Methyl formate → 3,5-Dibromo-4-pyridinecarboxaldehyde

Temperature

0 °C

A solution of diusopropylamine (6.6 mL, 46.43 mmol) in THF (40 mL) at 0° C. was treated with n-butyllithium in hexanes (2.50 M solution, 18.6 mL, 46.43 mmol) over 15 minutes, stirred at 0° C. for 30 minutes, diluted with THF (200 mL), cooled to −78° C., treated with 3,5-dibromopyridine (10 g, 42.21 mmol) in THF (110 mL) over 95 minutes, stirred at −78° C. for 30 minutes, treated dropwise with methylformate (5.2 mL, 84.42 nunol), stirred at −78° C. for 2 hours, transferred to ice-cold saturated NaHCO3 solution, stirred for 15 minutes, and extracted with diethyl ether. The extract was washed with brine, dried (MgSO4), filtered, and concentrated. The residue was purified by flash chromatography on silica gel with 10% acetone/hexane to provide the title compound.

1. temperaturecooled to −78° C.
2. stirringstirred at −78° C. for 30 minutes
3. stirringstirred at −78° C. for 2 hours
4. stirringstirred for 15 minutes
5. extractionextracted with diethyl ether
6. washThe extract was washed with brine
7. dry with materialdried (MgSO4)
8. filtrationfiltered
9. concentrationconcentrated
10. customThe residue was purified by flash chromatography on silica gel with 10% acetone/hexane

ORD record

ord-177784ba817140fe9107c42de82581b9

Source dataset

uspto-grants-2003_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06579882B2