To a refluxing suspension of amide E4 (2.10 g, 5.77 mmol) in 2:1 EtOH:H2O (100 mL) were sequentially added Fe dust (1.29 g, 23.09 mol) and c.HCl (1-2 mL), and the resulting mixture was refluxed for 24 h. After this time, the hot reaction mixture was filtered through a pad of Celite, and solvent was removed under reduced pressure. The resulting residue was crystallized from MeOH:EtOAc to afford amine E5 (in two batches) as a cream-coloured amorphous solid (1.94 g, 90%). 1H NMR [(CD3)2SO]): 2.27 [s, 3H, ArCH3], 6.16 [br s, 2H, ArNH2], 6.75 [d, J=8.36 Hz, 2H, ArNH2], 7.74 [m, 8H, ArH], 9.90 [br s, 1H ArH], 10.55 [br s, 1H, ArNHAr], 12.58 [br s, 1H, ArC(O)NH]. LCMS (APCl+): 335 (100%).
