反应详情

A mixture of 4-bromo-6-methyl-1H-indazole (1.05 g, 5 mmol), DHP (2.1 g, 25 mmol), and TsOH.H2O (96 mg, 0.5 mmol) in THF (50 ml) under nitrogen was heated at reflux overnight. The reaction mixture was concentrated in vacuo and to the residue was added DCM (300 mL) and water (50 mL). The organic layer was dried over MgSO4, filtered, and concentrated in vacuo. The residue was purified by silica gel chromatography by using petroleum ether:EtOAc (100:1) as eluting solvents to afford 4-bromo-6-methyl-1-(tetrahydro-2H-pyran-2-yl)-1H-indazole as light yellow oil (1.1 g, 90%) MS (ESI): m/z=295.1 [M+1]+.

1. temperaturewas heated
2. temperatureat reflux overnight
3. concentrationThe reaction mixture was concentrated in vacuo and to the residue
4. additionwas added DCM (300 mL) and water (50 mL)
5. dry with materialThe organic layer was dried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customThe residue was purified by silica gel chromatography
9. washas eluting solvents