Sodium Carbonate → 1-[(4-Butylphenyl)methyl]piperazine

A 26.4 g. portion of 1-benzylpiperazine, 25 g. of potassium carbonate and 200 ml. of dry tetrahydrofuran were stirred and cooled. A 31.5 g. portion of 4-n-butyl benzoyl chloride and 100 ml. of tetrahydrofuran were added and the mixture stirred 18 hours. A 100 ml. portion of 1 N sodium hydroxide was added and the mixture stirred for one hour. The phases were separated. The aqueous phase was extracted with 100 ml. of chloroform. The extract was combined with the tetrahydrofuran layer, dried and evaporated to an oil. This oil was suspended in a mixture of 100 ml. of glacial acetic acid and 10 ml. of water, 4 g. of 10% palladium on carbon catalyst were added and the mixture reduced. The reaction mixture was filtered. The filtrate was washed with ethanol, evaporated to a syrup and triturated with ether, giving 17.5 g. of colorless crystals. A 17.0 g. portion of these crystals were dissolved in water and 10 N sodium hydroxide added to a pH>10. This mixture was extracted with two 200 ml. portions of chloroform. The extracts were combined, dried and evaporated to give 12.3 g. of 1-(p-n-butylbenzoyl)-piperazine as a viscous syrup. This was dissolved in 250 ml. of dry tetrahydrofuran, 2 g. of lithium aluminum hydride was added, and the mixture was stirred and refluxed for 20 hours. The reaction mixture was cooled, treated with aqueous sodium carbonate solution, and the tetrahydrofuran was removed in vacuo. The aqueous solution was extracted with chloroform followed by concentration of the extract in vacuo giving the title compound as a colorless oil, b.p. 127°-130° C./0.05 mm.

1. temperaturecooled
2. stirringthe mixture stirred for one hour
3. customThe phases were separated
4. extractionThe aqueous phase was extracted with 100 ml
5. customdried
6. customevaporated to an oil
7. additionThis oil was suspended in a mixture of 100 ml
8. additionof 10% palladium on carbon catalyst were added
9. filtrationThe reaction mixture was filtered
10. washThe filtrate was washed with ethanol
11. customevaporated to a syrup
12. customtriturated with ether
13. customgiving 17.5 g
14. extractionThis mixture was extracted with two 200 ml
15. customdried
16. customevaporated
17. customto give 12.3 g
18. dissolutionThis was dissolved in 250 ml
19. stirringthe mixture was stirred
20. temperaturerefluxed for 20 hours
21. temperatureThe reaction mixture was cooled
22. customthe tetrahydrofuran was removed in vacuo
23. extractionThe aqueous solution was extracted with chloroform
24. extractionextract in vacuo

ORD record

ord-6c250a3bb4ce441da441d8cc7408a1e9

Source dataset

uspto-grants-1983_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04421753