Cyclopropanecarbonitrile → 1-(Pyrazin-2-yl)cyclopropane-1-carbonitrile

Temperature

0 °C

In 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]+.

1. customThe black, opaque reaction mixture
2. temperatureto warm to room temperature
3. customthe layers were separated
4. extractionThe aqueous layer was back extracted with EtOAc (2×100 mL)
5. dry with materialThe combined organic layers were dried over Na2SO4
6. filtrationfiltered
7. concentrationconcentrated
8. customto give a black oil
9. customThe oil was purified by flash chromatography (silica, 20→60% EtOAc/hexanes)

ORD record

ord-d9dc536d0601435f818037faf18dbe19

Source dataset

uspto-grants-2013_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08552205B2