Unique ionic iodine atom transfer cyclization: a new route to iodomethylated pyrrolidine derivatives from gamma-iodoolefin and chloramine-T.

[reaction: see text] Pyrrolidines and bicyclic pyrrolidine derivatives can effectively be synthesized from gamma-iodoolefins using commercially available chloramine-T (CT) as a nitrogen source. The cyclization proceeds with high stereoselectivity via a cyclic iodonium intermediate.