Tin-mediated equilibration of the benzoate esters of methyl 4,6-O-benzylidene-α-d-glucopyranoside

The selective dibutyltin oxide-mediated benzoylation of methyl 4,6-O-benzylidene-α-d-glucopyranoside at position 2 is not a post-acylation phenomenon as is the case with the equivalent benzoylation of phenylethyleneglycol. 1H NMR temperature studies have shown that such equilibration occurs only above 85°C in toluene-d8 for the glucopyranoside.