Stereoselective C-glycosylation reactions of pyranoses: The conformational preference and reactions of the mannosyl cation

Claudia G. Lucero, Keith Woerpel

Research output: Contribution to journalArticle

Abstract

A systematic study of C-glycosylations of acetals related to mannose and other pyranoses was conducted. The C-5 alkoxyalkyl group provides only a modest influence on stereoselectivity. On the other hand, studies of pentopyranoses bearing alkoxy groups at C-2, C-3, and C-4 showed that the alkoxy groups exerted powerful influences on selectivity. In the case of mannose, the high αselectivity observed with C-mannosylation was reversed to high β selectivity if the C-5 alkoxyalkyl group were removed. An analysis of the conformational preferences of the intermediate oxocarbenium ions, including the mannosyl cation, as well as consideration of steric effects that develop in the transition states for nucleophilic attack provide explanations for these phenomena.

Original languageEnglish (US)
Pages (from-to)2641-2647
Number of pages7
JournalJournal of Organic Chemistry
Volume71
Issue number7
DOIs
StatePublished - Apr 1 2006

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Glycosylation
Mannose
Cations
Bearings (structural)
Stereoselectivity
Acetals
Ions
alkoxyl radical

ASJC Scopus subject areas

  • Organic Chemistry

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Stereoselective C-glycosylation reactions of pyranoses : The conformational preference and reactions of the mannosyl cation. / Lucero, Claudia G.; Woerpel, Keith.

In: Journal of Organic Chemistry, Vol. 71, No. 7, 01.04.2006, p. 2641-2647.

Research output: Contribution to journalArticle

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