Résumé
Reaction of perfluoroallyl chloride with perfluoroalkyl iodides, R
FI (R
F = C
4F
9, C
6F
13, C
8F
17), in an autoclave at 180–250 °C gave terminal perfluoroolefins, CF
2-CF-CF
2-R
F (
2–4) as the sole reaction products. Isomeric fluoroolefins containing an internal double bond and telomeric products were not observed in the reaction mixture. The yields were dependent on the reaction temperature and on the chain length of R
FI: the highest preparative yield of olefin
2 (R
F = C
4F
9) was obtained at 200 °C (26%), while in the syntheses of olefins
3 and
4 (R
F = C
6F
13 and C
8F
17, respectively) highest yields were achieved at 250 °C (41% and 74%, respectively). The presence of CuI or a peroxide initiator had a negative influence on the yield of products. Formulae have been assigned to the fragments in the mass spectra of products
2–4, and fragmentation sequences have been proposed.