Potassium Carbonate → (4S,6S)-4-(5-(6-ethynylpyridin-3-yl)-2-fluorophenyl)-4-(fluoromethyl)-6-(trifluoromethyl)-5,6-dihydro-4H-1,3-oxazin-2-amine

A mixture of (4S,6S)-4-(2-fluoro-5-(6-((trimethylsilyl)ethynyl)pyridin-3-yl)phenyl)-4-(fluoromethyl)-6-(trifluoromethyl)-5,6-dihydro-4H-1,3-oxazin-2-amine (0.2034 g, 0.435 mmol, Example 111), potassium carbonate (0.301 g, 2.175 mmol), and MeOH (3 mL) was stirred at room temperature for 1.25 h. The reaction mixture was concentrated in vacuo, diluted with water and extracted with DCM three times. The combined organic layers were washed with brine, dried over sodium sulfate, filtered and concentrated. The crude material was purified by silica gel chromatography: 0-100% EtOAc/hexane in 12 min. The product was obtained as a white solid (0.16 g, 93% yield). MS m/z=396 [M+H]+. Calculated for C19H14F5N3O: 395.3.