反应详情

A mixture of tert-butyl 5-(bromomethyl)pyrazin-2-ylcarbamate (0.75 g, 2.60 mmol) and NaCN (0.255 g, 5.21 mmol) in DMF (5 mL) was stirred at room temperature for 50 min. The reaction mixture was cooled down to room temperature, diluted with 0.5 N NaOH (10 mL) and extracted with EtOAc (2×20 mL), and EtOAc layers were combined, washed with 0.5 N NaOH (10 mL), dried (Na2SO4), concentrated and the crude residue was purified by flash chromatography on silica gel eluted with gradient EtOAc/CH2Cl2 (0-20%) to afford tert-butyl 5-(cyanomethyl)pyrazin-2-ylcarbamate (0.40 g, 65.6% yield). LCMS (MH+-tBu): 179.0 (MH+), 0.68 min; 1H NMR (400 MHz, CDCl3) δ ppm 9.28 (s, 1H), 8.32 (s, 1H), 7.59 (br. s., 1H), 3.91 (s, 2H), 1.57 (s, 9H).

1. temperatureThe reaction mixture was cooled down to room temperature
2. extractionextracted with EtOAc (2×20 mL), and EtOAc layers
3. washwashed with 0.5 N NaOH (10 mL)
4. dry with materialdried (Na2SO4)
5. concentrationconcentrated
6. customthe crude residue was purified by flash chromatography on silica gel
7. washeluted with gradient EtOAc/CH2Cl2 (0-20%)