5-endo-trig cyclizations proceed in N-homoallylsulfonamides bearing a CF(3), CCl(3), CO(2)Et or CN group at the C-3 position, via an intramolecular S(N)2'-type or addition reaction to construct pyrrolidine rings, even though the system allows a more favorable 5-exo-trig pathway.
通常不受欢迎的5-endo-trig环化反应是通过分子内S(N)2'-在C-3位置带有CF(3),CCl(3),CO(2)Et或CN基团的N-均烯丙基磺酰胺中进行的。类型或加成反应以构建
吡咯烷环,即使该系统允许使用更有利的5-exo-trig途径。