反应详情

To a solution of methyl 4-(2-amino-5-nitrophenyl)-2,2-dimethylbut-3-ynoate (260 mg, 1.0 mmol) and pyridine (160 mg, 2.0 mol) in CH2Cl2 (20 mL) was added butyryl chloride (140 mg, 1.3 mmol) at 0° C. The reaction mixture was warmed to room temperature and stirred for 3 h before the mixture was poured into ice-water. The organic layer was separated and the aqueous phase was extracted with CH2Cl2 (30 mL×3). The combined organic layers were dried over anhydrous Na2SO4 and evaporated under reduced pressure to obtain methyl 4-(2-butyramido-5-nitrophenyl)-2,2-dimethylbut-3-ynoate (150 mg, 45%), which was used directly in the next step. 1H NMR (400 MHz, CDCl3) δ 8.79 (brs, 1H), 8.71 (d, J=9.2 Hz, 1H), 8.24 (d, J=2.8 Hz, 1H), 8.17 (dd, J=2.8, 9.2 Hz, 1H), 3.82 (s, 3H), 2.55 (t, J=7.2 Hz, 2H), 1.85-1.75 (m, 2H), 1.63 (s, 6H), 1.06 (t, J=6.8 Hz, 3H).

1. customThe organic layer was separated
2. extractionthe aqueous phase was extracted with CH2Cl2 (30 mL×3)
3. dry with materialThe combined organic layers were dried over anhydrous Na2SO4
4. customevaporated under reduced pressure