Nonafluoro-tert-butyl alcohol (IUPAC name: 1,1,1,3,3,3-hexafluoro-2-(trifluoromethyl)propan-2-ol) is a fluoroalcohol. It is the perfluorinated analog of tert-butyl alcohol. Notably, as a consequence of its electron withdrawing fluorine substituents, it is very acidic for an alcohol, with a pKa value of 5.4, similar to that of a carboxylic acid. As another consequence of being a perfluorinated compound, it is also one of the lowest boiling alcohols, with a boiling point lower than that of methanol.
It is prepared by addition of trichloromethyllithium to hexafluoroacetone, followed by halogen exchange with antimony pentafluoride.[1] The aluminate derived from its alkoxide anion, tetrakis[1,1,1,3,3,3-hexafluoro-2-(trifluoromethyl)propan-2-oxy]aluminate(1–), – is used as a weakly coordinating anion.[2]