反应详情

tert-Butyl 4-(3-acetyl-2-oxo-2H-pyrano[2,3-b]pyridin-7-yl)-1,4-diazepane-1-carboxylate (350 mg, 0.903 mmol) in 10 mL of chloroform was treated with bromine (1M in CHCl3, 0.9 mmol) at room temperature. The reaction mixture was stirred at room temperature for 16 hours. The precipitated solid was filtered and the mother liquor was concentrated. The residue was purified on silica gel to yield tert-butyl 4-(3-(2-bromoacetyl)-2-oxo-2H-pyrano[2,3-b]pyridin-7-yl)-1,4-diazepane-1-carboxylate (132.2 mg, 32%). MS m/z 489 [M+Na]+.

1. filtrationThe precipitated solid was filtered
2. concentrationthe mother liquor was concentrated
3. customThe residue was purified on silica gel