Benzyl alcohol
Template:Chembox new Benzyl alcohol is an organic compound with the formula C6H5CH2OH. The benzyl group is commonly abbreviated "Bn", thus BnOH, for benzyl alcohol. Benzyl alcohol is a colorless liquid with a mild pleasant aromatic odor. It is a natural constituent of a variety of essential oils including jasmine, hyacinth, and ylang-ylang.[1] Benzyl alcohol is also a useful solvent due to its polarity, low toxicity, and low vapor pressure.
Benzyl alcohol is partially soluble in water (4 g/100 mL) and completely miscible in alcohols and ether. It is prepared by the hydrolysis of benzyl chloride using sodium hydroxide:
It can also be prepared via a Grignard reaction by reacting phenylmagnesium bromide (C6H5MgBr) with formaldehyde, followed by acidification. Like most alcohols, it reacts with carboxylic acids to form esters
Applications
Benzyl alcohol is used as a general solvent for inks, paints, lacquers, and epoxy resin coatings.[2] It is also a precursor to a variety of esters, used in the soap, perfume, and flavor industries, as well as for pharmaceuticals. It exhibits bacteriostatic and antipruritic properties. It is also used as a photographic developer.
Illustrative organic synthetic uses
In organic synthesis, benzyl esters are popular protecting groups because they can be removed by mild hydrogenolysis.[3]
BnOH reacts with acrylonitrile to give N-benzylacrylamide. This is an example of a Ritter reaction:[4]
- C6H5CH2OH + NCCHCH2 → C6H5CH2N(H)C(O)CHCH2
Nanotechnological uses
Benzyl alcohol has been used as a dielectric solvent for the dielectrophoretic reconfiguration of nanowires.[5]
Health & safety
Benzyl alcohol is used as a bacteriostatic preservative in parenteral (IV) medications. Benzyl alcohol is also known for its toxic effects including respiratory failure, vasodilation, hypotension, convulsions, and paralysis. Sixteen Neonatal deaths have been associated with the use of benzyl alcohol as a preservative in saline flush solutions.[6] Preservative free solutions are now being used for the infant population.[citation needed]
Benzyl alcohol should be avoided by people with perfume allergy.[citation needed]
References
- ↑ Merck Index, 11th Edition, 1138.
- ↑ Benzyl alcohol at chemicalland21.com
- ↑ Template:OrgSynth
- ↑ Template:OrgSynth
- ↑ Alexander Wissner-Gross (19 Oct 2006). "Nanowires get reconfigured". Nanotechweb.org.
- ↑ "Neonatal Deaths Associated With Use Of Benzyl Alcohol — United States". Morbidity and Mortality Weekly Report. 31 (22): 290–1. 11 Jun 1982.