To a mixture of the tert-butyl {1-[4-(6-ethoxy-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-36 (210 mg, 0.410 mmol, 1.0 eq) in DCM (2.64 mL) and MeOH (1.66 mL) was added a solution of 4 M hydrogen chloride in dioxane (2.05 mL, 8.19 mmol, 20.0 eq) and the mixture was stirred overnight at rt. The mixture was poured onto ice, made alkaline, treated with DCM and filtered through a phase separator. The volatile components of the organic phase were removed in vacuo to give 145 mg (82% yield) of the title compound.
