Reactions of Perfluorinated Alkenyl‐, Alkynyl‐, Alkyltrifluoroborates, and Selected Hydrocarbon Analogues with the Halogenating Agents Hal 2 (Hal = F, Cl, Br), “BrF” (BrF 3 –Br 2 1:1), and ICl

Reactions of [Bu 4 N][ R BF 3 ] [ R = C n F 2 n +1 CF=CF ( cis , trans ), CF 2 =CF, CF 2 =C(CF 3 ), trans ‐C 4 H 9 CF=CF, trans ‐C 6 H 5 CF=CF, C 4 H 9 CH=CH ( cis , trans ), CF 3 C≡C, and C 4 H 9 C≡C] with chlorine, bromine, BrF 3 + Br 2 (as equivalent of “BrF”), and ICl in solution (CH 2 Cl 2 , CHCl 3 , CF 3 CH 2 CF 2 CH 3 ) led to 1, 2‐addition of halogen and/or replacement of boron by halogen (halodeboration). The reaction of [Bu 4 N][CF 3 C≡CBF 3 ] with less than equimolar amounts of diluted fluorine (5 %) in 1, 1, 1, 3, 3‐pentafluorobutane (PFB) showed only [Bu 4 N][CF 3 CF 2 CF 2 BF 3 ] as fluorine addition product besides extensive fluorodeboration. Suspensions of the insoluble K[CF 2 =CFBF 3 ] salt reacted with Cl 2 and Br 2 in CH 2 Cl 2 giving preferentially products of halogen addition across the C=C bond. In reactions with ICl iododeboration with formation of CF 2 =CFI occurred besides 1, 2‐addition with formation of [CF 2 I–CFClBF 3 ] – . The halodeboration reaction of[Bu 4 N][ trans ‐C 4 H 9 CF=CFBF 3 ] with Br 2 , “BrF”, and ICl, of K[ trans ‐C 6 H 5 CF=CFBF 3 ] with Br 2 , and of [Bu 4 N][ trans ‐C 4 F 9 CF=CFBF 3 ] with ICl proceeded stereospecifically.