Fluoro-olefin chemistry. Part 11. Some reactions of perfluoro-3-methylbut-1-ene under ionic and free-radical conditions

Abstract

The reactions of hydrogen bromide, N-bromobistrifluoromethylamine, methanethiol, and trimethylsilane with perfluoro-3-methylbut-1-ene under free-radical conditions proceed by attack by Br·, (CF₃)₂N·, MeS·, and Me₃Si· exclusively at the terminal CF₂ group. Fluoride ion rearranges the olefin to perfluoro-2-methylbut-2-ene, and methoxide ion affords a complex mixture of products derived from both the reactant and rearranged olefins. Dimethylamine gives the unexpected 1 : 1 adduct, (CF₃)₂CH·CF₂·CF₂·NMe₂ and the corresponding amide (CF₃)₂CH·CF₂·CO·NMe₂. Catalytic hydrogenation of the olefin proceeds normally to give 1H,2H-3-trifluoromethylheptafluorobutane.