反応 #77789

反応方程式

HCl

(4-Bromo-5-fluoro-2-iodo-phenyl)-carbamic acid methyl ester

ethinyltrimethylsilane

KOH

→

5-Bromo-6-fluoro-1H-indole

収率 80.0%

溶媒

tert-butanol

triethylamine

反応条件

後処理

1. 1
   温度was refluxed under argon during 20 min
2. 2
   workup.STIRRINGstirred 1 h at room temperature
3. 3
   抽出the mixture extracted three times with EtOAc
4. 4
   洗浄The combined organic layers were washed subsequently with H2O and saturated aqueous NaCl
5. 5
   乾燥dried with MgSO4
6. 6
   その他the solvent was evaporated
7. 7
   その他The crude product obtained
8. 8
   温度the resulting mixture refluxed for 1.5 h
9. 9
   その他The solvent was evaporated
10. 10
    洗浄The organic layer was washed with water
11. 11
    乾燥dried with MgSO4
12. 12
    その他Evaporation of the solvent and column chromatography on silica gel with hexane/EtOAc 9:1

実験手順

A mixture of 70 mg (0.1 mmol) Pd(PPh3)2Cl2 and 27 mg (0.142 mmol) CuI in triethylamine was refluxed under argon during 20 min, cooled to 0° C., treated with 7 g (0.019 mmol) (4-Bromo-5-fluoro-2-iodo-phenyl)-carbamic acid methyl ester, stirred 10 min at room temperature, treated with 2.95 (0.021 mmol) ethinyltrimethylsilane, and stirred 1 h at room temperature. 2M aqueous HCl and ice were added and the mixture extracted three times with EtOAc. The combined organic layers were washed subsequently with H2O and saturated aqueous NaCl, dried with MgSO4 and the solvent was evaporated. The crude product obtained was dissolved in 50 ml tert-butanol, treated with 3.2 g (0.023 mol) KOH and the resulting mixture refluxed for 1.5 h. The solvent was evaporated and the residue distributed between icy water and Et2O. The organic layer was washed with water and dried with MgSO4. Evaporation of the solvent and column chromatography on silica gel with hexane/EtOAc 9:1 gave of 3.2 g (80%) 5-Bromo-6-fluoro-1H-indole, MS: 213 (M, 1Br).

出典