反应 #470439
ord-d3a42bce36734cdfa320fdae2d93aa99
反应方程式
反应条件
后处理
- 1其他the heating bath was removed
- 2温度maintained a constant temperature
- 3温度After cooling
- 4过滤the mixture was filtered
- 5其他evaporated to a residue which
- 6过滤The brown precipitate was filtered off
- 7洗涤washed with cold water
- 8其他freeze-dried
实验过程
Sodium (356 mg, 15.5 mmol) was carefully added to ethanol (5.9 mL) to prepare sodium ethoxide solution in ethanol. The above freshly prepared ethanol solution (3.5 mL) was added to a stirred suspension of propionimidamide hydrochloride (1.05 g, 9.69 mmol). The mixture was warmed to 55° C., then the heating bath was removed and a solution of mucobromic acid (1 g, 3.87 mmol) in ethanol was added dropwise at a rate which maintained a constant temperature, followed by a further sodium ethoxide solution (2 mL). After cooling, the mixture was filtered and evaporated to a residue which was shaken vigorously with hydrochloric acid (2 M×2.4 mL). The brown precipitate was filtered off and washed with cold water, then freeze-dried to give 5-Bromo-2-ethylpyrimidine-4-carboxylic acid (330 mg, 37%) as a yellow solid. LCMS: 231 [M+1]+, 1H NMR (400 MHz, DMSO-d6): δ 1.25 (t, J=7.6 Hz, 3H), 2.88 (q, J=7.6 Hz, 2H), 9.05 (s, 1H).