Reactions of Perfluorinated Alkenyl-, Alkynyl-, Alkyltrifluoroborates, and Selected Hydrocarbon Analogues with the Halogenating Agents Hal2 (Hal = F, Cl, Br), “BrF” (BrF3-Br2 1:1), and ICl

Reactions of [Bu4N][RBF3] [R = CnF2n+1CF=CF (cis, trans), CF2=CF, CF2=C(CF3), trans-C4H9CF=CF, trans-C6H5CF=CF, C4H9CH=CH (cis, trans), CF3C≡C, and C4H9C≡C] with chlorine, bromine, BrF3 + Br2 (as equivalent of “BrF”), and ICl in solution (CH2Cl2, CHCl3, CF3CH2CF2CH3) led to 1, 2-addition of halogen and/or replacement of boron by halogen (halodeboration). The reaction of [Bu4N][CF3C≡CBF3] with less than equimolar amounts of diluted fluorine (5 %) in 1, 1, 1, 3, 3-pentafluorobutane (PFB) showed only [Bu4N][CF3CF2CF2BF3] as fluorine addition product besides extensive fluorodeboration. Suspensions of the insoluble K[CF2=CFBF3] salt reacted with Cl2 and Br2 in CH2Cl2 giving preferentially products of halogen addition across the C=C bond. In reactions with ICl iododeboration with formation of CF2=CFI occurred besides 1, 2-addition with formation of [CF2I–CFClBF3]–. The halodeboration reaction of[Bu4N][trans-C4H9CF=CFBF3] with Br2, “BrF”, and ICl, of K[trans-C6H5CF=CFBF3] with Br2, and of [Bu4N][trans-C4F9CF=CFBF3] with ICl proceeded stereospecifically.