反应详情

4N Hydrogen chloride/ethyl acetate solution (10.0 ml, 40.0 mmol) was added to a solution of 4-(2-fluoro-4-nitrophenyl)piperazine-1-carboxylic acid tert-butyl ester (compound of Reference Example 14; 2.50 g, 7.68 mmol) in ethyl acetate (10 ml) under ice cooling, and the mixture was stirred at room temperature for 12 hours. The reaction mixture was adjusted to pH=9 by addition of saturated aqueous sodium hydrogencarbonate, and concentrated under reduced pressure. The obtained solid was collected by filtration and washed with water to give the title compound (0.563 g, 37%) as a yellow solid.

1. concentrationconcentrated under reduced pressure
2. filtrationThe obtained solid was collected by filtration
3. washwashed with water