Efficient synthesis of rare sugar D-allal via reversal of diastereoselection in the reduction of protected 1,5-anhydrohex-1-en-3-uloses: protecting group dependence of the stereoselection

Takashi Fujiwara; Masahiko Hayashi

doi:10.1021/jo801596q

Efficient synthesis of rare sugar D-allal via reversal of diastereoselection in the reduction of protected 1,5-anhydrohex-1-en-3-uloses: protecting group dependence of the stereoselection

J Org Chem. 2008 Nov 21;73(22):9161-3. doi: 10.1021/jo801596q. Epub 2008 Oct 14.

Authors

Takashi Fujiwara¹, Masahiko Hayashi

Affiliation

¹ Department of Chemistry, Graduate School of Science, Kobe University, Nada, Kobe 657-8501.

PMID: 18850745
DOI: 10.1021/jo801596q

Abstract

D-allal was selectively obtained by reducing bulky-silyl-protected 1,5-anhydrohex-1-en-3-uloses using the NaBH4CeCl3 x 7 H2O system. The crucial point of this synthesis is the nature of the protecting group. When bulky silyl group such as t-butyldiphenylsilyl was used as substrate, protected D-allal was obtained in >99% selectivity. In contrast, when acetylated enone was used, protected D-glucal was obtained exclusively. The addition of CeCl3 x 7 H2O was also found to influence selectivity.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Hexoses / chemical synthesis*
Hexoses / chemistry*
Oxidation-Reduction
Stereoisomerism
Substrate Specificity

Substances

Hexoses