Acetone → Methyl 4,5-dibromo-3-(1-methylethoxy)-1-methyl-1H-pyrrole-2-carboxylate

HRID 621803Notes

Reaction equation

HRID 621803 reaction equation
[Br:1][C:2]1[C:3]([OH:13])=[C:4]([C:9]([O:11][CH3:12])=[O:10])[N:5]([CH3:8])[C:6]=1[Br:7].C(=O)([O-])[O-].[K+].[K+].[CH3:20][C:21]([CH3:23])=O>CN(C=O)C>[Br:1][C:2]1[C:3]([O:13][CH:21]([CH3:23])[CH3:20])=[C:4]([C:9]([O:11][CH3:12])=[O:10])[N:5]([CH3:8])[C:6]=1[Br:7]

Participants

5

Reactant 3

HCID 180AcetoneHCID 11430Potassium CarbonateHCID 54697145Methyl 4,5-dibromo-3-hydroxy-1-methyl-1H-pyrrole-2-carboxylate

Product 1

HCID 14154272Methyl 4,5-dibromo-3-(1-methylethoxy)-1-methyl-1H-pyrrole-2-carboxylate

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

Methyl 4,5-dibromo-3-hydroxy-1-methyl-1H-pyrrole- 2-carboxylate (9.6 g, 0.03 moles) and potassium carbonate (5.0 g, 0.036 moles) are stirred in a mixture of acetone (100 mL) and DMF (15 mL) and heated to reflux under argon. After 22 hours the solvent is removed under reduced pressure and the residue is partitioned between CH2Cl2 (500 mL) and water (400 mL). The layers are separated and the aqueous phase is extracted with CH2Cl2 (300 mL). The combined organic extracts are washed with saturated brine (2×300 mL) and dried over MgSO4. Removal of the solvent under reduced pressure afforded the crystalline product (10.6 g); mp 42°-45° C.

Workup

  1. temperatureheated
  2. temperatureto reflux under argon
  3. customAfter 22 hours the solvent is removed under reduced pressure
  4. customthe residue is partitioned between CH2Cl2 (500 mL) and water (400 mL)
  5. customThe layers are separated
  6. extractionthe aqueous phase is extracted with CH2Cl2 (300 mL)
  7. washThe combined organic extracts are washed with saturated brine (2×300 mL)
  8. dry with materialdried over MgSO4
  9. customRemoval of the solvent under reduced pressure

Sources & evidence

ORD record
ord-f193b0d8c5294cf489d474287177b90c
Source dataset
uspto-grants-1989_04
Patent number
US04824958

Reaction notes

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