反应详情

To a solution of n-BuLi (2.0 M in hexanes, 11.1 mL, 22.2 mmol) in anhydrous THF (17 mL) at −78° C. was added drop wise 2,2,6,6-tetramethylpiperidine (3.26 g, 22.1 mmol). After being stirred for 15 minutes, a solution of the product from step A (5.86 g, 22.1 mmol) in THF (20 mL) was added. The reaction mixture was stirred at −78° C. for 2 hours, then dry ice (100 g) was added. The mixture was allowed to stand at room temperature overnight, then it was diluted with water and extracted with EtOAc. The combined organics were dried over MgSO4, filtered, then concentrated to afford the title compound. The material was used directly in the next step without further purification. 1H NMR (500 MHz, CDCl3): δ 7.70 (d, J=4.4 Hz, 1H); 0.44 (s, 9H).

1. stirringThe reaction mixture was stirred at −78° C. for 2 hours
2. waitto stand at room temperature overnight
3. extractionextracted with EtOAc
4. dry with materialThe combined organics were dried over MgSO4
5. filtrationfiltered
6. concentrationconcentrated