Stereoselective synthesis of 2,4,5-trisubstituted piperidines by carbonyl ene and Prins cyclisations
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Updated: Aug 14, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Claire A M Cariou1, John S Snaith
1School of Chemistry, University of Birmingham, Edgbaston, Birmingham, UK B15 2TT.
Abstract:
Cyclisation of aldehydes 3-e catalysed by concentrated hydrochloric acid affords predominantly the all cis 2,4,5-trisubstituted piperidines 4a-ewhen the 2-substituent is small, while catalysis by MeAlCl2 in refluxing chloroform gives the trans piperidines 5a-e with diastereomeric ratios of up to 99:1.
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