Benzyl Bromide → 2-(benzyloxy)-4-nitroaniline

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Reaction Steps

The starting 2-amino-5-nitrophenol (21.2 g, 0.14 mol) was dissolved in 350 mL THF. Solid potassium t-butoxide (15.85 g, 0.141 mol) was added slowly, with vigorous stirring. Then a solution of benzylbromide (in 150 mL THF) was added slowly and stirred at room temperature for 2 days. The solvent was removed and the crude oil poured into water (ca. 500 mL) and 3:1 ethyl acetate/methylene chloride (ca. 200 mL). The solid precipitate was filtered off and dried, then recrystallized in toluene to give 2-benzyloxy-4-nitro-phenylamine (9.1 g). The aqueous and organic layers were separated and the aqueous layer was extracted twice with 3:1 ethyl acetate/methylene chloride. The combined organic layers were washed with 5% sodium hydroxide (which formed three layers, and the middle layer contained the desired material by TLC), then the desired layer was washed twice with water, then brine, and dried over anhydrous magnesium sulfate, filtered and the solvent removed. The solid was recrystallized in toluene, filtered and dried to yield 12 g of 2-benzyloxy-4-nitro-phenylamine. (The total yield was 62%.). 1H NMR (CDCl3) 7.9-7.7 (m, 2H), 7.5-7.3 (m, 5H), 6.65 (d, 1H, J=8.68 Hz), 5.15 (s, 2H), 4.57 (br, 2H).

Provenance & Evidence