Lithium Hydroxide → 3-Chloro-4H-thieno[3,2-b]pyrrole-5-carboxylic acid

HRID 1178441Notes

Reaction equation

HRID 1178441 reaction equation
[Cl:1][C:2]1[C:6]2[NH:7][C:8]([C:10]([O:12]C)=[O:11])=[CH:9][C:5]=2[S:4][CH:3]=1.[OH-].[Li+]>CO>[C:10]([C:8]1[NH:7][C:6]2[C:2]([Cl:1])=[CH:3][S:4][C:5]=2[CH:9]=1)([OH:12])=[O:11]

Participants

4

Reactant 2

HCID 3939Lithium HydroxideHCID 21906846HCID 21906846, compound

Product 1

HCID 219068633-Chloro-4H-thieno[3,2-b]pyrrole-5-carboxylic acidYield 100%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

3-Chloro-5-methoxycarbonyl-4H-thieno[3,2-b]pyrrole (Method 4; 0.61 g, 2.83 mmol) was taken up in MeOH (10 ml) and was heated under reflux. Aqueous lithium hydroxide (2.0 M, 3.0 ml, 6.0 mmol) was added portionwise over 45 minutes. The mixture was heated under reflux for 30 minutes before being cooled and concentrated. Water (20 ml) was added and the solution was neutralised using aqueous hydrochloric acid (2.0 M, 3.0 ml). The solution was extracted using EtOAc, and the combined organic layers were concentrated to afford the title compound as a yellow solid (0.57 g, 100%). NMR: 12.4 (1H, br), 7.4 (1H, s), 7.0 (1H, s); m/z 200.3.

Workup

  1. temperaturewas heated
  2. temperatureunder reflux
  3. temperatureThe mixture was heated
  4. temperatureunder reflux for 30 minutes
  5. temperaturebefore being cooled
  6. concentrationconcentrated
  7. additionWater (20 ml) was added
  8. extractionThe solution was extracted
  9. concentrationthe combined organic layers were concentrated

Sources & evidence

ORD record
ord-c54b08d74fcc49378028ae87b59fdc12
Source dataset
uspto-grants-2007_10
Patent number
US07276517B2

Reaction notes

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