[C:1]([CH2:3][C:4]([O:6][CH2:7][CH3:8])=[O:5])#[N:2].[H-].[Na+].F[C:12]1[CH:21]=[CH:20][C:15]([C:16]([O:18][CH3:19])=[O:17])=[CH:14][C:13]=1[N+:22]([O-:24])=[O:23]>CN(C)C=O.Cl.C(OCC)(=O)C>[C:1]([CH:3]([C:12]1[CH:21]=[CH:20][C:15]([C:16]([O:18][CH3:19])=[O:17])=[CH:14][C:13]=1[N+:22]([O-:24])=[O:23])[C:4]([O:6][CH2:7][CH3:8])=[O:5])#[N:2]Ethyl 2-cyanoacetate (10.9 mL, 102 mmol) was slowly added to a 60% suspension of sodium hydride (4.10 g, 102 mmol) in N,N-dimethylformamide (125 mL) at 0° C. to give a gray suspension. The mixture was stirred at 0° C. for 15 minutes and methyl 4-fluoro-3-nitrobenzoate (10.2 g, 51 mmol) in N,N-dimethylformamide (125 mL) was added. The resulting deep red mixture was stirred at 0° C. for 30 minutes and at room temperature for 3 hours. The reaction mixture was diluted with 1N HCl (40 mL) and ethyl acetate (40 mL). The separated aqueous layer was extracted with ethyl acetate (3×50 mL). The organic layers were combined and dried over anhydrous sodium sulfate, filtered and concentrated to afford a residue (26 g) which was purified by flash-chromatography (started with 100% hexanes and gradually added ethyl acetate increments to complete with 100% ethyl acetate) to afford 14.9 g of the title compound. LCMS m/z 291.0 (M−H)−, retention time (on analytical HPLC)=1.76 minutes.
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