1,6-anhydro-/?-D-hexopyranoses

Cleophax et al. [21] used intramolecular protection in the large-scale preparation of 1,6-anhydro-D-hexopyranoses (45-86%) from the corresponding monotosylates. For ditosylate 37, a mild, rapid, and solvent-free microwave procedure was used. Interestingly, 38 (55%) and l,6 2,3-di-anhydro-4-0-acetyl-jff-D-glucopyranose (39) (approx. 5%) were obtained after re-acetylation (Scheme 12.15). 

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