Asymmetric radical cyclizations: The synthesis of 6-alkyl pyrrolizidin-2-ones

Article abstract of DOI:10.1016/S0040-4020(01)92242-2

This work describes the use of ethyl (5S)-carboethoxy-2-pyrrolidinone (ethyl pyroglutamate) as a chiral starting material for use in radical cyclization reactions. Pyroglutamate is converted to a 5-iodomethyl-N-allylic-2-pyrrolidinone that undergoes radical cyclization under mild conditions. The products are 6-substituted pyrrolizidinone derivatives, produced with high diastereoselectivity.