反应详情

A solution of 1-[7-(cyclopentylamino)-2-(4-methoxyphenyl)pyrazolo[1,5-a]pyridin-3-yl]ethanone (5.56 g, 15.9 mmol) in N,N-dimethylformamide dimethyl acetal (25 mL) was heated at reflux for 5 days. The mixture was allowed to cool to room temperature. Water was added and the resulting mixture was extracted with ethyl acetate. The organic phase was dried (magnesium sulfate), filtered and concentrated. The resulting residue was purified by flash chromatography (7:3 ethyl acetate:acetone) to give (2E)-1-[7-(cyclopentylamino)-2-(4-methoxyphenyl)pyrazolo[1,5-a]pyridin-3-yl]-3-(dimethylamino)-2-propen-1-one (5.97 g, 93%) as a colored syrup: 1H NMR (CDCl3): δ 7.96–7.59 (m, 3H), 7.53 (d, 1H), 7.23 (dd, 1H), 6.93 (d, 2H), 5.97–5.94 (m, 2H), 5.07 (d, 1H), 3.95 (m, 1H), 3.81 (s, 3H), 3.0–2.3 (b, 6H), 2.07 (m, 2H), 1.76–1.60 (m, 2H); MS m/z 405 (M+1).

1. temperatureat reflux for 5 days
2. extractionthe resulting mixture was extracted with ethyl acetate
3. dry with materialThe organic phase was dried (magnesium sulfate)
4. filtrationfiltered
5. concentrationconcentrated
6. customThe resulting residue was purified by flash chromatography (7:3 ethyl acetate:acetone)