Sulfuric Acid → 2-Tert-butyl-5-nitroaniline

Participants

Reaction Steps

To H2SO4 (50.0 g, 509.79 mmol) was slowly added 2-tert-Butylaniline (5.0 g, 33.50 mmol). The mixture was stirred at room temperature until it became Homogeneous, then was cooled to −10° C. before slow addition of KNO3 in small portions (5.00 g, 49.45 mmol) via a powder addition funnel. After stirring at −10° C. for an hour, the reaction mixture was poured over a small portion of ice in a 250 mL beaker, allowed to stand for 10 min, then filtered and discarded white precipitate. The aqueous solution was neutralized with NH4OH until pH 8–9 (Litmus pH paper) and partitioned between EtOAc/water. The organic phase was washed with water, and saturated NaCl solutions, dried over anhydrous Na2SO4 and evaporated to a dryness (brown oil). The brown residue was recrystallized from methanol/water to give the desired compound (4.1 g, 63%) as dark brown crystals. TLC (20% EtOAc/Hexane) Rf=0.66; 1HNMR (CDCl3) δ 7.55 (dd, J=8.4, 2.4 Hz, 1H), 7.46 (d, J=2.7 Hz, 1H), 7.35–7.33 (d, J=8.7 Hz), 4.16 (br.s, 2H), 1.44 (s, 9H).

Provenance & Evidence