title: The intermolecular migration of polyol stannylenes as a reaction contributing to the regioselectivity of substitution.
abstract: Pairs of the partially protected glycosides benzyl 4,6-O-benzylidene-beta-D-galactopyranoside, benzyl 2,3-di-O-benzyl-beta-D-galactopyranoside, benzyl 2,6-di-O-benzyl-alpha-D-galactopyranoside, and benzyl 2,3-di-O-benzyl-alpha-D-glucopyranoside were treated with equimolar proportions of Bu2SnO in benzene in the conditions of stannylene formation, and the resulting mixture was benzoylated in situ with benzoyl chloride. Estimation of the product of benzoylation led to the following order of reactivity in the stannylenation reaction: 2,3-diol > 4,6-diol, and 2,3-diol > 3,4-diol. An intermolecular migration of dibutyltin between sugars was demonstrated. It is considered that these migrations contribute efficiently to the regiospecificity of the stannylene reaction.
authors.affiliation: Institute de Chimie Moléculaire, Universite de Paris-Sud, Orsay, France. serdavid@icmo.u-psud.fr
authors.forename: S
authors.initials: S
authors.lastname: David
authors.forename: A
authors.initials: A
authors.lastname: Malleron
mesh_terms: D001565:Benzoates / Q000737:chemistry; D006018:Glycols / Q000737:chemistry; D006027:Glycosides / Q000138:chemical synthesis* / Q000737:chemistry; D009947:Organotin Compounds / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D001565:Benzoates; D006018:Glycols; D006027:Glycosides; D009947:Organotin Compounds; C013409:benzoyl chloride