Lithium hydroxide, monohydrate → 5-bromo-3-(methylcarbamoyl)-6-(N-methylmethylsulfonamido)benzofuran-2-carboxylic acid
反応式
[Br:1][C:2]1[C:3]([N:19]([CH3:24])[S:20]([CH3:23])(=[O:22])=[O:21])=[CH:4][C:5]2[O:9][C:8]([C:10]([O:12]C)=[O:11])=[C:7]([C:14](=[O:17])[NH:15][CH3:16])[C:6]=2[CH:18]=1.O[Li].O>O1CCOCC1.O>[Br:1][C:2]1[C:3]([N:19]([CH3:24])[S:20]([CH3:23])(=[O:21])=[O:22])=[CH:4][C:5]2[O:9][C:8]([C:10]([OH:12])=[O:11])=[C:7]([C:14](=[O:17])[NH:15][CH3:16])[C:6]=2[CH:18]=1参加物
4
反応物 2
生成物 1
試薬・触媒・溶媒 1
実験手順
To a suspension of methyl 5-bromo-3-(methylcarbamoyl)-6-(N-methylmethylsulfonamido)benzofuran-2-carboxylate (2.90 g, 6.92 mmol) in 1,4-dioxane/H2O (30 mL/5 mL) was added LiOH.H2O (870 mg, 20.75 mmol). The mixture was stirred at room temperature overnight. Then it was concentrated in vacuo, diluted with water, acidized with HCl (aq. 2 M) and extracted with EtOAc. The organic layer was washed with brine, dried over Na2SO4 and concentrated give the product of 5-bromo-3-(methylcarbamoyl)-6-(N-methylmethylsulfonamido)benzofuran-2-carboxylic acid (2.50 g, yield: 89%). It was used for the next step without further purification. 1H-NMR (DMSO-d6, 400 MHz) δ 9.16 (br s, 1H), 8.27 (s, 1H), 8.16 (s, 1H), 3.17 (s., 6H), 2.82 (d, J=4.4 Hz, 3H). (M+H)+: 405/407.