반응 #1144316

반응 방정식

NaHCO3

5-bromo-7-fluoro-1H-indazole

3,4-dihydro-2H-pyran

p-TsOH

→

5-bromo-7-fluoro-1-(tetrahydro-2H-pyran-2-yl)-1H-indazole

용매

dichloromethane

반응 조건

후처리

1. 1
   기타The organic layer was separated
2. 2
   건조dried over Na2SO4
3. 3
   농축concentrated in vacuo
4. 4
   기타The residue was purified by column chromatography on silica gel (0˜10% EtOAc in petroleum ether)

실험 절차

To a mixture of 5-bromo-7-fluoro-1H-indazole (9.3 g, 43.26 mmol) and 3,4-dihydro-2H-pyran (4.36 g, 51.9 mmol) in dry dichloromethane (100 mL), was added p-TsOH (424 mg, 2.16 mmol) at room temperature. The resulting mixture was stirred overnight. Work-up: saturated aqueous NaHCO3 (30 mL) was slowly added to the reaction mixture. The organic layer was separated, dried over Na2SO4, and concentrated in vacuo. The residue was purified by column chromatography on silica gel (0˜10% EtOAc in petroleum ether) to give 5-bromo-7-fluoro-1-(tetrahydro-2H-pyran-2-yl)-1H-indazole as a light yellow solid. (7.8 g). 1H NMR (300 MHz, CDCl3): δ 7.98 (s, 1H), 7.64 (s, 1H), 7.22 (dd, 1H), 5.84 (dd, 1H), 4.07-4.02 (m, 1H), 3.78-3.71 (m, 1H), 2.62-2.53 (m, 1H), 2.16-2.07 (m, 2H), 1.79-1.71 (m, 2H), 1.63-1.33 (m, 1H).

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