In organic chemistry, the triflyl group (systematic name: trifluoromethanesulfonyl group) is a functional group with the formula R−SO2CF3 and structure R−S(=O)2−CF3. The triflyl group is often represented by –Tf.
The related triflate group (trifluoromethanesulfonate) has the formula R−OSO2CF3, and is represented by –OTf.[1]