反应详情

The product from Step (1) was dissolved in distilled water (50 ml) by gentle warming and then the resulting solution was filtered. The clear filtrate was cooled in an ice bath and acidified to pH3 with mineral acid. The resulting crystalline precipitate was washed with water and dried to give 1-methyl-3-formyl-4-hydroxy-2(1H)-quinolinone. That the expected product was obtained was confirmed by the spectral data: MS: m/e 203 (M.+); NMR (CDCl3): δ3.6 (s, 3H, NCH3), 10.28 (s, 1H, CHO) ppm.

1. temperatureby gentle warming
2. filtrationthe resulting solution was filtered
3. temperatureThe clear filtrate was cooled in an ice bath
4. washThe resulting crystalline precipitate was washed with water
5. customdried