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 pK<sub>a</sub> 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. The aluminate derived from its alkoxide anion, tetrakis[1,1,1,3,3,3-hexafluoro-2-(trifluoromethyl)propan-2-oxy]aluminate(1âÂÂ), is used as a weakly coordinating anion.