反应详情

温度

80 °C

Ethyl 7-chloro-6-(2-ethoxy-2-oxoethyl)-5-methylpyrazolo[1,5-a]pyrimidine-2-carboxylate (5 g, 15.35 mmol) and sodium iodide (9.20 g, 61.4 mmol) were suspended in acetonitrile (80 mL) and the resulting mixture was heated at 80° C. for 2 h. At this point LCMS indicated completion of reaction and appearance of the desired product. After cooling to rt, the reaction mixture was diluted with ethyl acetate and washed with water and aqueous Na2S2O3, dried (Na2SO4), filtered and concentrated. Then crude product was triturated with ethyl acetate/hexane to afford ethyl 6-(2-ethoxy-2-oxoethyl)-7-iodo-5-methylpyrazolo[1,5-a]pyrimidine-2-carboxylate (5.7 g, 13.66 mmol, 89% yield) as off white solid. 1H NMR (500 MHz, CDCl3) δ: 7.32 (s, 1H), 4.51 (d, J=7.0 Hz, 2H), 4.25 (d, J=7.0 Hz, 2H), 4.02 (s, 2H), 2.68 (s, 3H), 1.48 (t, J=7.2 Hz, 3H), 1.31 (t, J=7.2 Hz, 3H). LCMS (M+H)=418.2.