Direct vinylation of glucose derivatives with acetylene

Vinyl ethers, promising chiral carbohydrate synthons, have been synthesized by the addition of glucose acetals (1,2:5,6-di-O-isopropylidene-α-d-glucofuranose, methyl 4,6-O-benzylidene-α-d-glucopyranoside, 1,2-O-cyclohexylidene-α-d-glucofuranose, methyl α-d-glucopyranoside) to acetylene under atmospheric and elevated pressures in an autoclave in the presence of superbase catalytic systems (KOH-DMSO, t-BuOK-DMSO). The complete vinylation of 1,2:5,6-di-O-isopropylidene-α-d-glucofuranose and methyl α-d-glucopyranoside has been realized under elevated pressure of acetylene in the system KOH-THF as well.