To a solution of N-[(4aR,7aS)-7a-phenyl-4a,5,6,7-tetrahydro-4H-pyrrolo[3,4-d][1,3]thiazin-2-yl]benzamide hydrochloride (95 mg, 0.25 mmol) and 2-(2-chloro-5-fluoro-pyrimidin-4-yl)propan-2-ol (195 mg, 0.57 mmol) in 1,4-dioxane (5.0 mL) is added diisopropylethylamine (150 μL, 0.86 mmol). The resulting solution is heated at 100° C. for 23 hours, cooled to room temperature, and concentrated. The residue is dissolved in methanol (5.0 mL), followed by the addition of lithium hydroxide (100 mg, 4.11 mmol). The resulting solution is heated at 55° C. for 16 hrs and then cooled to room temperature and concentrated. The residue is purified with a 5 g SCX column, eluting first with MeOH/DCM (¼, 50 mL), followed by elution with ammonia in MeOH (7.0 N)/DCM (¼, 50 mL). The basic filtrate is concentrated, and further purified by silica gel flash chromatography, eluting with a gradient of ammonia in MeOH (2.0 M) in dichloromethane (0% to 10%) to give the free base form of the title compound as a colorless oil. El/MS (m/e): 402.00 (M+H). 19F-NMR (CDCl3): δ (ppm) −154.62. 1H-NMR (CDCl3): δ (ppm) 7.38 (m, 5H), 4.11 (d, 1H), 4.01 (d, 1H), 3.83 (m, 2H), 3.05 (dd, 1H), 2.92 (dd, 1H), 2.81 (m, 1H), 2.37 (s, 3H), 1.53 (s, 6H). The purified material is dissolved in dichloromethane (2 mL), followed by the addition of HCl (1.0 M in diethyl ether, 60 μL, 0.06 mmol) and then concentrated to give the title compound as a white solid (22 mg, 20%).
