反应详情

Under an argon atmosphere, to a suspension of N-(2-benzyl-8-methoxybenzo[f]quinoxalin-3-yl)acetamide (60.0 mg, 168 μmol) in anhydrous dichloromethane (2 mL) was added boron trifluoride (1.0 M in dichloromethane) (840 μL, 840 μmol) at 0° C. After elevating to room temperature, the mixture was stirred for 3 hours. To the mixture was then added a solution of saturated sodium hydrogencarbonate, and 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. Filtration and concentration under reduced pressure gave N-(2-benzyl-8-hydroxybenzo[f]quinoxalin-3-yl)acetamide (13) as a crude yellow solid product. The product was used for the subsequent reaction without any further purification. TLC Rf=0.36 (n-hexane/ethyl acetate=1/2); 1H NMR (500 MHz, CD3OD) δ 2.17 (s, 3H), 4.50 (s, 2H), 7.20-7.32 (m, 9H), 7.78 (d, 1H, J=9.0 Hz), 7.96 (d, 1H, J=9.0 Hz), 9.44 (d, 1H, J=7.5 Hz).

1. customAfter elevating to room temperature
2. extractionthe product was extracted with ethyl acetate (×3)
3. extractionThe combined organic extract
4. washwas washed successively with water (×1) and brine (×1)
5. dry with materialby drying over anhydrous sodium sulfate
6. filtrationFiltration and concentration under reduced pressure