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Diastereoselective synthesis and conformational analysis of 4,5-difluoropipecolic acids. | LitMetric

Diastereoselective synthesis and conformational analysis of 4,5-difluoropipecolic acids.

Org Biomol Chem

National Engineering Research Center for Carbohydrate Synthesis, Jiangxi Normal University, Nanchang 330022, P. R. China. and Key Laboratory of Small Functional Organic Molecules, Jiangxi Normal University, Nanchang, 330022, P. R. China.

Published: October 2020

AI Article Synopsis

Article Abstract

Stereoselectively-fluorinated analogs of pipecolic acid have been investigated through a combined theoretical and experimental approach. Three of the four possible diastereoisomers of 4,5-difluoropipecolic acid were successfully synthesized via deoxyfluorination chemistry, navigating a complex reaction network that included neighboring group participation, rearrangement, and elimination pathways. A DFT-based conformational study, supported by NMR J-based analysis, revealed that the different diastereoisomers of 4,5-difluoropipecolic acid preferentially adopt different puckers of the six-membered ring. These findings could have future relevance for the conformational control of biologically active peptides.

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Source
http://dx.doi.org/10.1039/d0ob01811bDOI Listing

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