MilliporeSigma
  • Zeolite-catalyzed Helferich-type glycosylation of long-chain alcohols. Synthesis of acetylated alkyl 1,2-trans glycopyranosides and alkyl 1,2-cis C2-hydroxy-glycopyranosides.

Zeolite-catalyzed Helferich-type glycosylation of long-chain alcohols. Synthesis of acetylated alkyl 1,2-trans glycopyranosides and alkyl 1,2-cis C2-hydroxy-glycopyranosides.

Carbohydrate research (2007-01-16)
Udayanath Aich, Duraikkannu Loganathan
ABSTRACT

Zeolite-catalyzed glycosylation of long-chain alcohols, using the inexpensive and readily available peracetylated beta-D-gluco- and galactopyranoses as glycosyl donors under solvent free conditions, has been explored for the first time. Among the various forms (H-, Na-, Fe- and Zn) of beta zeolite examined as catalysts in the reaction of 1,2,3,4,6-penta-O-acetyl-beta-D-galactopyranose with cetyl alcohol, Fe-beta zeolite gave the maximum yield of 63% of cetyl 2,3,4,6-tetra-O-acetyl-beta-D-galactopyranoside and cetyl 3,4,6-tri-O-acetyl-alpha-D-galactopyranoside. Fe-beta Zeolite-catalyzed glycosylation was found to be general affording the title compounds in each case in a moderate yield, but with a good stereoselectivity. The yield of synthetically valuable acetylated long-chain alkyl 1,2-cis C2-hydroxy-glycopyranosides obtained in the present single-step procedure is considerably higher than that of the previously reported multi-step method employing the Stork silicon tether approach.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
β-D-Galactose pentaacetate, 98%
Sigma-Aldrich
1-Hexadecanol, 95%
Sigma-Aldrich
1-Hexadecanol, ≥99%
Sigma-Aldrich
1-Hexadecanol, ReagentPlus®, 99%
Cetyl alcohol, European Pharmacopoeia (EP) Reference Standard
Supelco
Cetyl alcohol, analytical standard
Supelco
Cetyl Alcohol, Pharmaceutical Secondary Standard; Certified Reference Material