Реакция #1144316

Уравнение реакции

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

Растворители

dichloromethane

Условия реакции

Обработка

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

Методика

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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