Allyl alcohol ( IUPAC name: prop-2-en-1-ol) is an

organic compound In chemistry, organic compounds are generally any chemical compounds that contain carbon- hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. Th ...

with the structural formula . Like many

alcohol Alcohol most commonly refers to: * Alcohol (chemistry), an organic compound in which a hydroxyl group is bound to a carbon atom * Alcohol (drug), an intoxicant found in alcoholic drinks Alcohol may also refer to: Chemicals * Ethanol, one of sev ...

s, it is a water-soluble, colourless liquid. It is more toxic than typical small alcohols. Allyl alcohol is used as a raw material for the production of

glycerol Glycerol (), also called glycerine in British English and glycerin in American English, is a simple triol compound. It is a colorless, odorless, viscous liquid that is sweet-tasting and non-toxic. The glycerol backbone is found in lipids know ...

, but is also used as a precursor to many specialized compounds such as flame-resistant materials, drying oils, and

plasticizers A plasticizer ( UK: plasticiser) is a substance that is added to a material to make it softer and more flexible, to increase its plasticity, to decrease its viscosity, and/or to decrease friction during its handling in manufacture. Plasticiz ...

. Allyl alcohol is the smallest representative of the

allyl In organic chemistry, an allyl group is a substituent with the structural formula , where R is the rest of the molecule. It consists of a methylene bridge () attached to a vinyl group (). The name is derived from the scientific name for garlic, ...

Production

Allyl alcohol can be obtained by many methods. It was first prepared in 1856 by Auguste Cahours and August Hofmann by

hydrolysis Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysis ...

of allyl iodide. Today allyl alcohol is produced commercially by the Olin and Shell

corporation A corporation is an organization—usually a group of people or a company—authorized by the state to act as a single entity (a legal entity recognized by private and public law "born out of statute"; a legal person in legal context) and ...

s through the hydrolysis of allyl chloride: :CH2=CHCH2Cl + NaOH -> CH2=CHCH2OH + NaCl Allyl alcohol can also be made by the rearrangement of

propylene oxide Propylene oxide is an acutely toxic and carcinogenic organic compound with the molecular formula CH3CHCH2O. This colourless volatile liquid with an odour similar to ether, is produced on a large scale industrially. Its major application is its us ...

, a reaction that is catalyzed by potassium alum at high temperature. The advantage of this method relative to the allyl chloride route is that it does not generate salt. Also avoiding chloride-containing intermediates is the "acetoxylation" of

propylene Propylene, also known as propene, is an unsaturated organic compound with the chemical formula CH3CH=CH2. It has one double bond, and is the second simplest member of the alkene class of hydrocarbons. It is a colorless gas with a faint petrole ...

to allyl acetate: :CH2=CHCH3 + 1/2 O2 + CH3COOH -> CH2=CHCH2OCOCH3 + H2O Hydrolysis of this acetate gives allyl alcohol. In alternative fashion,

can be oxidized to

acrolein Acrolein (systematic name: propenal) is the simplest unsaturated aldehyde. It is a colorless liquid with a piercing, acrid smell. The smell of burnt fat (as when cooking oil is heated to its smoke point) is caused by glycerol in the burning fa ...

, which upon

hydrogenation Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate org ...

gives the alcohol.

Other methods

In principle, allyl alcohol can be obtained by

dehydrogenation In chemistry, dehydrogenation is a chemical reaction that involves the removal of hydrogen, usually from an organic molecule. It is the reverse of hydrogenation. Dehydrogenation is important, both as a useful reaction and a serious problem. A ...

propanol There are two isomers of propanol. * 1-Propanol, ''n''-propanol, or propan-1-ol : CH3CH2CH2OH, the most common meaning *2-Propanol, Isopropyl alcohol Isopropyl alcohol (IUPAC name propan-2-ol and also called isopropanol or 2-propanol) is a ...

. In the laboratory, it has been prepared by the reaction of

with oxalic or

formic acid Formic acid (), systematically named methanoic acid, is the simplest carboxylic acid, and has the chemical formula HCOOH and structure . It is an important intermediate in chemical synthesis and occurs naturally, most notably in some ants. Est ...

s. Allyl alcohols in general can be prepared by allylic oxidation of

compounds by selenium dioxide.

Applications

Allyl alcohol is converted mainly to glycidol, which is a chemical intermediate in the synthesis of

, glycidyl ethers, esters, and amines. Also, a variety of polymerizable esters are prepared from allyl alcohol, e.g. diallyl phthalate.

Safety

Allyl alcohol is more toxic than related alcohols. Its threshold limit value (TLV) is 2 ppm. It is a lachrymator. It is classified as an extremely hazardous substance in the United States as defined in Section 302 of the U.S.

Emergency Planning and Community Right-to-Know Act The Emergency Planning and Community Right-to-Know Act of 1986 is a United States federal law passed by the 99th United States Congress located at Title 42, Chapter 116 of the U.S. Code, concerned with emergency response preparedness. On Octo ...

(42 U.S.C. 11002), and is subject to strict reporting requirements by facilities which produce, store, or use it in significant quantities.

References

External links

* * *
State of Michigan public information on allyl alcohol

Occupational exposure guidelines
{{Authority control Primary alcohols Allyl compounds Hepatotoxins