Synthesis
Urea (2.9 g, 0.05 mol), ethyl 4,4,4-trifluoro-3-oxobutanoate (8.9 g, 0.05 mol) and triethyl orthoformate (7.9 g, 0.05 mol) were dissolved in ethanol (10 mL) under nitrogen protection. The reaction mixture was heated to 80 °C and maintained at this temperature for 4 hours. Upon completion of the reaction, the mixture was cooled to 20 °C and sodium ethanolate solution (21 wt% ethanol solution, 16.9 g, 0.05 mol) was slowly added with stirring for 15 minutes. After addition, stirring of the reaction mixture was continued for 2 hours. Subsequently, water (75 mL) and acetic acid (2 mL) were added to the reaction system at 20 to 30 °C. The resulting slurry was filtered and the filter cake was washed with water (20 mL) and dried at 45 °C. A final product of 8.2 g (72% yield) of the target product ethyl 2-hydroxy-4-trifluoromethyl-5-pyrimidinecarboxylate was obtained as a white solid.1H NMR (400 MHz, (CD3)2SO): δ = 8.69 (s, 1H), 4.24 (q, J = 7.1 Hz, 2H), 1.28 (t, J = 7.1 Hz, 3H). 13C NMR (100 MHz, (CD3)2SO): δ = 161.4, 158.7 (q, J = 35 Hz), 155.5, 154.7, 119.2 (q, J = 278 Hz), 105.7, 61.3, 13.7.
