Acid Catalyzed Dehydration of Alditols. Part I. D-Glucitol and D-Mannitol.

Abstract

The acid catalyzed dehydration of D-glucitol and D-mannitol was studied using 13C NMR spectroscopy to monitor the reactions. The products formed were identified and rate constants were measured. Dehydration of (1S)-1-2H-D-mannitol with 3 M sulfuric acid was shown to yield (1R)-1-2H-1,4:3,6-dianhydro-D-mannitol, showing that dehydration of D-mannitol to 1,4-anhydro-D-mannitol and, subsequently, to the 1,4:3,6-dianhydride takes place with inversion at the primary carbon atom.