylethyl alcohol has also been used on its own as an antimicrobial preservative at concentrations up to 1% v/v in topical preparations. At this concentration, mycoplasmas are inactivated within 20 minutes, although enveloped viruses are resistant. Phenylethyl alcohol is also used in flavors and as a perfumery component, especially in rose perfumes. 

Fungi poor activity against molds and fungi. 

Spores inactive, e.g., at 0.6% v/v concentration, reported to be ineffective against spores of Bacillus stearothermophilus at 100°C for 30 minutes. 

Phenylethyl alcohol is a clear, colorless liquid with an odor of rose oil. It has a burning taste that irritates and then anesthetizes mucous membranes. 

Equip a 3 litre three-necked flask with a separatory funnel, a mercury-sealed mechanical stirrer and a long reflux condenser with an inner tube 

The alcohol may be purified by conversion into the calcium chloride addition compound. Treat it with anhydrous calcium chloride much heat is evolved and the addition compound is formed. After several hours, remove any oil which has not reacted by washing with petroleum ether (b.p. 60-80°). Decompose the solid with ice water, separate the alcohol, dry and distil. 

Aromatic alcohols are insoluble in water and usually burn with a smoky flame. Their boiling points are comparatively high some are solids at the ordinary temperature. Many may be oxidised by cautious addition of dilute nitric acid to the corresponding aldehyde upon neutralis-tion of the excess of acid, the aldehyde may be isolated by ether extraction or steam distillation, and then identified as detailed under Aromatic Aldehydes, Section IV,135. 

Most aromatic alcohols exhibit the majority of the reactions given under Aliphatic Alcohols, Section 111,27, and may be converted into crystalline derivatives as there described. 

Alcohol B.P. M.P. 3 5-Dinitro-benzoate p-Nilro- benzoate Phenyl- urethane a-Naph- thyl- Hydrogen 3-nltro- Other Derivatives 

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Styrene may be conveniently prepared in the laboratory by heating p-phenylethyl alcohol (Section IV,204) with sohd sodium or potassium hydroxide when an almost quantitative dehydration occurs ... 

In a 250 ml. distilling flask (1) place 122 g. (119 ml.) of p-phenylethyl alcohol and 40 g. of sodium hydroxide peUets (or 56 g. of potassium hydroxide). Heat is evolved. Warm gently until bubbles commence to form and the mixture separates into two sharply-defined layers. Distil slowly water, etc. passes over first accompamed by the gradual dis appearance of the upper phase. FinaUy the styrene passes over at 140 160° (mainly 150°) coUect this separately in a receiver containing about 0 1 g. of hydroquinone. Dry the distillate with a httle anhydrous calcium chloride or magnesium sulphate, and then distil under reduced pressure (2). C oUect the pure styrene at 42-43°/18 mm. The 3rield is 80 g. Add about 0-2 g. of hydroquinone (anti-oxidant) if it is desired to keep the phenylethylene. 

None of the bonds to the chirality center is broken when hydroxide attacks the carbonyl group Had an 8 2 reaction occurred instead inversion of configuration at the chirality center would have taken place to give (8) (—) 1 phenylethyl alcohol... 

An oxirane process utilizes ethylbenzene to make the hydroperoxide, which then is used to make propylene oxide [75-56-9]. The hydroperoxide-producing reaction is similar to the first step of cumene LPO except that it is slower (2,224,316—318). In the epoxidation step, a-phenylethyl alcohol [98-85-1] is the coproduct. It is dehydrated to styrene [100-42-5]. The reported 1992 capacity for styrene by this route was 0.59 X 10 t/yr (319). The corresponding propylene oxide capacity is ca 0.33 x 10 t/yr. The total propylene oxide capacity based on hydroperoxide oxidation of propylene [115-07-1] (coproducts are /-butyl alcohol and styrene) is 1.05 x 10 t/yr (225). 

Organic compounds normally cause Htde or no corrosion of magnesium. Tanks or other containers of magnesium alloys are used for phenol [108-95-2] methyl bromide [74-96 ] and phenylethyl alcohol [60-12-8]. Most alcohols cause no more than mild attack, but anhydrous methanol attacks magnesium vigorously with the formation of magnesium methoxide [109-88-6]. This attack is inhibited by the addition of 1% ammonium sulfide [12135-76-1] or the presence ofwater. 

Benzyl Alcohol and p-Phenylethyl Alcohols" ia ECT 1st ed., Vol. 2, pp. 483—489, by H. L. Simons and E. E. Polger, Harold L. Simons, Inc. (Benzyl alcohol), and E. T. Theimer, van Ametingen-Haebler, Inc. (P-Phenylethyl alcohol) "Benzyl Alcohol and P-Phenylethyl Alcohol" ia ECT 2nd ed., pp. 442—449, by William E. Ringk, Benzol Products Company (Benzyl alcohol), and E. T. Theimer, International Elavors Eragrances, Inc. (P-Phenylethyl... 

It also results by reducing phenylethyl alcohol in vapour with copper dust at 250°, when hydrogen is evolved —... 

The coproduct a-phenylethyl alcohol could be dehydrated to styrene. 

CL-Phenylethanol (a-Phenylethyl alcohol, Methyl-phenyl carbinol). C6H5, CHOH.CH3, mw 122.16, liq, bp 203.6° at 475mm, d 1.019g/cc at 13/4°. Prepn and other properties are given in Beil 6,475, (236) [445]... 

Air Products, USA., has developed bis-(2-methoxy ethyl) aminosulphur trifluoride as a cost effective, safe, stable fluorinating agent, made by reaction of di-2-methylethylamine with sulphur tetrafluoride and trade named Deoxo-Fluor, which replaces the more temperamental diethylaminesulphur trifluoride. Thus, p-phenylethyl alcohol was converted to P-phenylethyl fluoride in 85% yield (Stinson, 1999). 

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