II-1-1: Synthesis of 2-cyano-3-methylpyridine
10.9 g (0.1 mol) of 3-methylpyridine-N-oxide was mixed with 12.6 g (0.1 mol) of dimethyl sulfate and the reaction was stirred at 70-75°C for 2 hours. Subsequently, a solution prepared from 13.0 g (0.2 mol) potassium cyanide dissolved in 10-40 mL of water was slowly added dropwise to the reaction system while maintaining stirring. After the dropwise addition was completed, the reaction mixture was continued to be stirred at the same temperature for 1 hour and then at room temperature for another 1 hour. Upon completion of the reaction, it was diluted with 150 mL of water and extracted with dichloromethane. The organic phases were combined, dried with anhydrous sodium sulfate and concentrated under reduced pressure. The resulting crude product was purified by silica gel column chromatography (eluent ratio: ethyl acetate/hexane = 2:8 to 3:7, 2:8 for the second time), and finally recrystallized from hexane to give 2.20 g of colorless solid product in 18.6% yield. The melting point of the product was 82.5-83.5 °C. IR (KBr, cm-1): 2210, 1560.
