Structure elucidation of the dibutylchlorostannyl intermediate during dibutyltin oxide-mediated acylation of sugars

119Sn NMR and APcI-MS indicate the presence of a dimeric species as the dibutylchlorostannyl intermediate after dibutyltin oxide-mediated bezoylation of methyl 4,6-O-benzylidene-α-d-glucopyranoside. The stannyl groups in the dimer dismutate to form a dialkoxystannyl species loosely complexed to dibutyltin dichloride. This species and its isomer were also prepared by treating the benzoylated sugar with bis(dibutylchlorotin) oxide. The dialkoxytin complex and isomer was also prepared by treating the benzoylated sugar with dibutyltin oxide.