Stereospecific synthesis of α- and β-C-aryl-Δ 2 -glycopyranosides from p-tert-butylphenyl α-O-Δ 2 -glycopyranoside via Grignard reagents

Palladium-catalysed coupling of p-tert-butylphenyl α-O-Δ2-glycopyranoside with various substituted arylmagnesium bromides provides the corresponding C-α-aryl-Δ2-glycopyranosides, while nickel-mediated reaction allows the preparation of the C-β-aryl anomers.