反应详情

Dissolve 5.456 g of 1-(6-methoxy-1H-indazol-3-yl)-2-methylpropan-1-one in 100 mL anhydrous DMF. Weigh in 8.96 g cesium carbonate followed by 4.593 g ethyl bromoacetate. The resulting mixture was stirred at room temperature overnight. The solvent was removed under reduced pressure. Partition the residue between EtOAc and water. Extract the aqueous layer with EtOAc several times. The combined organic extract was washed with water (3×) and saturated brine, dried over anhydrous Na2SO4, and evaporated to give the crude product. The title compound was obtained by recrystallization from 40 mL 4:1 hexanes and EtOAc. 1H NMR (CDCl3, 500 MHz) δ 8.26 (d, 8.9 Hz, 1H), 7.00 (dd, 2.1 & 9.0 Hz, 1H), 6.685 (d, 2.1 Hz, 1H), 5.17 (s, 2H), 4.28 (q, 7.1 Hz, 2H), 3.90 (s, 3H), 3.87 (heptet, 6.9 Hz, 1H), 1.29 (t, 7.1 Hz, 3H), 1.28 (d, 6.8 Hz, 6H). LC-MS: 3.51 min. (m/Z=305.1, 327.0).

1. customThe solvent was removed under reduced pressure
2. customPartition the residue between EtOAc and water
3. extractionExtract the aqueous layer with EtOAc several times
4. extractionThe combined organic extract
5. washwas washed with water (3×) and saturated brine
6. dry with materialdried over anhydrous Na2SO4
7. customevaporated
8. customto give the crude product