Migration of the methylthio group in the solvolysis of some methyl 1-thio-6- O-toluene- p-sulphonyl-β- D-glycopyranosides

Abstract

The hydrolysis and methanolysis of methyl 1-thio-6- O-toluene- p-sulphonyl-β- D-glucopyranoside proceeds with migration of the methylthio group to C-6. Acetolysis of methyl 1-thio-6- O-toluene- p-sulphonyl-β- D-glucopyranoside triacetate and of the corresponding galactoside likewise gives 6- S-methyl-6-thio compounds. The stereo-chemical outcome at C-1 of these reactions is discussed. Replacement of the methylthio group of the methyl 1-thio-6- O-toluene- p-sulphonyl-α- and -β- D-glucopyranosides by an acetoxyl group, using mercuric acetate in acetic acid, proceeds mainly with inversion of configuration at C-1.