Octafluorocyclohexa-1: 4-diene gave, with oleum, tetrafluoro-p-benzoquinone which was reduced to the corresponding hydroquinone derivative, the dimethyl ether of which is identical with that formed from hexafluorobenzene and sodium methoxide. 1H- Heptafluorocyclohexa-1: 4-diene gave 2: 3: 5-trifluorohydroquinone in a similar way.
