3,4,5-Trifluorobenzoic acid (CAS number 121602-93-5) is a benzoic acid derivative with three fluorine substituents at para- and meta-positions. 3,4,5-Trifluorobenzoic acid finds its application as a transient directing group in transition metal catalyzed C-H activation reactions. The fluorine electron withdrawing groups contribute the ideal acidity to the carboxylic acid while no steric hindrance group is present at the ortho-positions. 3,4,5-Trifluorobenzoic acid assists the concerted metalation deprotonation as the C-H activation step, thus facilitating the catalytic cycle.
A salt of 3,4,5-trifluorobenzoic acid improves the solubility and permeability of naftopidil in benign prostatic hyperplasia treatment. 3,4,5-Trifluorobenzoic acid is also used as a synthetic building block for dibenzoate esters type anticancer drugs.