反应详情

温度

0 °C

To a solution of 2-ethyl-6-methyl-isonicotinamide (2.85 g, 17.4 mmol) and pyridine (6.74 g, 85.2 mmol) in DCM (80 mL), trifluoroacetic anhydride (9.11 g, 43.4 mmol) is added dropwise at 0° C. The mixture is stirred at 0° C. for 1 h before it is carefully diluted with water and DCM. The mixture is washed with 4% aq. citric acid solution followed by sat. aq. NaHCO3-solution. The washings are extracted twice with DCM. The combined org. extracts are dried over MgSO4, filtered and concentrated and briefly dried under HV to give 2-ethyl-4-cyano-6-methyl-pyridine (2.65 g) as a colourless liquid; LC-MS: tR=0.58 min, [M+1]+=147.06; 1H NMR (CDCl3): δ 1.33 (t, J=7.5 Hz, 3H), 2.61 (s, 3H), 2.86 (q, J=7.8 Hz, 2H), 7.21 (s, 2H).

1. washThe mixture is washed with 4% aq. citric acid solution
2. extractionThe washings are extracted twice with DCM
3. dry with materialextracts are dried over MgSO4
4. filtrationfiltered
5. concentrationconcentrated
6. custombriefly dried under HV