Anisole

Anisole

Anisole or methoxybenzene is an organic compound with the formula CH3OC6H5. It is a colorless liquid with a smell reminiscent of anise seed, and in fact many of its derivatives are found in natural and artificial fragrances. The compound is mainly made synthetically and is a precursor to other synthetic compounds. It is relatively nontoxic, but is less dense than water and will float on the surface. When heated to decomposition it emits acrid smoke and irritating fumes.

Chemical properties

Anisole undergoes electrophilic aromatic substitution reaction more quickly than does benzene, which in turn reacts more quickly than nitrobenzene. The methoxy group is an ortho/para directing group, which means that electrophilic substitution preferentially occurs at these three sites. The enhanced reactivity is due to the lone pairs of electrons on the oxygen atom of the methoxy group making the ring more nucleophilic.

Production

Anisole is prepared industrially by alkylation of phenol with dimethyl ether in the presence of acid catalysts, such as BF3 or HF.

Uses

Anisole is used as a solvent, in organic synthesis, and in perfumes and fragrances. It is also used as a pesticide and a flavoring agent.

Safety

Anisole is relatively nontoxic with an LD50 of 3700 mg/kg in rats. Its main hazard is its flammability.

See also

• Methoxy group
• Ether
• Phenol