Several methods for obtaining this compoud have been described: 1) By treating the 4-isobutyl phenyl acetonitrile (I) with sodium amide and ethyl iodide, followed by the hydrolysis of the reaction product (II). 2) The reaction of the nitrile (I) with sodium ethoxide and diethyl carbonate leads to the cyanoacetic ester (III), which is treated with ethyl iodide; thus (IV) being obtained, the hydrolysis and decarboxylation of (IV) leads to the final acid. 3) The alkaline hydrolysis of the 4-isobutyl phenyl acetonitrile (I) leads to 4-isobutyl phenyl acetic acid (V). This product after treatment with Na in naphthalene and ethyl iodide (A) yields the required compound.