An expeditious approach to various protected hexoses has been developed by the use of the Sharpless catalytic asymmetric dihydroxylation reaction. Applying the Sharpless catalytic asymmetric dihydroxylation reaction on vinylfuran, diols with high enantioexcess are produced. The resulting diols can be stereoselectively transformed into either protected D- or L-mannose in five steps and approximately 39% yield from furfural. Similarly, both D- and L-talose and gulose have been synthesized in 19% overall yields, respectively. Using a modified strategy, both protected D- and L-gulo- and allo-sugar-δ-lactones were synthesized in eight steps and ~-20% overall yield from furfural.
Bibliographical noteFunding Information:
We thank the University of Minnesota (Grant-in-Aid program), the ACS for an Institutional Research Grant (IRG-58-001-40-IRG-19), the American Chemical Society–Petroleum Research Fund (ACS–PRF#33953-G1) and the Arnald and Mabel Beckman Foundation for their generous support of our program. We would also like to thank Dr Dirk Friedrich (Hoechst Marion Roussel) for his help in the structure determination of 1a and 13 .
- AD mix
- Enantioselective synthesis
- Sugar lactone