反応 #70513

反応方程式

sodium bicarbonate

6-bromo-4-nitro-1H-indazole

3,4-dihydropyran

pyridinium para-toluene sulfonate

→

title compound

6-Bromo-4-nitro-2-(tetrahydro-2H-pyran-2-yl)-2H-indazole

溶媒

dichloromethane

反応条件

後処理

1. 1
   温度was heated
2. 2
   温度at reflux for 4.5 hours
3. 3
   その他The layers were separated
4. 4
   抽出the aqueous layer extracted with dichloromethane (2×100 ml)
5. 5
   洗浄The combined organic layers were washed with 5% aqueous citric acid (w/v, 100 ml) and brine (100 ml)
6. 6
   乾燥then dried over magnesium sulphate
7. 7
   その他Solvent was removed in vacuo

実験手順

A mixture of 6-bromo-4-nitro-1H-indazole (10.0 g, 0.041 mol), 3,4-dihydropyran (8.52 ml, 0.09 mol) and pyridinium para-toluene sulfonate (125 mg, 0.50 mol) in dichloromethane (150 ml) was heated at reflux for 4.5 hours. The reaction was allowed to cool to room temperature and was poured onto saturated aqueous sodium bicarbonate (200 ml). The layers were separated and the aqueous layer extracted with dichloromethane (2×100 ml). The combined organic layers were washed with 5% aqueous citric acid (w/v, 100 ml) and brine (100 ml) then dried over magnesium sulphate. Solvent was removed in vacuo to give the title compound which was used in subsequent reactions without further purification (12.89 g).

出典