反应详情

To a solution of 4-biphenyl-2-ylmethyl-piperazine-1-carboxylic acid tert-butyl ester (9.89 g, 28.1 mmol) in dichloromethane (112.5 ml) at rt was added TFA (37.5 ml). The reaction was stirred for 4.5 h and then concentrated under reduced pressure. To the crude product was added H2O (20 ml) followed by 1M NaOH and then 5M NaOH to adjust the pH to ˜8-9. The mixture was extracted with dichloromethane (×2) and the combined organic extracts were washed with H2O, brine, dried (Na2SO4), filtered and concentrated under reduced pressure to provide 1-biphenyl-2-ylmethyl-piperazine (6.55 g, 92%) which was used without further purification. HPLC-MS 253 [M+1]+.

1. concentrationconcentrated under reduced pressure
2. additionTo the crude product was added H2O (20 ml)
3. extractionThe mixture was extracted with dichloromethane (×2)
4. washthe combined organic extracts were washed with H2O, brine
5. dry with materialdried (Na2SO4)
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure