MONOALKYLATION OF TRIBUTYLTIN ACTIVATED METHYL 4,6-O-BENZYLIDENE-ALPHA-D-GLUCOPYRANOSIDE AND 4,6-O-BENZYLIDENE-ALPHA-D-GALACTOPYRANOSIDE

Mono alkylation of methyl 4,6-O-benzylidene-alpha-D-gluco - and galactopyranosides could be carried out in good yields using bis(tributyltin) oxide. Regioselectivity, giving predominant 2-substitution, was excellent in the case of D-glucopyranoside. The ratio of the tin reagent to that of the substrate seems to be critical in determining the yield and the extent of regioselectivity. Alkylation could also be carried out in solvents at a slower rate, using less reagent, but the regioselectivity was lower.