Dimethylformamide → 5-Bromopyridine-2-carbaldehyde

HRID 1949210Notes

Reaction equation

HRID 1949210 reaction equation
Br[C:2]1[CH:7]=[CH:6][C:5]([Br:8])=[CH:4][N:3]=1.[Li]CCCC.CN([CH:17]=[O:18])C>C1(C)C=CC=CC=1>[Br:8][C:5]1[CH:6]=[CH:7][C:2]([CH:17]=[O:18])=[N:3][CH:4]=1

Participants

5

Conditions

Temperature
-78 °C

Procedure

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).

Workup

  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)

Sources & evidence

ORD record
ord-55980d076c38478b92757de2acb20929
Source dataset
uspto-grants-2013_03
Patent number
US08399660B2

Reaction notes

Loading…