反应详情

To a stirred suspension of 3-chloro-6,7-dimethyl-quinoxalin-2-ylamine (30.9 g, 0.16 mol) in water/THF 1:1 (540 mL) at room temperature was added bromoacetaldehyde diethyl acetal (94.6 g, 0.48 mol) and 5 g of PPTS in one portion. After stirring at room temperature for 1 h, the mixture was heated to reflux for 3 h under stirring and then stirred for an additional 15 h at room temperature. The pH value of the mixture was adjusted to pH 8 by addition of solid sodium carbonate. The precipitate formed was filtered off to give 25 g of the title compound. 1H-NMR (300 MHz, d6-DMSO): δ=8.85 (1H, s), 8.19 (1H, s), 7.73 (1H, bs), 7.80 (1H, bs), 3.60 (6H, s) ppm.

1. temperaturethe mixture was heated
2. temperatureto reflux for 3 h
3. stirringunder stirring
4. stirringstirred for an additional 15 h at room temperature
5. customThe precipitate formed
6. filtrationwas filtered off