In a typical experiment, phenyl sulfoxide (10 mmol) was added to a solution of N02BF4 (12 mmol) in nitromethane, and the mixture was heated under reflux for 2-3 h. Usual workup of the reaction mixture gave a 78% yield of diphenyl sulfone (5f). The reaction can also be carried out at ambient temperature, in which case, however, a longer reaction time is required for the completion of the reaction. The progress of the reaction was easily ...
