C[O:2][C:3]([C:5]1([C:11]2[C:16]([CH3:17])=[CH:15][C:14]([Br:18])=[CH:13][N:12]=2)[CH2:10][CH2:9][O:8][CH2:7][CH2:6]1)=[O:4].[OH-].[Na+]>O1CCCC1.CO>[Br:18][C:14]1[CH:15]=[C:16]([CH3:17])[C:11]([C:5]2([C:3]([OH:4])=[O:2])[CH2:10][CH2:9][O:8][CH2:7][CH2:6]2)=[N:12][CH:13]=1To a solution of 4-(5-bromo-3-methylpyridin-2-yl)tetrahydro-2H-pyran-4-carboxylic acid methyl ester (745 mg) in tetrahydrofuran (5 ml) and methanol (5 ml) was added 4 N aqueous solution of sodium hydroxide (5 ml) at room temperature, and stirred overnight. After completion of the reaction, the organic solvent was evaporated, diluted with 1 N aqueous solution of sodium hydroxide and water, diethyl ether was added thereto, and the aqueous layer was separated. The aqueous layer was ice-cooled, concentrated hydrochloric acid was added thereto to adjust the layer to pH 4, extracted with chloroform, the organic layer was dried over anhydrous sodium sulfate, and then the solvent was evaporated to give 4-(5-bromo-3-methylpyridin-2-yl)tetrahydro-2H-pyran-4-carboxylic acid (421 mg) as a white solid. MS (ESI) m/z: 300, 302 (M+H)+.
読み込み中…