Sodium Carbonate → 2-Chloro-4-pyridinecarboxaldehyde

Beteiligte Stoffe

Reaktionsschritte

A suspension of 2-chloro-4-hydroxymethylpyridine (8.0 g, 55.9 mmol), NBS (14.9 g, 83.9 mmol), and K2CO3 (11.75 g, 97.1 mmol) in ethyl acetate was refluxed for 3 h. Another portion of NBS (14.9 g, 83.9 mmol) and Na2CO3 (12.0 g, 114 mmol) was added and heating was continued another 3.5 h. The reaction mixture was cooled, filtered through a pad of celite, concentrated under reduced and chromatographed with 0.5-4% CH3OH/CH2Cl2. The combined fractions were washed with NaHCO3 (sat.), 10% Na2S2O3, and NaCl (sat.), dried, filtered and evaporated to give the title compound as a light yellow solid (5.3 g, 67% yield). 1H NMR (CDCl3): δ 10.06 (s, 1H), 8.66 (d, 1H, J=5.0 Hz), 7.76 (s, 1H), 7.66 (d, 1H, J=5.0 Hz).

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