2,4(1H,3H)-Pyrimidinedione, 1-ethyl-5-(trifluoromethyl)- synthesis

Yield:1097629-10-1 27%

Reaction Conditions:

with potassium carbonate in N,N-dimethyl-formamide at 20;

Steps:

To a stirred mixture of 5-trifluoromethyl uracil (1.8 g, 10 mmol) and powdered anhydrous potassium carbonate (1.38 g, 10 mmol) in DMF (50 mL), was added iodoethane (0.8 mL, 10 mmol). After stirring overnight at room temperature, the mixture was evaporated in vacuo and the residue was purified by silica gel column chromatography (eluent ethyl acetate rhexane (1:1)) to afford 563 mg (27%) of l-ethyl-5-trifluoromethyl uracil as a white solid, m.p. 259-260⁰C; ¹H-NMR (200 MHz, CDCh/CDsOD) δ 1.35 (3H, d, J=7.2 Hz), 3.87 (2H, q, J=7.2 Hz), 7.94 (IH, s); m/z (EI) 208 (M⁺).

References:

WO2009/5674,2009,A2 Location in patent:Page/Page column 390; 391