Carbon Dioxide → 1-Piperazinecarboxylic acid, ethyl ester

HRID 1580553Notes

Reaction equation

HRID 1580553 reaction equation
CN(C)S(C1C=[C:10]2[C:11]([O:13][C:14](=[O:16])[NH:15][C:9]2=[CH:8]C=1)=O)(=O)=O.COC([N:23]1CCN[CH2:25][CH2:24]1)=O.C(=O)=O>O1CCOCC1>[CH2:11]([O:13][C:14]([N:15]1[CH2:9][CH2:8][NH:23][CH2:24][CH2:25]1)=[O:16])[CH3:10]

Participants

5

Reactant 3

HCID 280Carbon DioxideHCID 142729Methyl piperazine-1-carboxylateHCID 53701294HCID 53701294, compound

Product 1

HCID 84311-Piperazinecarboxylic acid, ethyl ester

Reagents, catalysts & solvents 1

HCID 312751,4-DioxaneSolvent

Procedure

13.5 g of 5-(dimethylsulphamoyl)-isatoic acid anhydride and 70 ml of absolute dioxane are gently warmed. As soon as the reaction mixture has reached 40°C, a solution of 8.3 g of N-methoxycarbonylpiperazine is added dropwise and the mixture is then heated further, an evolution of carbon dioxide setting in at about 70°C. The mixture is heated under reflux for a further hour and allowed to cool somewhat, insoluble matter is filtered off and the filtrate is concentrated under reduced pressure. The colourless crystals which are precipitated are filtered off with suction and recrystallised from 350 ml of methanol. 13.1 g of 1-[5-dimethylsulphamoyl)-anthraniloyl]-4-ethoxycarbonyl-piperazine, melting point 202°-204°C, are thus obtained.

Workup

  1. customhas reached 40°C
  2. temperaturethe mixture is then heated further
  3. customin at about 70°C
  4. temperatureThe mixture is heated
  5. temperatureunder reflux for a further hour
  6. temperatureto cool somewhat
  7. filtrationinsoluble matter is filtered off
  8. concentrationthe filtrate is concentrated under reduced pressure
  9. customThe colourless crystals which are precipitated
  10. filtrationare filtered off with suction
  11. customrecrystallised from 350 ml of methanol

Sources & evidence

ORD record
ord-a35adcb940b14840bc58f9c2e96b657a
Source dataset
uspto-grants-1976_01
Patent number
US03933802

Reaction notes

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