反応 #71455

反応方程式

SelectFluor

8-(3,5-dimethoxyphenyl)-quinoxaline-5-carboxylic acid ethyl ester

NaHCO3

→

title compound

収率 46.8%

8-(2-Fluoro-3,5-dimethoxy-phenyl)-quinoxaline-5-carboxylic acid ethyl ester

収率 46.8%

溶媒

CH3CN

EtOAc

反応条件

後処理

1. 1
   温度to warm to it over 6 h
2. 2
   その他The aqueous phase was separated
3. 3
   抽出extracted with EtOAc
4. 4
   洗浄The combined organic layers were washed with H2O and brine
5. 5
   乾燥dried (Na2SO4)
6. 6
   ろ過filtered
7. 7
   濃縮concentrated
8. 8
   その他The residue was purified by silica gel column chromatography (Hex/EtOAc, 3:2)

実験手順

SelectFluor (105 mg, 0.30 mmol) was added to a cold (−5° C.) solution of 8-(3,5-dimethoxyphenyl)-quinoxaline-5-carboxylic acid ethyl ester (Step 115.1) (100 mg, 0.30 mmol) in CH3CN (2 mL), under an argon atmosphere. The reaction mixture was allowed to warm to it over 6 h and stirred at that temperature for additional 12 h and diluted in EtOAc and a saturated aqueous solution of NaHCO3. The aqueous phase was separated and extracted with EtOAc. The combined organic layers were washed with H2O and brine, dried (Na2SO4), filtered and concentrated. The residue was purified by silica gel column chromatography (Hex/EtOAc, 3:2) to provide 50 mg of the title compound as an off-white solid. Title compound: ESI-MS: 357.2 [M+H]+; tR=4.58 min (System 1); TLC: Rf=0.24 (Hex/EtOAc, 3:2).

出典