反应详情

A solution of tert-butyl (2,4-difluoro-3-(quinoxaline-6-carbonyl)phenyl) carbonate (1.06 g, 2.7 mmol, 1.0 eq.) in HCl/dioxane (2.5 N, 50 mL) was stirred at rt overnight, then concentrated. The residue was suspended in NaHCO3 solution, extracted with EA (10 mL×3). The combined organic layers were dried over anhydrous Na2SO4 and concentrated. The residue was purified via flash column chromatography (PE/EA=2/1,v/v) to afford (2,6-difluoro-3-hydroxyphenyl) (quinoxalin-6-yl)methanone as a brown solid (600 mg, 77.7%). LRMS (M−H+) m/z calculated 285.1, found 285.0. 1H NMR (DMSO-d6, 400 MHz) δ 10.34 (s, 1 H), 9.09-9.12 (dd, 2 H), 8.39 (s, 1 H), 8.31-8.31 (d, 1 H), 7.14-7.27 (m, 2 H).

1. concentrationconcentrated
2. extractionextracted with EA (10 mL×3)
3. dry with materialThe combined organic layers were dried over anhydrous Na2SO4
4. concentrationconcentrated
5. customThe residue was purified via flash column chromatography (PE/EA=2/1,v/v)