Very frustrating day in the lab today. I'm making threonolactone (5-mem lactone with a 2,3 trans diol) from ascorbic acid with basic aqueous hydrogen peroxide. Oxalic acid is the major byproduct.
I tried a silica column, but the oxalic acid just streaks through. I tried washing an ethyl acetate solution of threonolactone and oxalic acid with dilute NaOH, but threonolactone is too water soluble and just ended up in the water. I'm going to try recrystallising from water next, but I'd rather not have to fiddle about with water if possible.
Another suggestion was taking the column very slowly and letting the oxalic acid streak away. This will use a hell of alot of solvent (and time) though, so I'm not overly keen on that idea.
Does anyone have any experience with oxalic acid, or any ideas?
edit: another idea I had was to destroy the oxalic acid with an oxidising agent that will leave my hydroxyls alone, or at least will only oxidise them very slowly. Iodine perhaps?