Dimethylformamide → 5-Bromopyridine-2-carbaldehyde

Temperature

-78 °C

A solution of 2,5-Dibromo-pyridine (22.2 g, 93.7 mmol, 1.0 equiv.) in toluene (1.2 L) was treated with nBuLi (70.25 ml, 112.4 mmol, 1.2 equiv.) dropwise at −78° C. The resulting solution was stirred at −78° C. for about 30 minutes, and DMF (11 ml, 141 mmol, 1.5 equiv.) was added. The reaction solution was warmed up gradually to RT and then stirred overnight. When TLC and MS showed the reaction was complete, the reaction mixture was concentrated in vacuo, and the residue was directly purified by column chromatography (SiO2, 10-30% EtOAc/Hexanes gradient elution) to afford 5-Bromo-pyridine-2-carbaldehyde (1038, 5.45 g, 31% yield) as yellowish white solid. For 1038: C6H4BrNO, LCMS (EI) m/e 187 (M++H).

1. temperatureThe reaction solution was warmed up gradually to RT
2. stirringstirred overnight
3. concentrationthe reaction mixture was concentrated in vacuo
4. customthe residue was directly purified by column chromatography (SiO2, 10-30% EtOAc/Hexanes gradient elution)

ORD record

ord-1323627035f54fe78eef95d5c980798c

Source dataset

uspto-grants-2014_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08796465B2