General procedure for the synthesis of 1-(2-bromoethoxy)-2-nitrobenzene from 1,2-dibromoethane and 2-nitrophenol: 1,2-dibromoethane (202.5 g, 1.078 mol), potassium carbonate (K2CO3, 29.8 g, 215.6 mmol) and 2-nitrophenol (15 g, 107.8 mmol) were suspended in 360 mL of acetonitrile. The reaction was refluxed for 2.5 hours. After completion of the reaction, the mixture was cooled to room temperature, filtered and the filtrate was washed with methylene chloride. The filtrate was concentrated, 300 mL of methanol was added and cooled overnight in a refrigerator. The precipitate precipitated was filtered and washed with methanol. The molecular weight of the product 1-(2-bromoethoxy)-2-nitrobenzene was 246.06 g/mol (C8H8BrNO3), and the yield was 21 g in 79.2%.1H-NMR (CDCl3) data: δ 7.84 (dd, 1H), 7.60-7.50 (m, 1H), 7.12-7.02 (m, 2H), 4.42 (t, 2H), 3.67 (t, 2H). 2H), 3.67 (t, 2H).
