Example 15: Synthesis of 4-chloro-6-(trifluoromethyl)pyrimidin-2-amine (24)
2-Amino-6-(trifluoromethyl)pyrimidin-4-ol (200 mg, 1.1 mmol) was dissolved in a mixed solution of phosphorus oxychloride (POCl3, 3 eq., 0.3 mL, 3.3 mmol) and N,N-dimethylaniline (0.28 mL, 2 eq.). The reaction mixture was heated with stirring at 70 °C for 4 hours. Upon completion of the reaction, the mixture was slowly poured into an ice-water mixture to quench the reaction and the precipitated solid was collected by filtration to afford the target compound 24 in 59% yield. The product was identified by electrospray ionization mass spectrometry (ESI-MS), m/z 198 [M + H]+.
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[4] Patent: US2010/167935, 2010, A1. Location in patent: Page/Page column 24
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