Highly diastereoselective C → N acyl rearrangement in polysubstituted pyrrolidine 2,2-dicarboxylates. Stereocontrolled synthesis of densely functionalized prolines

Abstract

An efficient and easy protocol for promoting a C → N acyl transfer reaction in diverse enantiopure densely substituted pyrrolidine 2,2-dicarboxylates was performed, yielding the corresponding proline ester derivatives with yields in the range of 68–99% and total diastereoselection (dr > 95 : 5 in all cases). The substitution patterns both at C-3 and C-5 present in starting pyrrolidines as well as the viability of presenting different alkoxycarbonyl moieties have been evaluated observing good reaction performance in all cases.