Sodium hydride → Methyl 1-amino-4-bromo-1H-pyrrole-2-carboxylate
反応式
[CH3:1][O:2][C:3]([C:5]1[NH:6][CH:7]=[C:8]([Br:10])[CH:9]=1)=[O:4].[H-].[Na+].[NH4+:13].[Cl-]>CN(C=O)C>[CH3:1][O:2][C:3]([C:5]1[N:6]([NH2:13])[CH:7]=[C:8]([Br:10])[CH:9]=1)=[O:4][CH3:1][O:2][C:3]([C:5]1[NH:6][CH:7]=[C:8]([Br:10])[CH:9]=1)=[O:4].[H-].[Na+].[NH4+:13].[Cl-]>CN(C=O)C>[CH3:1][O:2][C:3]([C:5]1[N:6]([NH2:13])[CH:7]=[C:8]([Br:10])[CH:9]=1)=[O:4]To a solution of 4-bromo-1H-pyrrole-2-carboxylic acid methyl ester (3.5 g, 17.2 mmol, 1 eq) in DMF (120 mL) was added NaH (0.82 g, 20.6 mmol, 1.2 eq) at 0° C., and the mixture was stirred at 0° C. for 1 h, followed by the addition of o-(diphenylphosphinyl)-hydroxylamine (6 g, 25.8 mmol). The reaction mixture was stirred for another 1 h, then neutralized with 20% NH4Cl solution, and extracted with EA. The combined organic layers were washed with water and brine, dried over sodium sulfate, filtered, and concentrated by evaporation. The residue was purified by column chromatography on silica gel (PE/EA=4:1) to give 1-amino-4-bromo-1H-pyrrole-2-carboxylic acid methyl ester (2.9 g, yield 77%) as a light yellow solid. MS (ES+) requires: 218, 220. found 219, 221 [M+H]+; purity: 97%.
読み込み中…
