反应详情

to a stirred solution of S-4-(tert-butyl-dimethylsilyloxy)benzyl 4-tert-butoxycarbonylpiperazine-1-thiocarboxylate (10 g, 22 mmol) in THF (100 mL) was added a solution of TBAF in THF (1 N, 24 mL, 24 mmol). The mixture was stirred at room temperature for 40 min then diluted with water (200 mL) and extracted with EtOAc (2×250 mL). The combined organic extracts were washed successively with water (250 mL) and brine (500 mL) then dried (MgSO4), filtered and concentrated to reveal a brown oil. Trituration with EtOAc/hexane afforded the product as a white solid (3.7 g, 47%): 1H-NMR (400 MHz, d6-DMSO) 9.32 (1H, m), 7.11 dt (2H, t, J 8.5, 2.5 Hz), 6.67 (2H, t, J 8.5, 2.5 Hz), 4.02 (2H, s), 3.43 (4H, m), 3.33 (4H, m) and 1.40 (9H, s).

1. extractionextracted with EtOAc (2×250 mL)
2. washThe combined organic extracts were washed successively with water (250 mL) and brine (500 mL)
3. dry with materialthen dried (MgSO4)
4. filtrationfiltered
5. concentrationconcentrated