Dimethylformamide → HCID 178434286, compound

Temperature

-78 °C

To an Argon flushed flask of anhydrous THF (81 mL) cooled to −78° C. was added a 1.7M solution of tert-butyllithium in n-pentane (27 mL, 45.6 mmol). After stirring the solution at −78° C. for 15 minutes, a solution of 5-Bromo-3-methyl-1H-indazole (3 g, 14.2 mmol) in THF (42 mL) was added dropwise such that the temperature of the solution did not exceed −70° C. After stirring the solution at −78° C. for 30 minutes, anhydrous DMF (3.15 g, 43.09 mmol) was added dropwise. The reaction mixture was then stirred at −78° C. for 30 minutes, warmed to room temperature and stirred for 1.5 hours. The reaction mixture was cooled down to 0° C. and it was added carefully water (36 mL) and ethyl acetate. The ethyl acetate layer was washed with brine, dried over Na2SO4, filtered, and the solvent evaporated in vacuo. The residue was purified by flash column chromatography on silica gel (heptane/EtOAc 6:4 v/v) to afford white solid (1.6 g, 70%).

1. customdid not exceed −70° C
2. stirringAfter stirring the solution at −78° C. for 30 minutes
3. stirringThe reaction mixture was then stirred at −78° C. for 30 minutes
4. temperaturewarmed to room temperature
5. stirringstirred for 1.5 hours
6. temperatureThe reaction mixture was cooled down to 0° C.
7. washThe ethyl acetate layer was washed with brine
8. dry with materialdried over Na2SO4
9. filtrationfiltered
10. customthe solvent evaporated in vacuo
11. customThe residue was purified by flash column chromatography on silica gel (heptane/EtOAc 6:4 v/v)

ORD record

ord-32aa13a18478467999b3bacb69726615

Source dataset

uspto-grants-2012_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08263781B2