반응 #588453

반응 방정식

Methyl iodide

6-bromoindazole

sodium hydride

→

2-methyl-6-bromoindazole

수율 43.0%

1-methyl-6-bromoindazole

수율 51.0%

용매

THF

반응 조건

후처리

1. 1
   온도cooling
2. 2
   기타The reaction mixture was quenched with ammonium chloride solution
3. 3
   기타the layers were separated
4. 4
   추출The aqueous layer was extracted with ethyl acetate
5. 5
   세척The combined organic layer was washed with brine
6. 6
   건조dried over sodium sulfate
7. 7
   농축concentrated
8. 8
   기타Purification by column chromatography (SiO2, ethyl acetate/hexane gradient)

실험 절차

To 6-bromoindazole (402A) (5.0 g, 25.4 mmol) in THF (50 mL) was added sodium hydride (95%, 672 mg, 26.6 mmol) with ice bath cooling. The mixture was stirred for 30 minutes. Methyl iodide (6.36 mL, 102 mmol) was added at room temperature. The reaction mixture was quenched with ammonium chloride solution and the layers were separated. The aqueous layer was extracted with ethyl acetate. The combined organic layer was washed with brine, dried over sodium sulfate and concentrated. Purification by column chromatography (SiO2, ethyl acetate/hexane gradient) afforded 1-methyl-6-bromoindazole (402B) (2.71 g, 51%) as a yellow oil and 2-methyl-6-bromoindazole (402C) (2.28 g, 43%) as a yellow crystalline solid.

출처