[CH3:1][O:2][C:3]1[C:8]([O:9][CH3:10])=[CH:7][N:6]=[C:5]([CH3:11])[CH:4]=1.C([Li])CCC.CN(C)[C:19](=[O:21])[CH3:20].[Cl-].[NH4+]>O1CCCC1.CCCCCC>[CH3:1][O:2][C:3]1[C:8]([O:9][CH3:10])=[CH:7][N:6]=[C:5]([CH2:11][C:19](=[O:21])[CH3:20])[CH:4]=1To a stirred solution of 4,5-dimethoxy-2-methylpyridine (2.92 g) in tetrahydrofuran (30 ml) was added a solution of n-butyllithium in n-hexane (1.63M, 14 ml) dropwise at −50° C. under a nitrogen atmosphere, and the mixture was warmed to 0° C. The mixture was cooled to −50° C., and N,N-dimethylacetamide (2.31 ml) was added dropwise. Then the mixture was warmed to room temperature, poured into a saturated aqueous ammonium chloride solution and extracted with ethyl acetate (100 ml×4). The combined organic layer was washed with brine, dried over sodium sulfate and evaporated under reduced pressure. The residue was purified by column chromatography (silica gel 100 g, n-hexane:ethyl acetate=1:1) to give 1-(4,5-dimethoxypyridin-2-yl)propan-2-one (1.59 g).
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