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Fluorine effect in nucleophilic fluorination at C4 of 1,6-anhydro-2,3-dideoxy-2,3-difluoro-?-D-hexopyranose.

ABSTRACT: In this work, we have developed a simple synthetic approach using Et₃N·3HF as an alternative to the DAST reagent. We controlled the stereochemistry of the nucleophilic fluorination at C4 of 1,6-anhydro-2,3-dideoxy-2,3-difluoro-4-O-triflate-?-?-talopyranose using Et₃N·3HF or in situ generated Et₃N·1HF. The influence of the fluorine atom at C2 on reactivity at C4 could contribute to a new fluorine effect in nucleophilic substitution. Finally, with the continuous objective of synthesizing novel multi-vicinal fluorosugars, we prepared one difluorinated and one trifluorinated alditol analogue.

SUBMITTER: Laine D

PROVIDER: S-EPMC7705882 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Fluorine effect in nucleophilic fluorination at C4 of 1,6-anhydro-2,3-dideoxy-2,3-difluoro-β-D-hexopyranose.

Lainé Danny D Denavit Vincent V Lessard Olivier O Carrier Laurie L Fecteau Charles-Émile CÉ Johnson Paul A PA Giguère Denis D

Beilstein journal of organic chemistry 20201125

In this work, we have developed a simple synthetic approach using Et3N·3HF as an alternative to the DAST reagent. We controlled the stereochemistry of the nucleophilic fluorination at C4 of 1,6-anhydro-2,3-dideoxy-2,3-difluoro-4-O-triflate-β-ᴅ-talopyranose using Et3N·3HF or in situ generated Et3N·1HF. The influence of the fluorine atom at C2 on reactivity at C4 could contribute to a new fluorine effect in nucleophilic substitution. Finally, with the contin ...[more]

PMID: 33299486

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The Effect of Deoxyfluorination on Intermolecular Interactions in the Crystal Structures of 1,6-Anhydro-2,3-epimino-hexopyranoses.

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Molecular basis of 1,6-anhydro bond cleavage and phosphoryl transfer by Pseudomonas aeruginosa 1,6-anhydro-N-acetylmuramic acid kinase.

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2,3-Difluoro-N-(2-pyrid-yl)benzamide.

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