Potassium Carbonate → 1-Acetyl-4-(3-bromopropyl)piperazine

A mixture of 1-(1-piperazinyl)-1-ethanone (6.7 g, 0.052 mol), dibromopropane (330 mL, excess) and K2CO3 (10.2 g, 0.079 mol) was stirred at rt for 4 h. The mixture was washed with 4×100 mL of water, and the organic phase (diluted with DCM) was acidified with aqueous hydrobromic acid (7 mL of 62% HBr dissolved in 150 mL of water). The organic layer was separated and washed with water (2×50 mL). The combined water layers were extracted with ether, neutralised (to pH 7) with 13 mL of 10 M NaOH, and then extracted with DCM. The combined organic layers were dried and concentrated in vacuo to give 4.1 g (32%) of the title compound.

1. washThe mixture was washed with 4×100 mL of water
2. additionthe organic phase (diluted with DCM)
3. customThe organic layer was separated
4. washwashed with water (2×50 mL)
5. extractionThe combined water layers were extracted with ether, neutralised (to pH 7) with 13 mL of 10 M NaOH
6. extractionextracted with DCM
7. customThe combined organic layers were dried
8. concentrationconcentrated in vacuo

ORD record

ord-27b4e493c505400698912c36247f9abc

Source dataset

uspto-grants-2003_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06559143B1