A mixture of crude tert-butyl (1-{4-[bromo(phenyl)acetyl]phenyl}cyclobutyl)carbamate [that was prepared in a manner analgous to that described for Intermediate Example Int-1-A] (300 mg, ˜80% purity, 0.540 mmol, 1.0 eq), 6-ethoxy-4,5-dimethylpyridazin-3-amine (that was prepared in a manner analgous to that described for Intermediate Example Int-36, Step 1, 124 mg, ˜80% purity, 0.590 mmol, 1.1 eq) and N,N-diisopropylethylamine (100 μL, 0.590 mmol, 1.1 eq) in butyronitrile (3.3 mL) was heated for 3.5 hours at 125° C. On cooling the reaction mixture was concentrated in vacuo. The crude mixture was purified via preparative MPLC (Biotage Isolera; 50 g SNAP-cartridge: hexane/EtOAc 9/1→hexane/EtOAc 1/1) to give 220 mg (70% yield) of the title compound.
