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.C(OCC)(=O)C>[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]1
A mixture of 2-fluoropyrazine (2.0 g, 20.4 mmol, 1 eq) and cyclopropanecarbonitrile (1.5 ml, 20.4 mmol, 1 eq) In a dry flask under an argon atmosphere were dissolved in dry toluene (50 ml). The solution was cooled to 0° C. and potassium bis(trimethylsilyl)amide (0.5 M in toluene, 40.9 ml, 20.45 mmol, 1 eq) was added slowly over 5 min via syringe. The black, opaque reaction mixture was allowed to warm to room temperature and stirred for 4 h. The reaction was diluted with water (200 ml) and ethyl acetate (200 ml), and the layers were separated. The aqueous layer was back extracted with ethyl acetate (2×100 ml). The combined organic layers were dried over Na2SO4, filtered and concentrated to give a black oil. The crude was purified by silica gel (60-120) column chromatography using 20% ethyl acetate in hexane as eluent to give 0.25 g of the product as light a yellow oil. Yield: 0.25 g (8.4%). 1H NMR (400 MHz, CD3OD): δ 1.84-1.86 (m, 4H), 8.51-8.55 (q, 2H), 8.89 (s, 1H). LCMS: (ES+) m/z=146.2 (M)+
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