反应详情

温度

190 °C

A mixture of 3-amino-2-benzyl-8-methoxybenzo[f]quinoxaline (12) (125 mg, 396 μmol) and pyridinium hydrochloride (2.50 g, 21.6 mmol) was stirred at 190° C. (oil bath temperature) for 30 minutes and at 210° C. (oil bath temperature) for further 30 minutes. After cooling to room temperature, to the mixture was added water, the product was extracted with ethyl acetate (×3). The combined organic extract was washed successively with water (×1) and brine (×1), followed by drying over anhydrous sodium sulfate. After filtration and concentration under reduced pressure, the residue was purified by silica gel flash column chromatography (n-hexane/ethyl acetate=1/1→1/10) to give 3-amino-2-benzylbenzo[f]quinoxalin-8-ol (14, v-coelenteramine) (55.5 mg, 184 μmol, 46.5%) as an ocherous solid.

1. waitat 210° C. (oil bath temperature) for further 30 minutes
2. temperatureAfter cooling to room temperature, to the mixture
3. extractionthe product was extracted with ethyl acetate (×3)
4. extractionThe combined organic extract
5. washwas washed successively with water (×1) and brine (×1)
6. dry with materialby drying over anhydrous sodium sulfate
7. filtrationAfter filtration and concentration under reduced pressure
8. customthe residue was purified by silica gel flash column chromatography (n-hexane/ethyl acetate=1/1→1/10)