To an anhydrous dichloromethane (69 mL) solution of difluoromethyl phenyl sulfide (3.98 g, 25 mmol) was added solid m-chloroperoxybenzoic acid (m-CPBA, 15.9 g, 92.0 mmol) in batches at 0 °C. The reaction mixture was gradually warmed to room temperature and stirred overnight. Upon completion of the reaction, dichloromethane (50 mL) was added to dilute the mixture, and the mixture was washed sequentially with 10% aqueous sodium sulfite (2 × 100 mL), 5% aqueous sodium bicarbonate (4 × 50 mL) and saturated saline (2 × 100 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography with dichloromethane and hexane (3:1, v/v) as eluents. Thin layer chromatography (TLC) showed an Rf value of 0.40 (dichloromethane/hexane, 3:1). 4.24 g of difluoromethyl phenyl sulfone was finally obtained in 88% (22.1 mmol) yield. The structure of the product was confirmed by nuclear magnetic resonance hydrogen (1H NMR, 300 MHz, CDCl3), carbon (13C NMR, 101 MHz, CDCl3) and fluorine (19F NMR, 282 MHz, CDCl3) spectra, and the data were in agreement with the literature reports.