Synthesis of N-tosyl-3,3,4-trisubstituted pyrrolidine derivatives starting from the Baylis–Hillman adducts via radical cyclization

Abstract

N-Tosyl-3,3-disubstituted-4-vinylpyrrolidine derivatives 3a– c were synthesized via radical cyclization from the modified Baylis–Hillman adducts 2. The required starting materials 2a– c were prepared in moderate yields from the Baylis–Hillman adducts in three steps: (i) acetylation of the Baylis–Hillman adducts, (ii) S N2′ reaction with tosylamide to prepare 1, and (iii) alkylation with 1,4-dibromo-2-butene.