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Stereoselective 1,2-cis Furanosylations Catalyzed by Phenanthroline.

ABSTRACT: Stereoselective formation of the 1,2-cis furanosidic linkage, a motif of many biologically relevant oligosaccharides and polysaccharides, remains an important synthetic challenge. We herein report a new stereoselective 1,2-cis furanosylation method promoted by phenanthroline catalysts under mild and operationally simple conditions. NMR experiments and density functional theory calculations support an associative mechanism in which the rate-determining step occurs from an inverted displacement of the faster-reacting phenanthrolinium ion intermediate with an alcohol nucleophile. The phenanthroline catalysis system is applicable to a number of furanosyl bromide donors to provide the challenging 1,2-cis substitution products in good yield with high anomeric selectivities. While arabinofuranosyl bromide provides β-1,2-cis products, xylo- and ribofuranosyl bromides favor α-1,2-cis products.

SUBMITTER: Xu H

PROVIDER: S-EPMC9093562 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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Stereoselective 1,2-cis Furanosylations Catalyzed by Phenanthroline.

Xu Hengfu H Schaugaard Richard N RN Li Jiayi J Schlegel H Bernhard HB Nguyen Hien M HM

Journal of the American Chemical Society 20220412 16

Stereoselective formation of the 1,2-cis furanosidic linkage, a motif of many biologically relevant oligosaccharides and polysaccharides, remains an important synthetic challenge. We herein report a new stereoselective 1,2-cis furanosylation method promoted by phenanthroline catalysts under mild and operationally simple conditions. NMR experiments and density functional theory calculations support an associative mechanism in which the rate-determining step occurs from an inverted d ...[more]

PMID: 35413194

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