反应详情

温度

0 °C

1-Benzylpiperazine (2.7 ml) and (2R)-1-BOC-piperazine-2-carboxylic acid (3.571 g) were suspended in DMF (150 ml) and stirred at 0° C. Triethylamine (4.33 ml) was added followed by PyBOP reagent (8.08 g). The mixture was allowed to warm to room temperature overnight, concentrated to approximately a third of the volume in vacuo and partitioned between brine (75 ml) and ethyl acetate (2×200 ml). Combined organic extracts were treated with saturated aqueous sodium bicarbonate (75 ml) and brine (75 ml), dried (sodium sulphate), concentrated in vacuo using high vacuum to remove DMF traces and purified by chromatography eluting with 0-15% methanol/dichloromethane. This gave tert-butyl (2R)-2-[(4-benzylpiperazin-1-yl)carbonyl]piperazine-1-carboxylate as a white glass (5.01 g).

1. temperatureto warm to room temperature overnight
2. concentrationconcentrated to approximately a third of the volume in vacuo
3. custompartitioned between brine (75 ml) and ethyl acetate (2×200 ml)
4. additionCombined organic extracts were treated with saturated aqueous sodium bicarbonate (75 ml) and brine (75 ml)
5. dry with materialdried (sodium sulphate)
6. concentrationconcentrated in vacuo
7. customto remove DMF traces
8. custompurified by chromatography
9. washeluting with 0-15% methanol/dichloromethane