反应详情

From 11.52 g. of 4-ethoxycinnamic acid and 10.71 g. of thionylchloride was prepared 4-ethoxycinnamoyl chloride, a solution of which in tetrahydrofuran was added gradually to a solution of 23.4 g. of piperazine hexahydrate, 20.67 g. of 47% hydrobromic acid and 90 ml. of ethanol. The resulting mixture was stirred overnight at room temperature and cooled with ice, the forming crystals being filtered off. The filtrate was condensed and treated just as in Reference example 1 to obtain 11.23 g. of the desired product (72% yield). The product was treated with concentrated hydrochloric acid to give the corresponding hydrochloride.

1. temperaturecooled with ice
2. filtrationthe forming crystals being filtered off
3. customcondensed
4. additiontreated just as in Reference example 1
5. customto obtain 11.23 g