Bromobenzene → Triphenylsulfonium Tetrafluoroborate

Participants

Reaction Conditions

Reaction Steps

To a suspension of magnesium turning (12 g) in ethyl ether (500 ml), bromobenzene (83.5 g, 0.54 mole) was added dropwise under reflux with stirring and continued to stir for 1 hour under reflux. to this Grignard reagent, benzene (500 ml) was added and concentrated until 500 ml. To this resultant mixture, a solution of diphenylsulfoxide (30 g, 0.15 mole) in benzene (200 ml) was added and reacted with stirring for 40 hours under reflux. After the reaction mixture was cooled to 0° C., 40% tetrafluoroboric acid (50 ml) was added dropwise at 0°-5° C. and reacted with stirring for 5 hours at the same temperature. After standing at room temperature overnight, the aqueous layer separated was extracted with methylene chloride (100 ml×3), the organic layer was washed with H2O, dried over anhydrous sodium sulfate and dried. The residual crude solid was recrystallized from chloroform/ethyl ether to give 28 g of triphenylsulfonium tetrafluoroborate as white crystals. m.p. 291°-292° C.

Provenance & Evidence