Hexafluoro-2-butyne

Hexafluoro-2-butyne is the fluorocarbon with the formula CF3C≡CCF3. HFB, as it is known also, is a particularly electrophilic acetylene, hence a potent dienophile.

It is prepared by the action of sulfur tetrafluoride on acetylenedicarboxylic acid and the reaction of KF with hexachlorobutadiene.