To methyl 3-(1-chlorophthalazin-6-yl)-4-methylbenzoate (2.49 g, 7.96 mmol) and zinc cyanide (1.87 g, 15.9 mmol) was added DMF (39.8 mL). The mixture was sparged with nitrogen for 15 min, and tris(dibenzylideneacetone)dipalladium(0) chloroform adduct (0.330 g, 0.318 mmol) and 1,1′-bis(diphenylphosphino)ferrocene (0.177 g, 0.318 mmol) were added. The reaction was heated to 100° C. for 30 min. The reaction mixture was diluted with 100 mL ethyl acetate, partitioned with sodium bicarbonate (saturated, aqueous), and the organics were washed 3×50 mL with sodium bicarbonate (saturated, aqueous), separated, dried over sodium sulfate, concentrated in vacuo, and purified by flash chromatography to give the title compound. MS (ES+): 304(M+H)+.
