反応 #71394

反応方程式

SelectFluor

5-bromo-8-(3,5-dimethoxy-phenyl)-quinoxaline

→

5-bromo-8-(2-fluoro-3,5-dimethoxy-phenyl)-quinoxaline

溶媒

CH3CN

反応条件

後処理

1. 1
   その他quenched by addition of H2O
2. 2
   濃縮concentrated
3. 3
   その他to remove CH3CN
4. 4
   workup.ADDITIONThe resulting mixture was diluted with EtOAc/H2O
5. 5
   ろ過filtered
6. 6
   その他to provide a white solid (batch 1)
7. 7
   抽出The filtrate was extracted with EtOAc
8. 8
   洗浄The organic phase was washed with H2O and brine
9. 9
   乾燥dried (Na2SO4)
10. 10
    ろ過filtered
11. 11
    濃縮concentrated
12. 12
    その他to afford batch 2
13. 13
    その他purified by silica gel MPLC (Hex/EtOAc, 7:3)

実験手順

SelectFluor (20.5 g, 58 mmol, 2 equiv) was added portionwise to a solution of 5-bromo-8-(3,5-dimethoxy-phenyl)-quinoxaline (Step 1.4) (10 g, 29 mmol) in CH3CN (300 mL) at rt. The reaction mixture was stirred at rt for 0.5 h, quenched by addition of H2O and concentrated to remove CH3CN. The resulting mixture was diluted with EtOAc/H2O and filtered to provide a white solid (batch 1). The filtrate was extracted with EtOAc. The organic phase was washed with H2O and brine, dried (Na2SO4), filtered and concentrated to afford batch 2. The two batches were combined and purified by silica gel MPLC (Hex/EtOAc, 7:3) to afford a sample of 5-bromo-8-(2-fluoro-3,5-dimethoxy-phenyl)-quinoxaline (Step 94.3) and a sample of the title compound which was further purified by trituration in EtOAc to provide 2.28 g of a white solid. Title compound: ESI-MS: 381.0/382.9 [M+H]+; tR=4.92 min (System 1); TLC: Rf=0.26 (Hex/EtOAc, 7:3).

出典