反应详情

Analogously to general procedure (I) N-(3,3-dimethyl-6-nitro-2-oxo-2,3-dihydro-1H-indol-5-yl)-acetamide (1 g) is alkylated using butyl iodide (1.8 ml; 15.4 mmol) and K2CO3 (2.1 g; 15.2 mmol) at RT for 20 h. After aqueous work-up and flash chromatography on silica gel eluting with CH2Cl2/MeOH (30:1) the alkylated acetamide (0.94 g; 2.93 mmol) is de-acetylated under reflux conditions in 2-propanol (3 ml) and hydrochloric acid (6 N; 11 ml). Pure 5-amino-1-butyl-3,3-dimethyl-6-nitro-1,3-dihydro-indol-2-one (0.64 g) is obtained by flash chromatography on silica gel eluted with CH2Cl2/MeOH (50:1).

1. customat RT
2. customfor 20 h