The Crystal Structure of Levoglucosan Triacetate

Abstract

The crystal structure of the acetylated levoglucosan (1,6-anhydro-2,3,4-triacetylglucose) was determined by X-ray crystallography. The crystal data are: P212121, a = 10.916, b = 8.318, c = 15.612 Å. It was found that the pyranose ring of the molecule has the 1C(D) chair conformation with the acetate groups occupying the axial positions. The orientation of the acetate groups with respect to the pyranose ring was discussed in conjunction with other acetylated carbohydrate structures.

The crystal structure of 3-amino-1,6-anhydro-3-deoxy-β-D-glucopyranose by neutron diffraction

“…(The data reported below for this compound are with reference to the atomic notation for a 1,6-anhydro ring system, to facilitate comparison with the other structures.) (Leung & Marchessault, 1974).…”

3,4-Di-O-acetyl-2,5-anhydro-1,6-di-O-(p-tolylsulfonyl)-D-mannitol

“…The acetyl groups have an (S)-cis conformation with the C---O and C==O bonds eclipsed. This is the conformation most commonly observed in simple esters (Leung & Marchessault, 1974;Shalaby, Fronczek & Younathan, 1994). The acetyl groups are planar, with the non-H atoms deviating by less than 0.002/~, from their mean plane.…”

Deformations around a bond

“…1.1(7) 179.7(4) 1.4(8) 0.4(8) Foces-Foces et al, 1975 -1.3(14) 178.4(8) 0.3(16) -1.5(16) " 2.8(11) -177.2(7) 0.0(13) 2.8(13) Herpin et al, 1976 -3.7(12) 177.7(6) -1.4(13) -3.0(13) " 0.9(8) -179.7(5) 0.6(9) 0.6(9) " 11.0(9) -169.3(5) 0.3(10) 10.9(10) ' -1.6(7) 177.5(4) 0.9(8) -2.1(8) Leung et al,!973 9.4(10) -171.8(6) 1.2(12) 8.8(12) " 6.1(8) -172.5(5) -1.4(9) 6.8(9) " 7.6(11) -172.8(6) 0.4(13) 7.4(13) " 1.6(11) -178.3(7) -0.1(13) 1.7(13) " 0.4(11) -177.6(7) -2.0(13) 1.4(13) " -1.3(13) 178.9(7) -0.2(15) -I.2(15) Leung et al, 1974 -0.6(5) 178.9(3) 0.5(6) -0.9(6) Foces-Foces et al, 1976c -5.0(7) 173.1(5) 1.9(9) -6.0(9) L6pez de Lerma et al, 1973 -4.4(8) I77.5(4) -1.9(9) -3.5(9) Leung et al, 1974 0.9(6) 179.5(3) 1.4(7) 0.2(7) Foces-Foees et al, 1976a 6.4(5) -175.0(3) 1.4(6) 5.7(6) Lindberg, 1976b -6.9(7) I78.5(5) -5.4(9) -4.2(9) Heitmann et al, 1974 -3.3(7) 179.0(5) -2.3(8) -2.2(8) Leung et al, 1974 1.9(4) -176.0(3) -2.1(5) 3.0(5) -66.8 (7) 171.7 (6) 43.4 (7) 118.0 (7) -3.4 (7) -131.7 (6) 4.9 (10) 1.5 (9) 9.7(10) -6.7 (7) 6.0 (6) 3.0 (7) -3.0(6) -25.5(7) Kruger et al, 1972 -81.5(6) 120.3 (6) 30.3 (7) 100.1 (7) -58.2 (6) -148.2 (7) 1.5 (9) 38,2 (8) 8.2 (9) -30.0 (9) 23.8(9) Kalman et al, 1971 -97.9(6) 142.1 (6) 14.3 (6) 82.8(6) -37.2 (7) - 165 (c) compounds containing the phe...…”