chemistry

Phenethyl alcohol

Phenethyl alcohol is a chemistry topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Phenethyl alcohol rather than just read about it. In short: Phenethyl alcohol, or 2-phenylethanol, is an organic compound with the chemical formula C8H10O or C6H5(CH2)2OH. It is a colourless liquid with a pleasant floral odor.

Key takeaways

Phenethyl alcohol belongs to chemistry; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Phenethyl alcohol to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Phenethyl alcohol from memory before moving on to harder problems.

Reference excerpt

Phenethyl alcohol, or 2-phenylethanol, is an organic compound with the chemical formula C8H10O or C6H5(CH2)2OH. 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).

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.

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

C6H5MgBr + (CH2CH2)O → C6H5CH2CH2OMgBr C6H5CH2CH2OMgBr + H+ → C6H5CH2CH2OH + MgBr+ Phenethyl alcohol can also be produced by biotransformation from L-phenylalanine using immobilized yeast Saccharomyces cerevisiae. It is also possible to produce phenethyl alcohol by the reduction of phenylacetic acid using sodium borohydride and iodine in THF.

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. 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. 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. 2-phenylethanol have been investigated as potential postharvest biocontrol agents against gray mold in tomatoes, which inhibited mycelial growth and conidial germination, disrupted membrane integrity, induced reactive oxygen species accumulation and autophagy, and reduced gray mold development in tomatoes. The compound also enhanced disease-resistance enzyme activity without significantly affecting tomato fruit quality.

See also 1-Phenylethanol Congener Wine chemistry Phenethylamine

References

Illustrations

Worked examples

Example 1 — a first encounter with Phenethyl alcohol

Start with the simplest possible case. Write down what Phenethyl alcohol claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In chemistry, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Phenethyl alcohol before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Phenethyl alcohol ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Phenethyl alcohol

In research: Phenethyl alcohol appears in chemistry research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Phenethyl alcohol in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Phenethyl alcohol is common in secondary-school and first-year university syllabi. It links to neighbouring topics Flavors, Hydroxyethyl compounds, Perfume ingredients, so understanding it makes those chapters shorter.
In everyday life: Look for Phenethyl alcohol outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study Phenethyl alcohol in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Phenethyl alcohol means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Phenethyl alcohol out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Phenethyl alcohol in simple terms?

Phenethyl alcohol, or 2-phenylethanol, is an organic compound with the chemical formula C8H10O or C6H5(CH2)2OH. It is a colourless liquid with a pleasant floral odor.

Why does Phenethyl alcohol matter?

Because it connects several chemistry ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Phenethyl alcohol?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Phenethyl alcohol.