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Updated: May 27, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Diastereoselective access to nonracemic 2-cis-substituted and 2,6-cis-disubstituted piperidines
Nicolas Coia1, Naïma Mokhtari, Jean-Luc Vasse
1Institut de Chimie Moléculaire de Reims, CNRS (UMR 6229) and Université de Reims, 51687 Reims Cedex 2, France.
Abstract:
Access to nonracemic amino ketones via a hydrozirconation/transmetalation/acylation sequence applied to Boc-protected 1-aminobut-3-enes is presented. This method was applied to the stereoselective synthesis of cyclic imines (or iminiums) which were diastereoselectively converted into 2-cis-substituted and 2,6-cis-disubstituted piperidines. The potential of this approach in the field of alkaloid synthesis was illustrated by the synthesis of (-)-coniine and (-)-indolizidine 209D. Furthermore, access to indolizidines bearing a quaternary center could also be envisioned through this strategy.
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