2-Fluoro-5-(methylthio)benzoic acid is an aromatic carboxylic acid bearing a fluorine atom ortho to the acid function and a lipophilic methylthio group at the meta-position. The compound is odourless to faintly sulfurous, air-stable, and readily soluble in common organic solvents (ethanol, methanol, ethyl acetate, dichloromethane) while only sparingly soluble in cold water.
Key physical data:
Melting point: 168–170 °C
Predicted b.p.: 356 °C (760 mmHg)
Density: 1.42 g cm⁻³ (predicted)
Predicted pKa (carboxylic): 3.7
Predicted log P: 2.6
Typical uses:
Key intermediate for the synthesis of benzothiazine-1,1-dioxide COX-2 inhibitors after oxidation of the thio-ether to sulfone.
Starting material for 2-fluoro-5-methylsulfonylbenzoyl chloride, a key scaffold for herbicidal ALS-inhibitors.
Ligand precursor for Pd-catalysed C–H activation chemistry exploiting the ortho-directing effect of the carboxylic acid.
Quality specification (custom grade):
Purity (HPLC): ≥97 %
Water content (KF): ≤0.3 %
Residue on ignition: ≤0.1 %
Heavy metals: ≤20 ppm
Hazard statement:
Causes skin and eye irritation (R36/37/38). Avoid inhalation of dust; use gloves, goggles and adequate ventilation. SDS available on request.
