Cl.[NH2:2][CH2:3][C:4](=[O:9])[C:5]([CH3:8])([CH3:7])[CH3:6].C(N(CC)C(C)C)(C)C.Cl[C:20](=[O:26])[C:21]([O:23][CH2:24][CH3:25])=[O:22]>C(Cl)Cl>[CH2:24]([O:23][C:21](=[O:22])[C:20]([NH:2][CH2:3][C:4](=[O:9])[C:5]([CH3:8])([CH3:7])[CH3:6])=[O:26])[CH3:25]To a mixture of 1-amino-3,3-dimethylbutan-2-one hydrochloride salt (35 g, 231 mmol) in CH2Cl2 (500 mL) at 0° C. are added N,N-diisopropylethylamine (74 g, 577 mmol) and ethyl chloro(oxo)acetate (31.5 g, 231 mmol) slowly over a period of 15 min. The reaction mixture is stirred at room temperature for 2 h and is filtered through Celite. The filtrate is concentrated to afford the title compound (40 g, 81%).
Wird geladen…