A stirred solution of 6-bromo-4-(((3S,4S)-1-(5-cyanopyridin-2-yl)-4-methylpyrrolidin-3-yl)amino)pyrrolo[1,2-b]pyridazine-3-carboxamide (55 mg, 0.125 mmol, from Step 1 of Example 158), ethyl 2-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazol-1-yl)acetate (70.0 mg, 0.250 mmol), potassium phosphate tribasic (80 mg, 0.375 mmol), palladium(II) acetate (5.61 mg, 0.025 mmol) and 1,1′-bis(di-tert-butylphosphino)ferrocene (12.00 mg, 0.025 mmol) in N,N-dimethylformamide (1 mL) was degassed by vacuum-N2 refill cycle twice. The sealed tube was then heated at 100° C. for 40 min. The reaction mixture was diluted with water and filtered. The filter cake was washed with water and dried under vacuum to give crude ethyl 2-(4-(3-carbamoyl-4-(((3S,4S)-1-(5-cyanopyridin-2-yl)-4-methylpyrrolidin-3-yl)amino)pyrrolo[1,2-b]pyridazin-6-yl)-1H-pyrazol-1-yl)acetate (76.8 mg), which was used in the next step without purification.
