Hydrochloric Acid → 4-(2,3-Dichlorophenyl)-1H-pyrrole-3-carboxylic acid

HRID 703269Notes

Reaction equation

HRID 703269 reaction equation
[C:1]([C:5]1[C:9]([C:10]2[CH:15]=[CH:14][CH:13]=[C:12]([Cl:16])[C:11]=2[Cl:17])=[CH:8][NH:7][CH:6]=1)([O:3]C)=[O:2].Cl>CO>[Cl:17][C:11]1[C:12]([Cl:16])=[CH:13][CH:14]=[CH:15][C:10]=1[C:9]1[C:5]([C:1]([OH:3])=[O:2])=[CH:6][NH:7][CH:8]=1

Participants

4

Reactant 2

HCID 313Hydrochloric AcidHCID 15087831Methyl 4-(2,3-dichlorophenyl)-1H-pyrrole-3-carboxylate2×

Product 1

HCID 152390934-(2,3-Dichlorophenyl)-1H-pyrrole-3-carboxylic acid

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Conditions

Temperature
70 °C

Procedure

3.2 g of the 3-carbomethoxy-4-(2,3-dichlorophenyl)pyrrole obtained in (a) and 40 ml of a 1:1 mixture of methanol and 5N HCl are stirred for hours at 70° C. After it has coled to room temperature, the reaction mixture is poured onto ice and extracted with ethyl acetate. The ester phase is in turn extracted with 10% sodium hydroxide solution. The aqueous extract is washed twice with ethyl acetate, acidified with hydrochloric acid and extracted with ethyl acetate. The organic phase is washed with water, dried over magnesium sulfate and filtered. The filtrate is concentrated by evaporation and the resultant 4-(2,3-dichlorophenyl)pyrrole-3-carboxylic acid melts at 180°-182° C.

Workup

  1. customhas coled to room temperature
  2. additionthe reaction mixture is poured onto ice
  3. extractionextracted with ethyl acetate
  4. extractionextracted with 10% sodium hydroxide solution
  5. extractionThe aqueous extract
  6. washis washed twice with ethyl acetate
  7. extractionextracted with ethyl acetate
  8. washThe organic phase is washed with water
  9. dry with materialdried over magnesium sulfate
  10. filtrationfiltered
  11. concentrationThe filtrate is concentrated by evaporation

Sources & evidence

ORD record
ord-3b301036cbf24437ac64e34a17bb971c
Source dataset
uspto-grants-1991_01
Patent number
US04981990

Reaction notes

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