Regioselective Synthesis of Vinylic Derivatives of Common Monosccarides Through Their Activated Stannylene Acetal Intermediates

Abstract: The regioselective C-2-O-acrylation and metacrylation of methyl 4,6-O-benzylidene-α-D-glucopyranoside and methyl 4,6-O-benzylidene-α-D-galactopyranosidethrough their corresponding organotin intermediates have been studied. Regioselectivitywas achived through the formation of a tin chelate of the 2,3-diols. Thus, methyl 4,6-O-benzylidene-α-D-glucopyranoside and methyl 4,6-O-benzylidene-α-D-galactopyranosidewere reacted with dibutylstannylene to give the corresponding dibutylstannylene acetalintermediates that were then reacted in a regioselective manner with acryloyl chloride ormetacryloyl chloride in the presence of triethylamine (TEA) or pyridine to give thevinylic type monomeric compounds. The monomeric products containing glucose andgalactose units from each reaction were separated by column chromatography using agradient of n-hexane and ethyl acetate as eluant. The structure of the obtained compoundswere confirmed using ¹H-, ¹³C- and 2D NMR spectroscopy.