5-bromo-3-fluoro-N-methoxy-N-methylpyridine-2-carboxamide → 5-Bromo-3-fluoropyridine-2-carbaldehyde

Temperature

16 °C

5-Bromo-3-fluoro-N-methoxy-N-methylpicolinamide (0.63 g, 2.4 mmol) was stirred in THF (12 mL) at 60° C. Diisobutylaluminium hydride (1 M in THF, 2.8 mL, 2.8 mmol) was added dropwise and the reaction mixture stirred below 50° C. for 2 h. Further diisobutylaluminium hydride (1 M in THF, 0.85 mL, 0.85 mmol) was added and the reaction mixture allowed to warm to 16° C. over 2 h. Rochelles salt solution (sat. aq.) was added and the aqueous phase extracted with EtOAc. The combined organics were dried (MgSO4), filtered and concentrated in vacuo. The residue was purified by column chromatography using silica gel and eluting with 10-70% EtOAc in isohexanes to afford 5-bromo-3-fluoropicolinaldehyde.

1. additionRochelles salt solution (sat. aq.) was added
2. extractionthe aqueous phase extracted with EtOAc
3. dry with materialThe combined organics were dried (MgSO4)
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. customThe residue was purified by column chromatography
7. washeluting with 10-70% EtOAc in isohexanes

ORD record

ord-d47cf5bee76941c2a5330f1b51701cb9

Source dataset

uspto-grants-2015_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08975406B2