反应详情

To a solution of 2-nitro-5-(thiophen-2-yl)aniline (0.30 g, 1.36 mmol, 1 eq.) and triphosgene (0.24 g, 0.82 mmol, 0.6 eq.) in dichloromethane (7 mL) at 0° C. was added TEA (0.38 mL, 2.90 mmol, 2 eq.). The reaction was stirred at room temperature for 2 h, then cooled down to 0° C. Tert-butyl 3-(hydroxymethyl)azetidine-1-carboxylate (0.31 g, 1.64 mmol, 1.2 eq.) in dichloromethane (7 mL) and TEA (0.38 mL, 2.90 mmol, 2 eq.) were added at 0° C. The reaction was warmed to room temperature and stirred for 1 h. The reaction was diluted with dichloromethane and washed with citric acid solution then brine. The organic layer was separated, dried over sodium sulfate and concentrated. The crude product was purified by column chromatography (silica gel, 25% EtOAc/hexanes) to obtain tert-butyl 3-((((2-nitro-5-(thiophen-2-yl)phenyl)carbamoyl)oxy)methyl)azetidine-1-carboxylate (0.59 g, 85% yield).

1. temperaturecooled down to 0° C
2. temperatureThe reaction was warmed to room temperature
3. stirringstirred for 1 h
4. washwashed with citric acid solution
5. customThe organic layer was separated
6. dry with materialdried over sodium sulfate
7. concentrationconcentrated
8. customThe crude product was purified by column chromatography (silica gel, 25% EtOAc/hexanes)