反应详情

To a cold (0-10° C.) solution of methyl 5-tert-butyl-3-nitropyrrole-2-carboxylate (0.100 g, 0.44 mmol), benzyltributylammonium bromide (0.16 mg, 0.44 mmol, 1 equiv), and dimethyl sulfate (46 μL, 0.49 mmol, 1.1 equiv) in CH2Cl2 (1 mL) was added a 50% NaOH solution (0.21 g, 2.65 mmol, 6 equiv). After 5 min, the cooling bath was removed and the mixture was stirred at room temp. for 4 h. The reaction mixture was diluted with CH2Cl2, washed with water and a 10% NH4OAc solution (2x), dried (Na2SO4), and concentrated under reduced pressure to give a bright yellow oil. The oil was purified by flash chromatography (70% CH2Cl2/hexane) to give methyl 5-tert-butyl-1-methyl-3-nitropyrrole-2-carboxylate as a pale yellow oil which solidifies upon standing (0.061 g, 62%): 1H NMR (CDCl3) δ1.38 (s, 9H)., 3.80 (s, 3H), 3.92 (s, 3H), 6.47 (s, 1H).

1. customthe cooling bath was removed
2. additionThe reaction mixture was diluted with CH2Cl2
3. washwashed with water
4. dry with materiala 10% NH4OAc solution (2x), dried (Na2SO4)
5. concentrationconcentrated under reduced pressure
6. customto give a bright yellow oil
7. customThe oil was purified by flash chromatography (70% CH2Cl2/hexane)