Phenylacetic acid

Phenylacetic acid (abr. PAA and synonyms are: α-toluic acid, benzeneacetic acid, alpha tolylic acid, 2-phenylacetic acid) is an organic compound containing a phenyl functional group and an acetic acid functional group. It is a white solid with a disagreeable odor. Because it is used in the illicit production of phenylacetone, it is subject to controls in the United States.

Significance
Phenylacetic acid has been found to be an active auxin (a type of plant hormone) molecule, predominantly found in fruits. However its effect is much weaker than the effect of the basic auxin molecule indole-3-acetic acid.

Phenylacetic acid is used in some perfumes, possessing a honey-like odour in low concentrations, and is also used in penicillin G production.

Its refractive index is 1.5025.