Triflic Anhydride (Tf2O)-Activated Transformation of Amides, Sulfoxides and Phosphorus Oxides via Nucleophilic Trapping

Trifluoromethanesulfonic anhydride (Tf2O) has found a wide range of applications in synthetic organic chemistry as a strong electrophilic activator leading to the transient generation of a triflate intermediate. This versatile triflate intermediate undergoes nucleophilic trapping with diverse nucleophiles to yield novel compounds. In this review, we describe the features and applications of triflic anhydride in organic synthesis reported in the past decade, especially in amide, sulfoxide, and phosphorus oxide chemistry through electrophilic activation. A plausible mechanistic pathway of each important reaction is also discussed.