L-Fucose was synthesized by deriving L-fucitol to 2:3, 4:5-diisopropylidene-L-fucitol, its oxidation to potassium 2:3, 4:5-diisopropylidene-L-fuconate with potassium permangante, hydrolyzed to L-fuconolactone, and by final reduction with sodium amalgam.