反应详情

To a stirring solution of 4-Bromo-3-methoxy-indazole-1-carboxylic acid ethyl ester CLXXXV (1.27 g, 4.14 mmol) in THF (28 ml) and H2O (9 ml) was added LiOH (397 mg, 16.6 mmol). The reaction mixture was stirred at reflux for 2 hours then at room temperature for 15 hours. The mixture was concentrated. The residue was diluted with EtOAc (50 ml), washed with HCl (1M) and brine, dried over MgSO4, filtered and concentrated affording 4-Bromo-3-methoxy-1H-indazole CLXXXVI as an off-white solid (98% yield), which was used without further purification in the next step.

1. temperatureat reflux for 2 hours
2. concentrationThe mixture was concentrated
3. additionThe residue was diluted with EtOAc (50 ml)
4. washwashed with HCl (1M) and brine
5. dry with materialdried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated