Electrophilic versus free radical reactions of halogens and halogen systems with perfluoroalkenes and a perfluoroalkylethylene
作者:Dale F Shellhamer、Jeannette L Allen、Rachel D Allen、Melissa J Bostic、Elizabeth A Miller、Colleen M O’Neill、Benjamin J Powers、Eric A Price、John W Probst、Victor L Heasley
DOI:10.1016/s0022-1139(00)00319-5
日期:2000.10
Alkene 3 is more reactive and gives products with electrophiles Cl2, Br2, BrCl, and ICl from ring-opening of the halonium ions at the terminal carbon. Disubstituted perfluoroalkenes 2 and 4 did not react ionically with Cl2, Br2, BrCl, or ICl. Free radical reactions of Cl2, Br2, BrCl, and ICl give good yields of dihaloproducts with 1 and 3. Yields are poor for the photochemical bromination of disubstituted
用全氟庚烯-1(1),八氟环戊烯(2),1H,1H,2H-全氟辛烯-1(3)和全氟-4-甲基-2-戊烯(4)进行卤素系统的离子和自由基加成。在确保离子路径的反应条件下,用汞催化剂在叔丁醇中作为溶剂用氯处理末端烯烃1。溴在类似条件下不会与1反应。一氟化氯与1在二氯甲烷中的反应生成2-氯全氟庚烷。烯烃3更具反应性,并产生具有亲电子试剂Cl 2,Br 2的产物,BrCl和ICl是由于the离子在末端碳原子处的开环而产生的。二取代的全氟烯烃2和4不会与Cl 2,Br 2,BrCl或ICl发生离子反应。Cl 2,Br 2,BrCl和ICl的自由基反应可得到1和3的二卤代产物。双取代的全氟烯烃2和4的光化学溴化收率不佳,因为二溴代产物与烯烃处于光化学平衡。