Fluorine-containing allenes. Communication 7. Two directions for dehydrofluorination of 1-fluoro-1-(α-hydrohexafluoroisopropyl)ethylenes

1.	Depending on the nature of the substituent in the 2 position, l-fluoro-l-(-hydrohexafluoroisopropyl)ethylenes are dehydrofluorinated to either allenes or 1,3-dienes.
2.	It was shown that allylic substitution is possible in the reactions of perfluoroisobutylene with carbanions; the mutual transformations of the allyl and vinyl isomers were studied.
3.	The perfluoroalkenylation product was obtained when perfluoroisobutylene is reacted with ketene acetal.