تفاعل #1144316

معادلة التفاعل

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

المذيبات

dichloromethane

ظروف التفاعل

المعالجة

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

الإجراء التجريبي

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).

المصدر