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Synthesis of Glycosyl Chlorides and Bromides by Chelation Assisted Activation of Picolinic Esters under Mild Neutral Conditions.

ABSTRACT: A general method has been developed for the formation of glycosyl chlorides and bromides from picolinic esters under mild and neutral conditions. Benchtop stable picolinic esters are activated by a copper(II) halide species to afford the corresponding products in high yields with a traceless leaving group. Rare ? glycosyl chlorides are accessible via this route through neighboring group participation. Additionally, glycosyl chlorides with labile protecting groups previously not easily accessible can be prepared.

SUBMITTER: Wen P

PROVIDER: S-EPMC7050992 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Synthesis of Glycosyl Chlorides and Bromides by Chelation Assisted Activation of Picolinic Esters under Mild Neutral Conditions.

Wen Peng P Simmons Christopher J CJ Ma Zhi-Xiong ZX Blaszczyk Stephanie A SA Balzer Paul G PG Ye Wenjing W Duan Xiyan X Wang Hao-Yuan HY Yin Dan D Stevens Christopher M CM Tang Weiping W

Organic letters 20200206 4

A general method has been developed for the formation of glycosyl chlorides and bromides from picolinic esters under mild and neutral conditions. Benchtop stable picolinic esters are activated by a copper(II) halide species to afford the corresponding products in high yields with a traceless leaving group. Rare β glycosyl chlorides are accessible via this route through neighboring group participation. Additionally, glycosyl chlorides with labile protecting groups previously not easily accessible ...[more]

PMID: 32026682

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