|Preferred IUPAC name
3D model (JSmol)
|E number||E1519 (additional chemicals)|
CompTox Dashboard (EPA)
|Molar mass||108.140 g·mol−1|
|Density||1.044 g cm−3|
|Melting point||−15.2 °C (4.6 °F; 257.9 K)|
|Boiling point||205.3 °C (401.5 °F; 478.4 K)|
|3.50 g/100 mL (20 °C) |
4.29 g/100 mL (25 °C)
|Solubility in other solvents||Soluble[vague] in benzene, methanol, chloroform, ethanol, ether, acetone|
|Vapor pressure||0.18 kPa (60 °C)|
Refractive index (nD)
Std enthalpy of
|Safety data sheet||External MSDS|
|NFPA 704 (fire diamond)|
|Flash point||93 °C (199 °F; 366 K)|
|436 °C (817 °F; 709 K)|
|Lethal dose or concentration (LD, LC):|
LD50 (median dose)
|1250 mg/kg (rat, oral)|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|what is ?)(|
Benzyl alcohol is an aromatic alcohol with the formula C6H5CH2OH. The benzyl group is often abbreviated "Bn" (not to be confused with "Bz" which is used for benzoyl), thus benzyl alcohol is denoted as BnOH. Benzyl alcohol is a colorless liquid with a mild pleasant aromatic odor. It is a useful solvent due to its polarity, low toxicity, and low vapor pressure. Benzyl alcohol has moderate solubility in water (4 g/100 mL) and is miscible in alcohols and diethyl ether. The anion produced by deprotonation of the alcohol group is known as benzylate or benzyloxide.
Benzyl alcohol is produced naturally by many plants and is commonly found in fruits and teas. It is also found in a variety of essential oils including jasmine, hyacinth and ylang-ylang. It is also found in castoreum from the castor sacs of beavers.
Benzyl alcohol is produced industrially from toluene via benzyl chloride, which is hydrolyzed:
- C6H5CH2Cl + H2O → C6H5CH2OH + HCl
For laboratory use, Grignard reaction of phenylmagnesium bromide (C6H5MgBr) with formaldehyde and the Cannizzaro reaction of benzaldehyde also give benzyl alcohol. The latter also gives benzoic acid, an example of an organic disproportionation reaction.
- C6H5CH2OH + NCCHCH2 → C6H5CH2N(H)C(O)CHCH2
Benzyl alcohol is used as a general solvent for inks, waxes, shellacs, paints, lacquers, and epoxy resin coatings. Thus it can be used in paint strippers, especially when combined with compatible viscosity enhancers to encourage the mixture to cling to painted surfaces.
It is a precursor to a variety of esters and ethers, used in the soap, perfume, and flavor industries. E.g. benzyl benzoate, benzyl salicylate, benzyl cinnamate, dibenzyl ether, benzyl butyl phthalate.
It is also used in e-liquid for e-cigarettes to enhance the flavors used. When applied to damaged skin or mucous membranes at a 10% concentration, it acts as a local anesthetic and antimicrobial agent. It can be utilized as a degreaser in rug cleaning products. As a dye solvent, it enhances the process of dying wool, nylon, and leather. It also has use as a photographic film developer and as an insect repellent.
Use in health care
Benzyl alcohol, sold under the brand name Ulesfia, was approved by the U.S. Food and Drug Administration (FDA) in 2009, as a 5% solution for the treatment of head lice in people 6 months of age and older. It affects the louse's spiracles, preventing them from closing. These then become clogged with water or mineral oil or other matter and cause the insect to die from asphyxiation.
Benzyl alcohol is used effectively for treating lice infestations as the active ingredient in lotion shampoo with 5% benzyl alcohol.
Benzyl alcohol has nearly the same refraction index as quartz and wool fiber. If a clear quartz object is immersed in benzyl alcohol, it becomes almost invisible. This test has been used to determine non-destructively whether an object is truly made of quartz. Similarly, white wool immersed in benzyl alcohol also becomes almost invisible, clearly revealing contaminants such as dark and medullated fibers and vegetable matter.
Benzyl alcohol is an ingredient used in the manufacture of soaps, topical creams, skin lotions, shampoos, and facial cleansers and is popular due to its anti-bacterial and anti-fungal properties. It is a common ingredient in a variety of household products and can cause severe allergic contact dermatitis in a significant percentage of the population.
Benzyl alcohol has low acute toxicity with an LD50 of 1.2 g/kg in rats. It oxidizes rapidly in healthy individuals to benzoic acid, conjugated with glycine in the liver, and excreted as hippuric acid. Very high concentrations can result in toxic effects including respiratory failure, vasodilation, hypotension, convulsions, and paralysis.
Benzyl alcohol is not considered to be a carcinogen, and no data are available regarding teratogenic or reproductive effects.
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