Industrially, benzyl chloride is
precursor to benzyl esters, which are used as
plasticizers, flavorants, and
perfumes.
Quaternary ammonium salts, such as the
benzalkonium chlorides used as
surfactants, are produced by alkylation of
tertiary amines with benzyl chloride.
indoles and
amines, and
carbanions and
enolates.
Cyanide displaces chloride from benzyl chloride. The resulting
benzyl cyanide is a precursor to
phenylacetic acid, a precursor to pharmaceuticals and commercial fragrances. Phenols and alcohols are common oxygen-containing substrates, the product being
benzyl ethers. In
organic synthesis, these ethers serve as
protecting groups. Debenzylation of such ethers can be achieved by
hydrogenolysis using
palladium on carbon. : Benzyl chloride undergoes
hydrolysis to form
benzyl alcohol: : When treated with aqueous sodium hydroxide, benzyl chloride converts to
benzyl alcohol and
dibenzyl ether, depending on conditions. Benzyl chloride also reacts readily with
magnesium to produce a
Grignard reagent. It is preferable over
benzyl bromide for the preparation of this reagent, since the reaction of the bromide with magnesium tends to form the
Wurtz coupling product
1,2-diphenylethane. Benzyl chloride is used to install benzyl groups on aromatic substrates. For example, when benzyl chloride is treated with benzene and
aluminium trichloride under the conditions of
Friedel-Crafts alkylation, it gives
diphenylmethane. Heating benzyl chloride in the presence of aluminium trichloride gives
poly(p-phenylene methylene): :{{chem2|n C6H5CH2Cl -> (C6H4CH2)_{
n} + n HCl}} ==Safety and regulations==