F[C:2]1[CH:7]=[N:6][CH:5]=[CH:4][N:3]=1.[CH:8]1([C:11]#[N:12])[CH2:10][CH2:9]1.C[Si]([N-][Si](C)(C)C)(C)C.[K+]>C1(C)C=CC=CC=1.O.CCOC(C)=O>[N:3]1[CH:4]=[CH:5][N:6]=[CH:7][C:2]=1[C:8]1([C:11]#[N:12])[CH2:10][CH2:9]1In a dry flask under argon, 2-fluoropyrazine (1.95 g, 19.9 mmol) and cyclopropanecarbonitrile (1.5 mL, 20. mmol) were dissolved in dry toluene (25 mL). The solution was cooled to 0° C. and potassium bis(trimethylsilyl)amide (1.0 M in THF, 20 mL, 20 mmol) was added slowly over 5 min via syringe. The black, opaque reaction mixture was allowed to warm to room temperature and stir for 4 h. The reaction was diluted with H2O (200 mL) and EtOAc (200 mL) and the layers were separated. The aqueous layer was back extracted with EtOAc (2×100 mL). The combined organic layers were dried over Na2SO4, filtered and concentrated to give a black oil. The oil was purified by flash chromatography (silica, 20→60% EtOAc/hexanes) to give 849 mg of the title compound as a light yellow oil, m/z 146.17 [M+1]+.
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