1. Weigh 1.0 g of a 50% aqueous glutaraldehyde solution into a 50 ml round bottom flask.
2. Add 5.0 ml of 0.5N HCI.
3. Add 0.5 g methylamine hydrochloride. (Reagent 2).
4. Add 0.83 g acetone dicarboxylic Acid. (Reagent 3).
5. Add 2 ml of an aqueous solution containing 0.36 g disodium hydrogen phosphate and 0.11 g
KOH (Reagent 4). Measure the pH.
6. Attach a water cooled reflux condenser, and heat at reflux for 20 min. Again measure the
7. Add 10 drops (0.33ml) of conc. hydrochloric acid and continue reflux for 10 min. Again
measure the pH.
8. Cool to room temperature, then add 1 ml of a solution prepared by dissolving 11 9 KOH in
10 ml H20 (Reagent 5).
9. Cool to room temperature, then extract 4 times with 8 ml portions of DCM in a large test-
10. Wash the combined extracts with saturated NaHCOs, then with brine (saturated NaCI).
Check the pH of the last aqueous layer.
11. Dry the combined organic extracts with NazSOs.
12. Decant into a 50 ml beaker containing a boiling stone. Evaporate NEARLY to dryness on a
hot plate, then completely to dryness, without heating using a gentle stream of air.
13. The product can be purified from the gummy residue by washing twice with 8 ml of boiling
hexane. Filter the combined extracts into a tared 20 ml scintillation vial, then evaporate to
dryness as in step 11.
14. Dissolve a small amount (tip of a spatula) in a few ml of CH2Cle and apply to an IR card for