1,3,4-Tri-O-acetyl-2-N-(tri-fluoro-acetyl)-β-l-fucose.

The title compound, C14H18F3NO8, was produced through conjugation of 1,3,4-tri-O-acetyl-2-azidode-oxy-α,β-l-fucose with tri-fluoro-acetyl chloride in the presence of bis-(di-phenyl-phosphino)ethane in tetra-hydro-furan at room temperature. The X-ray crystal structure reveals that the β-anomer of the product mixture crystallizes from ethyl acetate/hexa-nes. The compound exists in a typical chair conformation with the maximum possible number of substituents, four out of five, located in the sterically preferred equatorial positions. The major directional force facilitating packing of the mol-ecules are N-H⋯O hydrogen bonds involving the amide moieties of neighboring mol-ecules, which connect mol-ecules stacked along the a-axis direction into infinite strands with a C (1) 1(4) graph-set motif. Formation of the strands is assisted by a number of weaker C-H⋯O inter-actions involving the methine and methyl H atoms. These strands are connected through further C-H⋯O and C-H⋯F inter-actions into a three dimensional network.