Sodium Carbonate → 2-(tert-Butyl)-6-nitroindoline

Participants

Reaction Steps

To a solution of 2-tert-butylindoline (9.7 g) in H2SO4(98%, 80 mL) was slowly added KNO3(5.6 g, 56 mmol) at 0° C. After addition, the reaction mixture was stirred at room temperature for 1 h. The mixture was carefully poured into cracked ice, basified with Na2CO3 to pH 8 and extracted with ethyl acetate. The combined extracts were washed with brine, dried over anhydrous Na2SO4 and concentrated under vacuum. The residue was purified by column chromatography to give 2-tert-butyl-6-nitroindoline (4.0 g, 31% over two steps). 1 H NMR (300 MHz, CDCl3) δ 7.52(dd, J=1.8, 8.1 Hz, 1 H), 7.30(s, 1 H), 7.08(d, J=7.8 Hz, 1 H), 3.76(t, J=9.6 Hz, 1 H), 2.98-3.07(m, 1 H), 2.82-2.91(m, 1 H), 0.91(s, 9 H).

Provenance & Evidence