Fluoroölefins. V. The Synthesis of 1,1-Difluoro-3-methylbutadiene¹

Organic Fluorine Chemistry

“…This reagent does not, as a rule, replace single halogen atoms bound to carbon [95). It is especially suited for partial or complete replacement of halogens by fluorine in all kinds of organic geminal polyhalides.…”

“…Such replacements are very easy in polyhalogeno groups adjacent to double bonds or aromatic nuclei [96][97][98]. In all other instances, very energetic conditions such as temperatures in excess of IOOoe and the corresponding pressures must be applied [95) unless catalysts are used. The classic antimony trichloride-antimony pentachloride catalyst suitable for liquid-phase fluorinations is still in use [99,100).…”

“…In this respect, 1,2-dibrometetrafluoroethane is even better, but much more expensive (232). (95) CBrFs ~CHFa (96) Trade marks of refrigerants, their physical properties, and the vapor pressures of some of them are listed in Tables 28, 29, and 30, respectively.…”