Trifluoromethanesulfonic anhydride

Trifluoromethanesulfonic anhydride

Identifiers
CAS Number	358-23-6 Y
3D model (JSmol)	Interactive image
ChemSpider	61068
ECHA InfoCard	100.006.016
PubChem CID	67749
InChI InChI=1S/C2F6O5S2/c3-1(4,5)14(9,10)13-15(11,12)2(6,7)8 Key: WJKHJLXJJJATHN-UHFFFAOYSA-N
SMILES C(F)(F)(F)S(=O)(=O)OS(=O)(=O)C(F)(F)F
Properties
Chemical formula	C2F6O5S2
Molar mass	282.13 g·mol−1
Density	1.6770 g/mL
Boiling point	82 °C (180 °F; 355 K)
Hazards
Safety data sheet	Fisher MSDS
R-phrases (outdated)	R14 R34
S-phrases (outdated)	S25 S26 S36/37/39 S45
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Triflic anhydride is the chemical compound with the formula (CF₃SO₂)₂O. This compound is a particularly strong electrophile, useful for introducing the triflyl group, CF₃SO₂. Abbreviated Tf₂O, triflic anhydride is the acid anhydride of the strong acid triflic acid, CF₃SO₂OH.

It can be assayed by ¹⁹F NMR spectroscopy: −72.6 ppm vs. −77.3 for TfOH (std CFCl₃).

In a representative application, is used to convert an imine into a NTf group.

It will convert phenols into a triflic ester, which enables cleavage of the C-O bond.