To a 100-mL round-bottom flask is added 6-piperazin-1-yl-nicotinonitrile (9.60 g, 50 mmol), 1,4-dichlorophthalazine (11.2 g, 55.1 mmol, 1.1 eq), Et3N (3.5 mL, 250 mmol, 5 eq.), and NMP (100 mL). The mixture is heated to 80° C. for 2.5 h. Upon cooling to room temperature, the reaction is poured into H2O (500 mL) and the precipitate isolated by filtration, rinsing with additional H2O. Crude material is purified by recrystallization (CH2Cl2:heptanes) to afford 8.96 g title compound as a beige solid.
