Nucleophilic 5-endo-trig cyclizations of N-homoallylic sulfonamides: a facile method for the construction of pyrrolidine rings.
Normally disfavored 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.
Ichikawa
Junji
J
Department of Chemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, Japan. junji@chem.s.u-tokyo.ac.jp
Lapointe
Guillaume
G
Iwai
Yu
Y