反应详情

To 3-(tert-butyldimethylsilyloxy)benzaldehyde (Example 12-1c) (3.00 g, 12.7 mmol) in DCE (100 mL) was added ethyl 2-amino-2-methylpropanoate hydrochloride (25 mmol, ˜2 equiv.), molecular sieves 4A (5 g), and Et3N (2 equiv.). The mixture was stirred for 6 hours at room temperature and treated with NaBH(OAc)3 (2 equiv.). After the addition was completed, the reaction mixture was stirred overnight under nitrogen. The mixture was diluted with DMC (200 mL), carefully quenched with saturated aqueous NaHCO3 solution and the layers were separated. The aqueous phase was further extracted with DCM (2×100 mL). The combined organic extract was washed with water (50 mL), brine (100 mL) and dried over Na2SO4. The solvent was removed under vacuum and the residue was purified over silica gel using hexanes/EtOAc (2/8) to give ethyl 2-(3-(tert-butyldimethylsilyloxy)benzylamino)-2-methylpropanoate (4.02 g, 90%). MS 352 (MH+)

1. additionAfter the addition
2. stirringthe reaction mixture was stirred overnight under nitrogen
3. additionThe mixture was diluted with DMC (200 mL)
4. customcarefully quenched with saturated aqueous NaHCO3 solution
5. customthe layers were separated
6. extractionThe aqueous phase was further extracted with DCM (2×100 mL)
7. extractionThe combined organic extract
8. washwas washed with water (50 mL), brine (100 mL)
9. dry with materialdried over Na2SO4
10. customThe solvent was removed under vacuum
11. customthe residue was purified over silica gel