反应详情

温度

0 °C

At 0° C., to a solution of 4-isopropylbenzoic acid (3.28 g, 20.0 mmol), triethylamine (2.12 g, 2.93 mL, 21.0 mmol) in dichloromethane/THF (15 mL/5 mL), is added isobutylchloroformate (2.87 g, 2.72 mL, 21.0 mmol). The mixture is stirred at 0° C. for 20 min. with warming to room temperature over 2 hr., and then treated with ethyl hydrazinoacetate (2.18 g, 21.0 mmol) and stirred overnight. The mixture is then washed with water, brine and dried over Na2SO4. The crude product obtained after the removal of the solvent is chromatographed (silica gel, 5:1 dichloromethane-ethyl acetate) to provide ethyl[2-(4-isopropylbenzoyl)hydrazino]acetate (4.85 g, 97%). MS (ES+): m/e 251.

1. temperaturewith warming to room temperature over 2 hr
2. stirringstirred overnight
3. washThe mixture is then washed with water, brine
4. dry with materialdried over Na2SO4
5. customThe crude product obtained
6. customafter the removal of the solvent
7. customis chromatographed (silica gel, 5:1 dichloromethane-ethyl acetate)