Tetramethylammonium hydroxide → Tetramethylammonium pentafluorobenzenesulfonate

Participants

Reaction Steps

In 20 ml of acetic anhydride was dissolved 4.51 g (0.01 mol) of dipheny-4-phenylthiophenyllsulfonium bromide obtained in the above-described (1), and 1.07 g (0.005 mol) of potassium iodate was added thereto at 0° C. Then a mixed acid consisted of 2.5 g (0.025 mol) of concentrated sulfuric acid and 3.0 g of acetic anhydride was added dropwise at 0 to 3° C. for 1 hour, followed by gradually warming to room temperature and reacting for 9 hours with stirring. After completion of the reaction, the reaction solution was poured into 200 ml of ice water to obtain a treatment solution for formation of iodonium salt. Then, 8.0 g (0.03 mol) of pentafluorobenzenesulphonyl chloride was dissolved in 60 ml of methanol, and 44.0 g (0.072 mol) of an aqueous solution of 15% tetramethylammonium hydroxide was added dropwise thereto at 25 to 35° C. for 30 minutes and reacting at 50° C. for 1 hour with stirring. After completion of the reaction, the reaction solution was concentrated under reduced pressure, and was poured into 40 ml of water to dissolve to obtain an aqueous solution of tetramethylammonium pentafluorobenzenesulfonate. The aqueous solution and 200 ml of dichloromethane were poured into the above-described treatment solution for formation of iodonium salt, followed by reacting at room temperature for 1 hour with stirring. After completion of the reaction, the solution was fractionated, and 200 ml of water was poured into the resulting dichloromethane layer, then sodium hydrocarbonate was added thereto until the solution became neutral, followed by fractionating again. The obtained dichloromethane layer was washed with 200 ml of water and concentrated and evaporated to dryness under reduced pressure, followed by purifying the resulting crude product by a column chromatography to obtain 3.54 g (Yield: 44%) of bis{4-[4-(diphenylsulfonio)phenylthio]phenyl}iodonium tris(pentafluorobenzenesulfonate) as a pale brown glassy substance.

Provenance & Evidence