DifluoroiodoMethyl phenyl sulfone

1535-65-5

802919-90-0

Difluoromethyl phenyl sulfone (192 mg, 1 mmol) and elemental iodine (508 mg, 4 mmol) were dissolved in DMF (4 mL) in a Schlenk flask under argon protection. The system was cooled to -30 °C and a solution of t-BuOK (448 mg, 4 mmol) in DMF (4 mL) was added slowly dropwise via syringe. The reaction temperature was maintained between -30 °C and -20 °C with continuous stirring for 1 h. The reaction progress was monitored by 19F NMR tracking. Upon completion of the reaction, the reaction was quenched by the addition of 1N HCl aqueous solution (5 mL) at -50 °C, followed by slow warming to room temperature. Saturated aqueous NaCl solution (10 mL) was added and the reaction mixture was extracted with ether (15 mL x 3). The organic phases were combined, dried with anhydrous MgSO4, filtered and concentrated under reduced pressure to remove the solvent. The residue was purified by silica gel column chromatography (eluent: hexane/ethyl acetate=9:1) to afford the target product difluoroiodomethyl phenyl sulfone (294 mg, 92% yield), which is a colorless solid and turns red easily when exposed to light. The product characterization data were as follows: 1H NMR (500 MHz, CDCl3): δ 7.63 (t, J = 7.4 Hz, 2H), 7.79 (t, J = 7.4 Hz, 1H), 7.99 (d, J = 7.5 Hz, 2H); 13C NMR (125 MHz, CDCl3): δ 102.5 (t, J = 355 Hz), 128.1, 129.7, 131.3, 136.1; 19F NMR (470 MHz, CDCl3): δ -52.2; MS (EI, m/z): 318 (M+), 177, 142, 127; HRMS (EI): m/z calcd for C7H5F2IO2S (M+) 317.9023, found 317.9013. found 317.9013.