Reactions of tetrachlorodiborane(4) with fluoroolefins

Tetrachlorodiborane(4) reacts with trifluoroethylene to give dichloro-2,2- difluorovinylborane and both isomers of dichloro-2-chloro-2-fluorovinylborane. These compounds can be converted to the corresponding difluoro (halovinyl)boranes by treatment with SbF₃. Reaction of B₂Cl₄ with vinyl fluoride gives 1,1,2-tris(dichloroboryl)ethane. A facile halogen exchange with B₂Cl₄, was observed for a number of fluoroolefins, includin vinyl fluoride, 1,1-difluoroethylene, 2-fluoropropene, and 3,3,3-trifluoropropene. No reaction was observed with 2,3,3,3-tetrafluoropropene.