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Asymmetric 'Clip-Cycle' synthesis of 3-spiropiperidines. | LitMetric

Asymmetric 'Clip-Cycle' synthesis of 3-spiropiperidines.

Org Biomol Chem

Department of Chemistry, University of York, Heslington, York, UK, YO10 5DD.

Published: November 2024

3-Spiropiperidines can be synthesized in up to 87% yield and 96 : 4 er using a two step 'Clip-Cycle' approach. The 'Clip' stage of this method is based on efficient and highly -selective cross metathesis of -Cbz-protected 1-amino-hex-5-enes with a thioacrylate. This is followed by the 'Cycle' step, in which an intramolecular asymmetric aza-Michael cyclization is promoted by a chiral phosphoric acid catalyst.

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Source
http://dx.doi.org/10.1039/d4ob01608dDOI Listing

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