Synthesis of 2,3,4-Trideoxy-2,3,4-trifluoroglucose.

There is an increasing interest in investigating how polyfluorination of carbohydrates modifies their physical and biological properties. An example that has caught much attention is 2,3,4-trideoxy-2,3,4-trifluoroglucose. Four syntheses of this compound have been reported, which are either low yielding or long (13 or more steps). We report a 6-step synthesis of 2,3,4-trideoxy-2,3,4-trifluoroglucose starting from levoglucosan. The solution-phase structure of an intermediate, 1,6-anhydro-2,4-dideoxy-2,4-difluoroallose, features a rare example of a bifurcated F···H(O)···F hydrogen bond and is compared to its crystal structure.