Acetic Anhydride → 1,2,3,4,6-Penta-O-acetyl-D-mannopyranose

Beteiligte Stoffe

Reaktionsschritte

Analogously to what is described in the literature [M. L. Wolfrom and A. Thompson in Methods in Carbohydrate Chemistry (R. L. Whistler, M. L. Wolfrom and J. N. BeMiller, Eds.), Academic Press, New York, Vol. II, 53, pp. 211-215, (1963)], the reaction of 150 g (832.5 mmol) of α,β-D-mannopyranose with a mixture that consists of 1500 ml of absolute pyridine and 1500 ml of acetic acid anhydride yields, after working-up, 315 g (96.7%) of the above-mentioned title compound as a crude product in the form of a viscous and colorless oil. By 1H-NMR spectroscopic study of the thus obtained title compound, it was possible to determine the a to β ratio of both anomers at 4:1. Separation of the α,β-anomers of the above-mentioned title compound can be eliminated to carry out the reaction steps below.

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