Reaction of anhydro sugars with sodium cobalt tetracarbonyl and carbon monoxide

Abstract

5,6-Anhydro-1,2-O-isopropylidene-α-D-glucofuranose reacts with sodium cobalt tetracarbonyl and carbon monoxide in methanol to afford methyl 6-deoxy-1,2-O-isopropyhdene-α-D-gluco-heptofuranouronate (3) in 82% yield. Treatment of tri-O-acetyl-1,2-anhydro-D-glucopyranose with sodium cobalt tetracarbonyl in ether gives 3,4,6-tri-O-acetyl-D-glucal. The 2,3-anhydro sugars are resistant to cleavage by cobalt tetracarbonyl anion in ether or in methanol. Sugar acetates are de-O-acetylated by treatment with sodium cobalt tetracarbonyl in ether–methanol.