Potassium Permanganate → 2-Methyl 1H-pyrrole-2,4-dicarboxylate

HRID 2375789Notes

Reaction equation

HRID 2375789 reaction equation
[CH3:1][O:2][C:3]([C:5]1[NH:6][CH:7]=[C:8]([CH:10]=[O:11])[CH:9]=1)=[O:4].[O-:12][Mn](=O)(=O)=O.[K+].OS([O-])=O.[Na+]>CC(C)=O.O>[CH3:1][O:2][C:3]([C:5]1[NH:6][CH:7]=[C:8]([C:10]([OH:12])=[O:11])[CH:9]=1)=[O:4]

Participants

5

Reactant 3

HCID 516875Potassium PermanganateHCID 640310methyl 4-formyl-1H-pyrrole-2-carboxylateHCID 23665763Sodium Bisulfite

Product 1

HCID 124599712-Methyl 1H-pyrrole-2,4-dicarboxylate

Reagents, catalysts & solvents 1

HCID 18366337Propan-2-one--water (1/1)Solvent2×

Procedure

To a solution of 4-formyl-1H-pyrrole-2-carboxylic acid methyl ester (589 mg) in acetone/water (50 mL, 1:1) was added a solution of KMnO4 in acetone/water (70 mL, 1:1) dropwise within one hour. The mixture was stirred for 3 h at RT whereupon it was poured into a solution of NaHSO3 (10% in 1 N HCl, 100 mL). The resulting mixture was extracted with ethyl acetate. The combined organic phases were washed with water and extracted with 2N aqueous K2CO3 solution. The basic aqueous phase was acidified with 2N HCl and extracted with ethyl acetate The combined organic phases were dried (MgSO4) and concentrated in vacuo to provide 1H-pyrrole-2,4-dicarboxylic acid 2-methyl ester (530 mg) which was used directly in the next step.

Workup

  1. extractionThe resulting mixture was extracted with ethyl acetate
  2. washThe combined organic phases were washed with water
  3. extractionextracted with 2N aqueous K2CO3 solution
  4. extractionextracted with ethyl acetate The combined organic phases
  5. dry with materialwere dried (MgSO4)
  6. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-880698262f6d4940b1bcb8a5fc0aa5c2
Source dataset
uspto-grants-2008_12
Patent number
US07465806B2

Reaction notes

Loading…