Synthesis
Lithium bis(trimethylsilyl)amide (1M tetrahydrofuran solution, 60.5 mL, 60.5 mmol) was slowly added dropwise to a solution of 2-cyanopyridine (3.0 g, 28.8 mmol) in anhydrous ether (30 mL) at 0 °C. The reaction mixture was kept cooled at 0 °C, followed by the addition of 3M hydrochloric acid (54 mL) with continuous stirring for 30 min. After completion of the reaction, water (135 mL) was added for dilution and the organic phase was separated. The aqueous phase was adjusted to pH 14 with saturated aqueous sodium hydroxide and subsequently extracted with dichloromethane (3 times). The organic extracts were combined, dried over anhydrous sodium sulfate and concentrated in vacuum to afford pyridine-2-carboxamidine (1.70 g, 49% yield).
