Isomerisation of aldoses in pyridine in the presence of aluminium oxide.
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.
Ekeberg
Dag
D
Department of Chemistry, Biotechnology and Food Science, Section Chemistry, Agricultural University of Norway, As, Norway.
Morgenlie
Svein
S
Stenstrøm
Yngve
Y
D000537:Aluminum Oxide / Q000737:chemistry*; D007536:Isomerism; D009005:Monosaccharides / Q000737:chemistry*; D011725:Pyridines / Q000138:chemical synthesis / Q000737:chemistry*
D009005:Monosaccharides; D011725:Pyridines; D000537:Aluminum Oxide; C023666:pyridine