To a mixture of the tert-butyl {1-[4-(6-chloro-7,8-dimethyl-3-phenylimidazo[1,2-b]pyridazin-2-yl)phenyl]cyclobutyl}carbamate that was prepared in a manner analgous to that described for Intermediate Example Int-32 (179 mg, 0.360 mmol, 1.0 eq) in DCM (2.29 mL) and MeOH (1.44 mL) was added a solution of 4 M hydrogen chloride in dioxane (1.78 mL, 7.12 mmol, 20.0 eq) and the mixture was stirred overnight at rt. The mixture was poured onto ice, made alkaline with aqueous sodium hydroxide (2 N) and extracted with DCM. The combined organic phases were washed with brine, dried and concentrated in vacuo. The crude mixture was purified via MPLC (Biotage Isolera; 10 g SNAP cartridge: DCM→DCM/ethanol 95/5) to give 64 mg (44% yield) of the title compound.
