CF3SO2F

CF3SO2F, also known as trifluoromethylsulfonyl fluoride, is an organofluorine compound featuring a sulfonyl fluoride group (SO2F) attached to a trifluoromethyl group. Its formula is CF3SO2F. The molecule is a reactive, volatile reagent used in organic synthesis. It is moisture-sensitive and hydrolyzes readily in the presence of water to give triflic acid (CF3SO3H) and hydrogen fluoride (HF).

Its utility stems from two main aspects: as an electrophilic source of the trifluoromethyl group for carbon–carbon bond formation, and as a donor of the triflate moiety for sulfonate ester formation. In particular, CF3SO2F can convert alcohols into corresponding triflate esters (OTf derivatives) under mild conditions, enabling downstream transformations. It also serves as a versatile building block in SuFEx (sulfur(VI) fluoride exchange) click chemistry, reacting with nucleophiles such as amines, alcohols, and thiols to form sulfonamide, sulfonate, and related linkages under catalysis or base activation.

Synthesis and handling of CF3SO2F are conducted under controlled conditions from suitable precursors, typically involving fluorosulfonyl transfer steps. It is handled in gas or compressed-liquid form within dry, well-ventilated facilities and in the absence of moisture. Safety: it is corrosive and an irritant; hydrolysis releases HF and triflic acid, so appropriate personal protective equipment and a fume hood are required.

See also: sulfuryl fluoride, sulfonyl fluoride, SuFEx.