p-Nitro Phenyl Alanine (In House), Succinic Anhydride (CDH); Acetic Acid, Methylene Chloride (Rankem), Iso Propyl Alcohol (Rankem)

p-Nitro phenyl alanine (20g, 0.095mol) was placed in a 500 ml 4-neck rbf then charged with acetic acid (200ml). Succinic anhydride (10.4g, 0.104mol) was added and then heated to 100_{110˚C for 6-8h with continuous stirring. The reaction was monitored by TLC (solvent system: 40% methanol/DCM and 1}2 drops aqueous ammonia). The reaction mixture was cooled to RT, poured slowly onto ice-cold water (500ml) and then poured onto methylene chloride (100ml)in a separating funnel. The organic layer was extracted with DCM and the solvent removed in vacuo. Isopropyl alcohol (50ml) was added to the resultant gum and stirred for 2-3hrs after which the red colored solid product was observed. The product was filtered through a sinter funnel and washed with IPA (2 x 10ml) and dried under vacuum for 4hrs. Yield: 15g (54%).

Rf 0.2 (40% MeOH /DCM). ¹HNMR (300 MHz) in DMSO- d₆: 2.55 (dd, 4H), 2.66 (d, 2H), 4.92 (t, 1H), 7.41 (d, 2H), 8.09 (d, 2H), 12.57(Broad, COOH). MS (ES+) m/z 293.22 and (ES-) m/z 290.97

The Practice of Peptide Synthesis, 2nd edition, M. Bodanszky, A. Bodanszky, 1994, page 17, Springer-Verlag Publications.