Isomerisation of aldoses in pyridine in the presence of aluminium oxide.

Carbohydr Res

Department of Chemistry, Biotechnology and Food Science, Section Chemistry, Agricultural University of Norway, As, Norway.

Published: February 2005

Addition of aluminium oxide to boiling pyridine solutions of D-xylose, L-arabinose, D-mannose and D-glucose strongly increased the reaction rate of the aldose-ketose transformation. The maximum content of 2-ketose was reached after less than 2h for the aldopentoses and 3h for the aldohexoses. D-Threo-2-pentulose (xylulose) was prepared from D-xylose, and isolated as its O-isopropylidene derivative, the yield was nearly twice that compared to that usually obtained in the classical Lobry de Bruyn-Alberda van Ekenstein transformation in pyridine.

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http://dx.doi.org/10.1016/j.carres.2004.12.006DOI Listing

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