反应详情

N-(2-Aminoethyl)piperazine (24.4 g) and benzaldehyde (26.9 ml) were dissolved in toluene (250 ml), and a Dean-Stark device was attached thereto, and the mixture was heated under reflux for 3 hours. After cooled to room temperature, a part (10 ml) of the reaction mixture was removed and concentrated to give N-[2-(benzylidene)aminoethyl]piperazine (1.4 g). Di (t-butyl) dicarbonate (45 g) was added to the remainder (about 240 ml) of the reaction mixture, and the mixture was stirred overnight at room temperature. 1 N aqueous potassium hydrogen sulfate (220 ml) was added thereto, and the mixture was vigorously stirred for 5 hours at room temperature, and the aqueous layer was partitioned by adding diethyl ether. The aqueous layer was basified by adding sodium hydroxide (solid), and the organic layer was partitioned by adding chloroform, washed with water, dried, and evaporated to give the title compound (14.9 g).

1. temperaturethe mixture was heated
2. temperatureunder reflux for 3 hours
3. customa part (10 ml) of the reaction mixture was removed
4. concentrationconcentrated