[CH2:1]([O:8][C:9]1[CH:10]=[N:11][C:12]2[C:17]([C:18]=1[C:19](N)=[O:20])=[N:16][C:15]([O:22][CH3:23])=[CH:14][CH:13]=2)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[BH4-].[Na+].C(OCC)(=O)C>O1CCCC1.CO.[H-].[CH-]1C=CC=C1.[CH-]1C=CC=C1.[Cl-].[Zr+4]>[CH2:1]([O:8][C:9]1[CH:10]=[N:11][C:12]2[C:17]([C:18]=1[CH2:19][OH:20])=[N:16][C:15]([O:22][CH3:23])=[CH:14][CH:13]=2)[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1
A solution of 3-benzyloxy-6-methoxy-[1,5]naphthyridine-4-carboxylic acid amide (640 mg, 2.07 mmol, 1.0 eq) in tetrahydrofuran (50 mL) is added at room temperature to a flask charged with Schwartz's reagent (800 mg, 3.1 mmol, 1.5 eq) and the resulting mixture is stirred at room temperature for 10 minutes. Solvent is removed to give a crude that is purified by column chromatography (silica gel, eluent: petroleum ether:ethyl acetate, 1:1, v/v) to afford a mixture of aldehyde and alcohol. This mixture is dissolved in methanol (20 mL) and sodium borohydride (39 mg, 1.03 mmol, 0.5 eq) is added at room temperature. After 5 minutes stirring at room temperature, solvent is removed to give a crude that is purified by column chromatography (silica gel, eluent: petroleum ether:ethyl acetate, 4:1, v/v) to afford (3-benzyloxy-6-methoxy-[1,5]naphthyridine-4-yl)-methanol as a white solid (390 mg, 64% yield).
読み込み中…
