Synthesis
The general procedure for the synthesis of 5-bromo-2-iodoaniline from 4-bromo-1-iodo-2-nitrobenzene was as follows: 4-bromo-1-iodo-2-nitrobenzene (8.38 g, 109.6 mmol) was dissolved in a mixed solvent of acetic acid (AcOH, 45 mL) and ethanol (EtOH, 45 mL) at room temperature, followed by the addition of powdered iron (Fe, 6.12 g 109.6 mmol). The reaction mixture was heated to 100 °C and stirred for 1.3 h, after which it was cooled to room temperature. The reaction mixture was diluted with ether (Et2O, 90 mL) and washed with saturated aqueous sodium bicarbonate (NaHCO3) solution (200 mL). The organic layer was separated and the aqueous layer was further extracted with ether (3 x 60 mL). All organic layers were combined, washed with brine (300 mL), dried over anhydrous sodium sulfate (Na2SO4) and subsequently concentrated under reduced pressure. The residue was purified by fast column chromatography (silica gel as stationary phase, hexane/ethyl acetate=19:1 as eluent) to afford the target product 5-bromo-2-iodoaniline (6.89 g, 91% yield) as a light yellow solid.
References
[1] Heterocycles, 2009, vol. 79, # C, p. 805 - 820
[2] Tetrahedron, 2013, vol. 69, # 45, p. 9481 - 9493
[3] Synthesis, 2008, # 13, p. 2039 - 2044
[4] Chemical & Pharmaceutical Bulletin, 1987, vol. 35, # 5, p. 1823 - 1828
[5] Patent: WO2011/119860, 2011, A1. Location in patent: Page/Page column 90
