Trifluoromethanesulfonic anhydride → Trifluoromethanesulfonic anhydride

Participants

Reaction Steps

As it is described in Table 2 that the yield of pentafluorophenylbis(triflyl)methane is 45%, it was revealed that when pentafluorophenylbis(triflyl)methane is produced using a pentafluoromethylbromide, both of pentafluorophenylbis(triflyl)methane and 4-tert-butyl-2,3,5,6-tetrafluorophenylbis(triflyl)methane can be obtained at a ratio of 1:1 (45% yield, respectively). However, it was found out that when 1.0 equivalent weight of t-BuLi and 0.5 equivalent weight of Tf2O are used, the production of 4-tert-butyl-2,3,5,6-tetrafluorophenylbis(triflyl)methane is completely suppressed, and pentafluorophenylbis(triflyl)methane can be obtained at 95% yield with Tf2O as a base. Consequently, the reactions of pentafluorophenylbis(triflyl)methane with the various types of alkyl lithium reagents were examined, in order to determine the generality and range of the nucleophilic substitution specific to the para position of pentafluorophenylbis(triflyl)methane. Table 3 shows the types of alkyl lithium reagents, the reaction conditions and the yield of the para position substituents of pentafluorophenylbis(triflyl)methane. The para position substituents of pentafluorophenylbis(triflyl)methane shown in Table 3 are obtained by washing the reaction product obtained by reacting pentafluorophenylbis(triflyl)methane with alkyl lithium reagent, with a hydrochloric solution. The “Bn” shown in Table 3 represents a benzyl group.

Provenance & Evidence