反应详情

Sodium hydroxide (1.0 M aqueous solution, 14.6 mL, 14.6 mmol) was added to a solution of 7-(4-bromo-2-chlorophenylamino)-8-chloroimidazo[1,2-a]pyridine-6-carboxylic acid methyl ester (29) in methanol (30 mL) and the solution allowed to stir at room temperature overnight. Methanol was removed by rotary evaporation and the solution diluted with water and acidified to pH 2 by addition of 1.0 M HCl. The aqueous suspension was extracted with 4:1 ethyl acetate/THF. The organic extracts were washed with brine, dried over NaSO4, filtered, and concentrated in vacuo to provide the desired product as a light orange solid (30). MS (APCI+) m/z 400, 402, 404 (M+: Cl, Br pattern) detected. 1H NMR (400 MHz, methanol-d4) δ 9.01 (s, 1H), 7.83 (s, 1H), 7.51 (s, 2H), 7.25 (d, 1H), 6.60 (d, 1H).

1. customMethanol was removed by rotary evaporation
2. additionthe solution diluted with water
3. additionacidified to pH 2 by addition of 1.0 M HCl
4. extractionThe aqueous suspension was extracted with 4:1 ethyl acetate/THF
5. washThe organic extracts were washed with brine
6. dry with materialdried over NaSO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo