[OH:1][C:2]1[C:7]([C:8]([O:10][CH2:11][CH3:12])=[O:9])=[C:6]([CH3:13])[C:5]([O:14][S:15]([CH3:18])(=[O:17])=[O:16])=[CH:4][CH:3]=1.[Br:19]N1C(=O)CCC1=O>C(#N)C>[Br:19][C:3]1[C:2]([OH:1])=[C:7]([C:6]([CH3:13])=[C:5]([O:14][S:15]([CH3:18])(=[O:17])=[O:16])[CH:4]=1)[C:8]([O:10][CH2:11][CH3:12])=[O:9]To a solution of ethyl 6-hydroxy-2-methyl-3-((methylsulfonyl)oxy)benzoate (116c, 1.3 g, 4.8 mmol) in acetonitrile (63 mL) was added N-bromosuccinimide (1.1 g, 6.2 mmol). The reaction was stirred at room temperature for 20 hours. The reaction mixture was concentrated under vacuum then diluted with water (30 mL) and extracted with dichloromethane (2×50 mL). The combined organic layers were washed with brine (30 mL), dried over magnesium sulfate, concentrated under vacuum, and purified by column chromatography (30% EtOAc/Heptane) to give ethyl 3-bromo-2-hydroxy-6-methyl-5-((methylsulfonyl)oxy)benzoate (116d, 1.3 g, 79% yield) as a yellow solid.
読み込み中…