Hydrochloric Acid → N-(4-Formyl-pyridin-3-yl)-2,2-dimethyl-propionamide

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of 2,2-dimethyl-N-(3-pyridinyl)propanamide (3.56 gm, 20 mmol) (prepared as described in J. Org. Chem. 48, 3401 (1983)) in anhydrous tetrahydrofuran (40 mL) was cooled to −70° C. and a solution of 2.5 M n-butyl lithium/hexane (20 mL, 50 mmol) was added dropwise maintaining the temperature at −70° C. This reaction was slowly warmed to −5° C. giving a copious precipitate. This mixture was cooled to −70° C. and dry dimethyl formamide (4.64 mL, 60 mmol) was added. The reaction was allowed to warm to room temperature giving a clear yellow solution. This reaction was poured into 8 N aqueous HCl (16 mL) and ice. After stirring for 10 minutes the pH of the solution was adjusted to 7 and extracted with diethyl ether. The organic layer was dried (Na2SO4), filtered and the solvent evaporated. The residue was purified by column chromatography eluting with 30-100% ethyl acetate/hexane. The appropriate fractions were combined and the solvent removed in vacuo to give the title compound as a solid. 1H-NMR (500 MHz, CDCl3): δ 10.92 (1H, br s), 10.15 (1H, s), 10.05 (1H, s), 8.62 (2H, d, J=4.9 Hz), 7.56 (1H, d, J=4.9 Hz),), 1.39 (9H, s). m/e (m+1): 235.3.

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