Kinetic and dynamic kinetic resolution of racemic tertiary bromides by pentanidium‐catalyzed phase‐transfer azidation

We have developed a method to afford enantiomerically enriched tertiary azides and bromides through pentanidium-catalyzed kinetic resolution (KR) of racemic tertiary bromides under base-free conditions. We found that the absence of water is crucial to attain a high selectivity factor (s). On the oth...

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Bibliographic Details
Main Authors: Ren, Jingyun, Ban, Xu, Zhang, Xin, Tan, Siu Min, Lee, Richmond, Tan, Choon-Hong
Other Authors: School of Chemistry, Chemical Engineering and Biotechnology
Format: Journal Article
Language:English
Published: 2023
Subjects:
Online Access:https://hdl.handle.net/10356/170451
Description
Summary:We have developed a method to afford enantiomerically enriched tertiary azides and bromides through pentanidium-catalyzed kinetic resolution (KR) of racemic tertiary bromides under base-free conditions. We found that the absence of water is crucial to attain a high selectivity factor (s). On the other hand, new experimental observations and DFT modeling led us to propose that enantioconvergent azidation of tertiary bromides proceeded through dynamic kinetic resolution (DKR). The investigations particularly identified the crucial roles of base and water in the enantioconvergent process, thus supporting the proposal that the tertiary bromide isomerizes in the presence of base and water through a SN2X pathway.