反应详情

In 100 ml of chloroform was suspended 25 g (120 millimoles) of 2,4-dimethoxycinnamic acid. At room temperature, 44 ml (about 600 millimoles) of thionyl chloride was added dropwise. The mixture was stirred at room temperature for 1.5 hours, and the excess of thionyl chloride and chloroform were distilled off. The residue was diluted with 200 ml of chloroform, and added dropwise at room temperature to 300 ml of of a chloroform solution of 30.2 g (120 millimoles) of benzhydrylpiperazine and 24.3 g (240 millimoles) of triethylamine. The mixture was stirred at room temperature for 3 hours, and then a 10% aqueous solution of sodium bicarbonate was added. The mixture was shaken and the organic layer was separated, washed with water, and dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure. The resulting oily product was diluted with 200 ml of ethanol, and 15 ml of concentrated hydrochloric acid was added. The crystals precipitated were collected by filtration. Recrystallization from hydrous methanol gave 22.7 g (yield 39.5%) of 1-benzhydryl-4-(2,4-dimethoxycinnamoyl)piperazine hydrochloride as pale yellow crystals.

1. distillationthe excess of thionyl chloride and chloroform were distilled off
2. additionThe residue was diluted with 200 ml of chloroform
3. stirringThe mixture was stirred at room temperature for 3 hours
4. stirringThe mixture was shaken
5. customthe organic layer was separated
6. washwashed with water
7. dry with materialdried over anhydrous magnesium sulfate
8. distillationThe solvent was distilled off under reduced pressure
9. additionThe resulting oily product was diluted with 200 ml of ethanol, and 15 ml of concentrated hydrochloric acid
10. additionwas added
11. customThe crystals precipitated
12. filtrationwere collected by filtration
13. customRecrystallization from hydrous methanol