ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Stereospecific Molybdic Acid-Catalyzed Isomerization of D-Fructose to Branched-Chain Aldose. The Synthesis of D-Hamamelose

Z. Hricovíniová, M. Hricovíni, and L. Petruš

Institute of Chemistry, Slovak Academy of Sciences, SK-842 38 Bratislava

Abstract: One-step, stereospecific synthesis of D-hamamelose (2-C-(hydroxymethyl)-D-ribose) by isomerization of D-fructose in mild acidic aqueous solution, under catalytic amount of molybdic acid, is described. The mechanism of this transformation was proposed, studied, and confirmed. The data obtained with D-(2¹³-C)fructose indicate that the rearrangement of 2-ketose to branched-chain aldose is analogical to the mechanism of C-2-epimerization of aldoses catalyzed by molybdate ions. The structure of the branched-chain aldose, D-(2¹³-C)hamamelose documents that the stereospecific reaction is accompanied by the carbon skeletal rearrangement. The equilibrium mixture of D-fructose and D-hamamelose is formed in the ratio of 14:1 regardless of the starting sugar, D-hamamelose or D-fructose.

Full paper in Portable Document Format: 525a692.pdf

Chemical Papers 52 (5) 692–698 (1998)