Hydrochloric Acid → 2-butyl-1,4-dihydropyrrolo[3,4-b]indol-3(2H)-one

HRID 2163214Notes

Reaction equation

HRID 2163214 reaction equation
[CH2:1]([N:5]1[CH2:9][CH:8]([C:10](OC)=O)[C:7](=O)[C:6]1=[O:15])[CH2:2][CH2:3][CH3:4].Cl.C([O-])(=O)C.[Na+].[C:22]1([NH:28]N)C=[CH:26][CH:25]=[CH:24][CH:23]=1>O.C(O)C>[CH2:1]([N:5]1[CH2:9][C:8]2[C:10]3[CH:26]=[CH:25][CH:24]=[CH:23][C:22]=3[NH:28][C:7]=2[C:6]1=[O:15])[CH2:2][CH2:3][CH3:4]

Participants

7

Reactant 4

HCID 313Hydrochloric AcidHCID 7516PhenylhydrazineHCID 517045Sodium AcetateHCID 706043411-n-Butyl-4-carbomethoxy-2,3-dioxopyrrolidine

Product 1

HCID 213202522-butyl-1,4-dihydropyrrolo[3,4-b]indol-3(2H)-one

Reagents, catalysts & solvents 2

HCID 702EthanolSolventHCID 962WaterSolvent

Procedure

1-n-Butyl-4-carbomethoxy-2,3-dioxopyrrolidine, 107 g., [Southwick and Owellen, J. Org. Chem. 25(1960)1133] is heated to boiling in a mixture of 600 ml. of a twenty percent aqueous hydrochloric acid solution and about 100 ml. of ninety-five percent ethanol. Solids dissolved in about ten minutes to give a yellow solution. After one hour of heating, the flask is cooled to about room temperature. Sodium acetate is then added to neutralize the reaction mixture to a pH of 4-5. In addition about 500 ml. of water is added during the neutralization to insure that most materials will remain in solution. Phenylhydrazine, 54 g., is then washed into the stirred mixture with methanol, 20 ml. The phenyl hydrazone starts to separate immediately, and is collected after ten minutes of cooling and stirring. The material is dissolved in 200 ml. of acetic acid at 65° and treated with 100 ml. of concentrated hydrochloric acid. A strong exotherm takes the temperature up to about 110° which causes vigorous refluxing. Filtration of the cooled slurry yields 78 g. of the title compound, m.p. 215°-218° sinters at 210°. Dilution of the filtrate with water gives additional product, 7 g., m.p. after recrystallization from methanol: 216°-218°.

Workup

  1. temperature, [Southwick and Owellen, J. Org. Chem. 25(1960)1133] is heated
  2. additionto boiling in a mixture of 600 ml
  3. dissolutionSolids dissolved in about ten minutes
  4. customto give a yellow solution
  5. temperatureAfter one hour of heating
  6. temperaturethe flask is cooled to about room temperature
  7. additionIn addition about 500 ml
  8. wash, is then washed into the stirred mixture with methanol, 20 ml
  9. customto separate immediately
  10. customis collected after ten minutes
  11. temperatureof cooling
  12. dissolutionThe material is dissolved in 200 ml
  13. additionof acetic acid at 65° and treated with 100 ml
  14. customup to about 110° which
  15. filtrationFiltration of the cooled slurry
  16. customyields 78 g

Sources & evidence

ORD record
ord-b7a096a7ebfc4aeab1fa412348e45b01
Source dataset
uspto-grants-1979_01
Patent number
US04132792

Reaction notes

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