反应详情

To a mixture of potassium nitrate (4.80 g, 47.4 mmol) in concentrated sulphuric acid (20 mL) was added portion-wise at 0° C. 2-ethoxy-4-nitrobenzoic acid (4.00 g, 19.0 mmol). The mixture was stirred at 0° C.-r.t. for 3 h, then poured onto ice (120 mL) and stirred for a further 1 h. The precipitate formed was collected by filtration, washing with water, and dried through azeotrope with toluene to give the title compound (4.28 g) as a white solid. 1H NMR (300 MHz, DMSO-d6) δ 8.50 (s, 1H), 7.95 (s, 1H), 4.35 (q, 2H), 1.35 (t, 3H).

1. additionwas added portion-wise at 0° C
2. additionpoured onto ice (120 mL)
3. stirringstirred for a further 1 h
4. customThe precipitate formed
5. filtrationwas collected by filtration
6. washwashing with water
7. dry with materialdried through azeotrope with toluene