A solution of lithium diisopropylamine (1.8 M, 4.96 mL, 8.92 mmol) in THF (8 mL) was placed under an Argon atmosphere and was cooled to −78° C. A solution of N-[3-methyl-5-(1,3-thiazol-5-yl)phenyl]-4-(trifluoromethyl)pyrimidin-2-amine (Intermediate 4, 1200 mg, 3.57 mmol) in THF (8 mL) was cooled to −78° C. and added drop wise to the LDA solution. The reaction mixture was stirred 30 minutes at −78° C. The product of Step 1 (625 mg, 3.57 mmol) in THF (8 mL) was added drop wise and the reaction was allowed to warm to room temperature overnight. The mixture was quenched with brine, diluted with ethyl acetate. The organics were washed with saturated NaHCO3, followed by brine, dried (Na2SO4), filtered and concentrated. The residue was purified by column chromatography on silica (20-100% ethyl acetate in hexanes) to afford 2-methyl-N-{3-[5-(3-methyl-5-[[4-(trifluoromethyl)pyrimidin-2-yl]amino}phenyl)-1,3-thiazol-2-yl]oxetan-3-yl]propane-2-sulfinamide (1.10 g, 2.140 mmol, 60.0% yield). MS ESI: [M+H]+ m/z 512.1.
