反应详情

Cesium carbonate (15.7 g, 48.2 mmol) and iodomethane (1.50 ml, 24.2 mmol) were added to a solution of imidazo[1,2-a]pyridine-6-carboxylic acid (2.61 g, 16.1 mmol) in DMF (100 ml). The reaction was stirred at ambient temperature overnight, then poured into brine (100 ml) and extracted with ethyl acetate (3×100 mL). The combined organics were washed with saturated sodium bicarbonate solution (25 mL), and a 1N HCl solution (25 mL) then dried over MgSO4 and evaporated to give imidazo[1,2-a]pyridine-6-carboxylic acid methyl ester as a yellow solid (1.1 g, 39%). 1H NMR (250 MHz, CDCl3): δ 8.96 (s, 1H), 7.8-7.6 (m, 4H), 3.98 (s, 3H). MS [EI+] 177 (M+H)+.

1. extractionextracted with ethyl acetate (3×100 mL)
2. washThe combined organics were washed with saturated sodium bicarbonate solution (25 mL)
3. dry with materiala 1N HCl solution (25 mL) then dried over MgSO4
4. customevaporated