Kristallstruktur von 2,3,4-tri-O-acetyl-β-D- xylopyranosylchlorid

Although 2,3,4-tri-O-acetyl-β-D-xylopyranosyl chloride is shown by n.m.r. data to be 80 percent in the ¹C₄ conformation in chloroform solution, it crystallizes in the normal ⁴C₁ conformation as shown by a three-dimensional, X-ray structure analysis. The crystals are orthorhombic, space group P2₁2₁2₁. The phase problem was solved by the heavy-atom method. The parameters were refined to an R-value of 0.039 for 1101 structure factors. With the chlorine atom being in equatorial position in the ⁴C₁ conformation, the C-1O-6 bond is not shortened and the C-1Cl-1 bond is not lengthened. These results are in agreement with comparable values for cis-2,3-dichloro-1,4-dioxane.