but this method is not nearly so satisfactory as that described
in the procedure.

When only small quantities of the acid are required, the following
modified procedure is of value. One hundred grams of benzyl cyanide
are added to a mixture containing 100 cc. of water, 100 cc.
of concentrated sulfuric acid, and 100 cc. of glacial acetic acid.
After this has been heated for forty-five minutes under
a reflux condenser, the hydrolysis is practically complete.
The reaction mixture is then poured into water, and the phenylacetic
acid isolated in the usual manner.

The odor of phenylacetic acid is disagreeable and persistent.


3. Other Methods of Preparation

The standard method of preparation of phenylacetic acid is by the
hydrolysis of benzyl cyanide with either alkali[1a] or acid.[2a] The acid
hydrolysis runs by far the more smoothly and so was the only one studied.
There are numerous other ways in which phenylacetic acid has been formed,
but none of them is of practical importance for its preparation.
These methods include the following: the action of water on phenyl
ketene;[3a] the hydrolysis and subsequent oxidation of the product
between benzaldehyde and hippuric acid;[1] the reduction of mandelic
acid;[2] the reduction of benzoylformic acid with hydriodic acid
and phosphorus;[3] the hydrolysis of benzyl glyoxalidone;[4]
the fusion of atropic acid with potassium hydroxide;[5] the action
of alcoholic potash upon chlorophenylacetylene;[6] the action
of benzoyl peroxide upon phenylacetylene;[7] the alkaline hydrolysis