Triflidic acid (''IUPAC name'': tris
trifluoromethyl)sulfonylethane, ''abbreviated formula'': Tf
3CH) is an organic
superacid. It is one of the strongest known
carbon acid
In organic chemistry, a carbanion is an anion in which carbon is trivalent (forms three bonds) and bears a formal negative charge (in at least one significant resonance form).
Formally, a carbanion is the conjugate base of a carbon acid:
:R3CH ...
s and is among the strongest
Brønsted acids in general, with an acidity exceeded only by the
carborane acids. Notably, triflidic acid is estimated to have an acidity 10
4 times that of
triflic acid
Triflic acid, the short name for trifluoromethanesulfonic acid, TFMS, TFSA, HOTf or TfOH, is a sulfonic acid with the chemical formula CF3SO3H. It is one of the strongest known acids. Triflic acid is mainly used in research as a catalyst for este ...
(p''K''
aaq ~ –14), as measured by its
acid dissociation constant. It was first prepared in 1987 by
Seppelt Seppelt is a German surname. Notable people with the surname include:
* Benno Seppelt (1846–1931), South Australian winemaker, son of Joseph
*Hajo Seppelt
Hajo Seppelt (born 1963) is a German journalist and author.
Personal life and educati ...
and Turowsky by the following route:
(1) Tf2CH2 + 2CH3MgBr → Tf2C(MgBr)2 + 2CH4
(2) Tf2C(MgBr)2 + TfF → Tf3C(MgBr) + MgBrF
(3) Tf3C(MgBr) + H2SO4 → Tf3CH + MgBrHSO4
In its anionic form, the lanthanide salts of triflidic acid ("triflides") have been shown to be more efficient Lewis acids than the corresponding triflates. The triflide anion has also been employed as the anionic component of ionic liquids.
See also
*
Bistriflimide
*
Non-coordinating anion
Anions that interact weakly with cations are termed non-coordinating anions, although a more accurate term is weakly coordinating anion. Non-coordinating anions are useful in studying the reactivity of electrophilic cations. They are commonly found ...
References
{{reflist
Superacids
Trifluoromethyl compounds