Dimethylformamide → tert-Butyl 4-chloro-3-formylpyridin-2-ylcarbamate

Participants

Reaction Conditions

Reaction Steps

To (4-chloro-pyridin-2-yl)-carbamic acid tert-butyl ester (CB Research and Development Inc., 2.0 g, 8.75 mmol) in THF (18 mL) under nitrogen at −78° C., was added n-BuLi (13.7 mL, 21.9 mmol, 1.6 M in hexanes) dropwise. After stirring at −78° C. for 45 min, a solution of DMF (1.93 mL) in THF (2 mL) was added dropwise. The reaction was stirred at −78° C. for 30 min and was then allowed to warm slowly to room temperature. The reaction was quenched with 1N aq HCl solution and then basified with saturated aqueous sodium bicarbonate solution (50 mL) and extracted with ethyl acetate (3×50 μL). The combined organic extracts were dried over anhydrous Na2SO4 and concentrated in vacuo. The crude product was purified by flash column chromatography on silica gel (EtOAc) to afford the title compound (0.95 g, 42%) as a white solid. 1H NMR (DMSO-d6) δ 10.44 (s, 1H), 10.13 (s, 1H), 8.47 (d, 1H, J=5.2 Hz), 7.40 (d, 1H, J=5.6 Hz), 1.48 (s, 9H).

Provenance & Evidence