Methanesulfonic Acid → Ethyl trans-2,5-dimethyl-1-piperazinecarboxylate

HRID 553822Notes

Reaction equation

HRID 553822 reaction equation
CS(O)(=O)=O.[CH3:6][C@H:7]1[CH2:12][NH:11][C@H:10]([CH3:13])[CH2:9][NH:8]1.C([O-])(=O)C.[K+].Cl[C:20]([O:22][CH2:23][CH3:24])=[O:21]>O.C1COCC1.CCO>[CH2:23]([O:22][C:20]([N:8]1[CH2:9][C@@H:10]([CH3:13])[NH:11][CH2:12][C@@H:7]1[CH3:6])=[O:21])[CH3:24]

Participants

8

Reactant 4

HCID 6395Methanesulfonic AcidHCID 10928Ethyl chloroformateHCID 2206722,5-Dimethylpiperazine, trans-HCID 517044Potassium Acetate2×

Product 1

HCID 10607598Ethyl trans-2,5-dimethyl-1-piperazinecarboxylate

Reagents, catalysts & solvents 3

HCID 702EthanolSolventHCID 962WaterSolventHCID 8028TetrahydrofuranSolvent

Procedure

Methanesulfonic acid (1.136 ml) dissolved in water (1 ml) was added to trans-2,5-dimethylpiperazine (1 g). It was cooled down in an ice bath so that the temperature did not rise above 40° C. At 25° C., EtOH (1.2 ml) was added to the mixture and the pH was adjusted to 4-5 by adding a 50% solution of potassium acetate. Finally, ethyl chloroformate dissolved in THF was added. The pH was again adjusted to 4 by adding a 50% solution of potassium acetate. The mixture was stirred for another hour at RT and evaporated off. The residue was diluted with EA, the org. phase was separated, washed with a 1M HCl solution. The aq. layers were basified with a NaOH solution till pH 10 and extracted with EA. The combined org. layers were dried (Na2SO4) and evaporated off. 740 mg of the desired compound were obtained.

Workup

  1. temperatureIt was cooled down in an ice bath so that the temperature
  2. customdid not rise above 40° C
  3. additionwas added
  4. customevaporated off
  5. additionThe residue was diluted with EA
  6. customphase was separated
  7. washwashed with a 1M HCl solution
  8. extractionextracted with EA
  9. dry with materiallayers were dried (Na2SO4)
  10. customevaporated off

Sources & evidence

ORD record
ord-a5b8242532af4ff4991de1c15855178a
Source dataset
uspto-grants-2011_11
Patent number
US08048881B2

Reaction notes

Loading…