反应详情

温度

0 °C

The product of the Example 45b (17.1 g, 50 mmol) was dissolved in CH2Cl2 (400 mL). The solution was cooled to 0° C. and TFA (80 mL) was added drop-wise. The ice bath was removed and the reaction mixture was stirred at room temperature overnight, then the solvent. was evaporated. The residue was treated with aqueous sodium carbonate (10%) and extracted with EtOAc. The combined organic extracts were washed with water, brine, dried over sodium sulfate, and the solvent was evaporated. Trituration of the resulting solid with hexane gave the pure product as a white solid. Mp 64-68° C. 1HNMR (300 MHz, CDCl3) δ 7.67 (d, J=8.5 Hz, 2H), 7.66 (d, J=1.3, 1H), 7.4 (dd, J=8.5 and 1.8 Hz, 1H), 7.18-7.08 (m, 2H), 4.18 (t, J=5.4 Hz, 2H), 3.89 (s, 3H), 3.80 (q, J=7.1 Hz, 1H), 2.73 (t, J=5.4 Hz, 2H), 2.31 (s, 3H), 1.56 (d, J=7.1 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 174.5, 157.6, 135.6, 133.6, 129.2, 128.8, 127.1, 126.1, 125.8, 118.9, 105.5, 63.9, 55.2, 50.0, 45.3, 36.0, 18.4.

1. customThe ice bath was removed
2. customwas evaporated
3. additionThe residue was treated with aqueous sodium carbonate (10%)
4. extractionextracted with EtOAc
5. washThe combined organic extracts were washed with water, brine
6. dry with materialdried over sodium sulfate
7. customthe solvent was evaporated