F. Dasgupta et Pj. Garegg, MONOALKYLATION OF TRIBUTYLTIN ACTIVATED METHYL 4,6-O-BENZYLIDENE-ALPHA-D-GLUCOPYRANOSIDE AND 4,6-O-BENZYLIDENE-ALPHA-D-GALACTOPYRANOSIDE, Synthesis, (11), 1994, pp. 1121-1123
Mono alkylation of methyl 4,6-O-benzylidene-alpha-D-gluco - and galact
opyranosides could be carried out in good yields using bis(tributyltin
) oxide. Regioselectivity, giving predominant 2-substitution, was exce
llent in the case of D-glucopyranoside. The ratio of the tin reagent t
o that of the substrate seems to be critical in determining the yield
and the extent of regioselectivity. Alkylation could also be carried o
ut in solvents at a slower rate, using less reagent, but the regiosele
ctivity was lower.