C1(C)C=CC=CC=1.[H-].C([Al+]CC(C)C)C(C)C.C([O:20][C:21]([C:23]1[CH:28]=[CH:27][C:26]([O:29][CH:30]([F:32])[F:31])=[CH:25][N:24]=1)=O)C.[BH4-].[Na+].O.O.O.O.O.O.O.O.O.O.S([O-])([O-])(=O)=O.[Na+].[Na+]>CO.C1COCC1>[F:32][CH:30]([F:31])[O:29][C:26]1[CH:27]=[CH:28][C:23]([CH2:21][OH:20])=[N:24][CH:25]=1A toluene solution (13.8 mL, 13.8 mmols) of 1N diisobutylaluminium hydride was added to a THF solution (40 mL) of 2-ethoxycarbonyl-5-difluoromethoxypyridine (1.0 g, 4.6 mols) and stirred at 0° C. for 40 minutes. Successively sodium borohydride (174 mg, 4.6 mmols) and methanol (2 mL) were added and stirred at 0° C. for 30 minutes. Sodium sulfate decahydrate was added to the reaction liquid and stirred overnight at room temperature. Filtering the insoluble matter with Celite, the solvent was concentrated under reduced pressure. The residue was purified on silica gel column chromatography (C-300, hexane:ethyl acetate=3:2-2:3) to provide the title compound (738 mg, 87%).
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