Ammonium Chloride → 7-Bromo-5-fluoroquinoline

A glass microwave reaction vessel was charged with (E)-3-(4-bromo-2-fluoro-6-nitrophenyl)acrylaldehyde (35 mg, 0.128 mmol), iron powder (0.018 mL, 2.55 mmol, Aldrich) and ammonium chloride (6.83 mg, 0.128 mmol, Aldrich) in ethanol (1 mL). The reaction mixture was stirred and heated in an Emrys Optimizer microwave reactor (Personal Chemistry, Biotage AB, Inc., Upssala, Sweden) at 120° C. for 5 min. The mixture was filtered through a pad of Celite® (diatomaceous earth), washed with EtOAc. The solvent was removed in vacuo and the residue was purified by silica gel chromatography eluting with 20% EtOAc/hexanes to give 7-bromo-5-fluoroquinoline (16 mg, 0.071 mmol, 55.4% yield). 1H NMR (300 MHz, CDCl3) δ 7.20-7.34 (m, 1H) 7.59-7.74 (m, 1H) 7.90 (d, J=8.48 Hz, 1H) 8.58 (d, J=1.61 Hz, 1H) 8.95 (d, J=2.34 Hz, 1H). m/z (ESI, +ve ion) 227.9 (M+H)+.