3-Chloroisonicotinaldehyde

626-60-8

68-12-2

72990-37-5

The general procedure for the synthesis of 3-chloropyridine-4-carbaldehyde from 3-chloropyridine and N,N-dimethylformamide is as follows: 1. add toluene to a 250 mL round-bottomed flask and cool to -78°C. 2. LDA (11 mL, 22.02 mmol) was slowly added dropwise to a solution of 3-chloropyridine (8.80 mmol) in THF (20 mL) at -78°C and stirred at the same temperature for 1 to 2 hours. 3. DMF (822 μL, 10.56 mmol) was added, then the reaction mixture was brought to room temperature and stirred for 1 hour. 4. Ethyl acetate (EA) and water were added to the reaction mixture and the organic and aqueous layers were separated. 5. The organic solvent was further extracted with the aqueous phase and the organic extracts were combined. 6. The combined organic extracts were dried with anhydrous sodium sulfate (Na2SO4), filtered and concentrated in vacuum. 7. The crude product was purified by silica gel column chromatography to afford 3-chloropyridine-4-carbaldehyde (0.33 g, 30-65% yield). 8. The structure of the product was determined by NMR. 8. The structure of the product was confirmed by NMR (400 MHz, CDCl3): δ 7.73 (d, J = 8.0 Hz, 1H), 8.71 (d, J = 4.0 Hz, 1H), 8.81 (s, 1H), 10.52 (s, 1H).