Dimethylformamide → Methyl 3-(2-formylpyrrol-1-yl)-4-hydroxybenzoate

HRID 399837Notes

Reaction equation

HRID 399837 reaction equation
P(Cl)(Cl)(Cl)=O.CN(C)[CH:8]=[O:9].C([O:14][C:15]1[CH:24]=[CH:23][C:18]([C:19]([O:21][CH3:22])=[O:20])=[CH:17][C:16]=1[N:25]1[CH:29]=[CH:28][CH:27]=[CH:26]1)(=O)C>O>[CH:8]([C:29]1[N:25]([C:16]2[CH:17]=[C:18]([CH:23]=[CH:24][C:15]=2[OH:14])[C:19]([O:21][CH3:22])=[O:20])[CH:26]=[CH:27][CH:28]=1)=[O:9]

Participants

5

Reactant 3

HCID 6228DimethylformamideHCID 24813Phosphorus oxychlorideHCID 18945175Methyl 4-acetoxy-3-(pyrrol-1-yl)benzoate

Product 1

HCID 18945402Methyl 3-(2-formylpyrrol-1-yl)-4-hydroxybenzoate

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

To a solution of phosphorus oxychloride (8.3 ml) and N,N-dimethylformamide (70 ml) was added methyl 4-acetoxy-3-(pyrrol-1-yl)benzoate (11.7 g) at ambient temperature and the mixture was stirred for 20 hours at the same temperature. The reaction mixture was poured into water and extracted with ethyl acetate. The extract layer was washed with water, dried over magnesium sulfate and evaporated in vacuo. The residue was dissolved in tetrahydrofuran. To the solution was added 28% methanolic sodium methoxide (9.7 ml) under ice-cooling and the mixture was stirred for 30 minutes at the same temperature. To the mixture was added acetic acid (6 ml) and evaporated in vacuo. To the residue was added a mixture of ethyl acetate and water, and adjusted to pH 7 with 20% aqueous potassium carbonate solution. The separated organic layer was washed with water, dried over magnesium sulfate and evaporated in vacuo. The residue was crystallized from toluene, collected by filtration and the precipitate was washed with ether to give methyl 3-(2-formylpyrrol-1-yl)-4-hydroxybenzoate (7.89 g).

Workup

  1. extractionextracted with ethyl acetate
  2. washThe extract layer was washed with water
  3. dry with materialdried over magnesium sulfate
  4. customevaporated in vacuo
  5. dissolutionThe residue was dissolved in tetrahydrofuran
  6. additionTo the solution was added 28% methanolic sodium methoxide (9.7 ml) under ice-
  7. temperaturecooling
  8. stirringthe mixture was stirred for 30 minutes at the same temperature
  9. additionTo the mixture was added acetic acid (6 ml)
  10. customevaporated in vacuo
  11. additionTo the residue was added
  12. additiona mixture of ethyl acetate and water
  13. washThe separated organic layer was washed with water
  14. dry with materialdried over magnesium sulfate
  15. customevaporated in vacuo
  16. customThe residue was crystallized from toluene
  17. filtrationcollected by filtration
  18. washthe precipitate was washed with ether

Sources & evidence

ORD record
ord-8befd7ae65ea49639c1c98f00d8892a8
Source dataset
uspto-grants-1998_10
Patent number
US05824691

Reaction notes

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