4-Methylsulfonylphenylacetic acid is a key pharmaceutical intermediate, notably used in the synthesis of etoricoxib (a COX-2 inhibitor). This compound exhibits a melting point of 136-140°C (lit.) and boiling point of 443.0±37.0°C at 760 mmHg. With a density of 1.35 g/cm³ and refractive index of 1.600 (estimate), it demonstrates moderate solubility in DMSO and methanol (when heated). The material should be stored sealed in dry conditions at room temperature. Safety precautions include wearing protective equipment due to potential irritant properties (GHS Category 2). Its unique structure combining phenylacetic acid and methylsulfonyl groups makes it valuable for designing NSAIDs and other bioactive molecules.
