4-De­oxy-4-fluoro-β-d-gluco­pyranose

摘要

4-De­oxy-4-fluoro-β-d-glucopyran­ose, C6H11FO5, (I), crystallizes from water at room temperature in a slightly distorted ⁴ C 1 chair con­formation. The observed chair distortion differs from that observed in β-d-glucopyran­ose [Kouwijzer, van Eijck, Kooijman & Kroon (1995). Acta Cryst. B>51, 209–220], (II), with the former skewed toward a B ^C3,O5 (boat) conformer and the latter toward an ^O5 TB C2 (twist–boat) conformer, based on Cremer–Pople analysis. The exocyclic hy­droxy­methyl group conformations in (I) and (II) are similar; in both cases, the O—C—C—O torsion angle is ∼−60° (gg con­former). Inter­molecular hydrogen bonding in the crystal structures of (I) and (II) is conserved in that identical patterns of donors and acceptors are observed for the exocyclic substituents and the ring O atom of each monosaccharide. Inspection of the crystal packing structures of (I) and (II) reveals an essentially identical packing configuration.