Memory of Chirality in the Asymmetric Synthesis of Piperidines with Vicinal Stereocenters by Intramolecular Sn2'
Seungbae Park1, Seokwoo Lee1, Jae Hyun Kim1,2
1College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea.
Abstract:
Intramolecular Sn2' cyclization of α-amino ester enolates provided piperidine derivatives with vicinal quaternary-tertiary stereocenters with excellent diastereo- and enantioselectivity via memory of chirality and the Thorpe-Ingold effect. DFT calculations provided a mechanistic rationale for the increase in chirality preservation via the Thorpe-Ingold effect. This new method has the potential to be integrated into concise asymmetric synthesis of bioactive molecules containing multisubstituted piperidine moieties.
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