反应详情

To a solution of 6-bromo-4-nitro-1H-indazole (10 g, 41.3 mmol, available from Sinova) in acetonitrile (100 ml) and acetic acid (20.00 ml) was added Selectfluor® (22.10 g, 83 mmol). The resultant mixture was heated to 100° C. and stirred overnight. The resultant orange solution was concentrated under vacuum then partitioned between ethyl acetate and water. The layers were separated and the aqueous extracted again with ethyl acetate. The combined organics were dried over MgSO4, filtered and concentrated. The solid was then dissolved in 20 ml DCM, loaded onto a 330 g silica column and purified on a 0-100% EtOAc/Cyclohexane gradient. The relevant fractions were combined and concentrated to yield the title compound as an orange solid (6.9 g).

1. concentrationThe resultant orange solution was concentrated under vacuum
2. customthen partitioned between ethyl acetate and water
3. customThe layers were separated
4. extractionthe aqueous extracted again with ethyl acetate
5. dry with materialThe combined organics were dried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated
8. dissolutionThe solid was then dissolved in 20 ml DCM
9. custompurified on a 0-100% EtOAc/Cyclohexane gradient
10. concentrationconcentrated