[O-][N+:2]1[CH:7]=[CH:6][CH:5]=[CH:4][C:3]=1/[CH:8]=[CH:9]/[C:10]([O:12][C:13]([CH3:16])([CH3:15])[CH3:14])=[O:11].C[Si]([C:21]#[N:22])(C)C.CN(C)C(Cl)=O.C(OCC)(=O)C>[N+](CC)([O-])=O.O>[C:21]([C:7]1[N:2]=[C:3](/[CH:8]=[CH:9]/[C:10]([O:12][C:13]([CH3:16])([CH3:15])[CH3:14])=[O:11])[CH:4]=[CH:5][CH:6]=1)#[N:22]
tert-Butyl (E)-3-(1-oxido-2-pyridyl)-2-propenoate (2.10 g, 9.5 mmol) was dissolved in nitroethane (10 ml), and trimethylsilyl cyanide (1.88 g, 19.0 mmol) and N,N-dimethylcarbamoyl chloride (2.04 g, 19.0 mmol) were added thereto. The reaction mixture was stirred at room temperature for 18 hrs and combined with ethyl acetate and water. The organic layer was washed with saturated aqueous sodium hydrogen carbonate solution and dried over anhydrous magnesium sulfate. The solvent was evaporated. The residue was subjected to a silica gel column chromatography. The fractions eluted with hexane-ethyl acetate (5:1, v/v) were collected and concentrated to give the titled compound (2.18 g, ca. 100%).
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