PURPOSE: To obtain the title compound useful as an antiplogistic and analgesic in high yield, by hydrolyzing a condenszate of easily available 3-benzyl acetophenone with an α-halogeno-acetate, by decarboxylating the hydrohyzate, and by oxidizing the resulting product with a strong oxidizing agent.

CONSTITUTION: 3-Benzylacetophenone is condensed with an α-halogenoacetate under the conditions of Darzen's condensation to give a glycidate of formula I: (-COOR is esterified carboxyl group), which is hydrolyzed in the presence of an alkali, and decarboxylated in the presence of a strong acid, e.g. HCl, to form novel 2-(3-benzylphenyl)-propionaldehyde of formula II. The methylene and aldehyde groups of the aldehyde are oxidized with a strong oxidizing agent, e.g. a permanganate, to afford 2-(3-benzoylphenyl)-propionic acid of formula III.