Potassium Carbonate → 5-Isopropyl-6-methoxypyridin-3-amine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Argon was bubbled through a slurry of potassium carbonate (4.45 g, 32.2 mmol), potassium isopropenyltrifluoroborate (3.18 g, 21.46 mmol), bis(4-(di-tert-butylphosphino)-N,N-dimethylbenzenamine) palladium dichloride (Aldrich, St. Louis, Mo., 0.152 g, 0.215 mmol), and 3-bromo-2-methoxy-5-nitropyridine (2.50 g, 10.73 mmol) in 50 mL dioxane and 20 mL water for 5 min. The reaction was sealed and heated to 80° C. for 1 h. The dark red reaction was cooled and partitioned between water and DCM. The aqueous layer was extracted with DCM 3 times, and the combined organics were dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo, to give a red solid, which was used without further purification. The solid was treated 10% palladium on carbon (50% water wet) (2.62 g, 2.464 mmol) and 75 mL MeOH and was fitted with hydrogen balloon and stirred rapidly for 3 h. The reaction was flushed with nitrogen, filtered through Celite® (diatomaceous earth), rinsing with 400 mL MeOH, and concentrated in vacuo to give 5-isopropyl-6-methoxypyridin-3-amine (1.81 g, 10.89 mmol, quantitative yield) as a brown oil. m/z (ESI, +ve ion) 167 (M+H)+. 1H NMR (400 MHz, CDCl3) δ 7.51 (d, J=2.9 Hz, 1H), 6.94 (d, J=2.7 Hz, 1H), 3.90 (s, 3H), 3.13 (m, 1H), 1.14-1.22 (m, 6H).

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