A NEW METHOD OF ACETONATION WITH THE ZEOLITE HY AS CATALYST - SYNTHESIS OF O-ISOPROPYLIDENE SUGAR-DERIVATIVES

Zeolite HY proved to be a suitable catalyst for the acetonation of sugars. The method consists of a very simple and economic experimental procedure, in which the catalyst is recovered and can be regenerated Reaction with D-galactose, L-arabinose, D-glucose, D-xylose, L-sorbose, D-glucofuranurono-6,3-lactone, D-ribose and its methyl glycoside led to the formation of di-O- and/or mono-O-isopropylidene derivatives in yields from 37-75%. Reaction with D-galactose and L-arabinose afforded the synthesis of the corresponding furanose derivatives as major products, together with minor quantities of the thermodynamically more stable pyranose derivatives.