p-Chlorophenacyl bromide → methyl 4-bromo-1-[2-(4-chlorophenyl)-2-oxoethyl]-1H-pyrrole-2-carboxylate

HRID 1910911Notes

Reaction equation

HRID 1910911 reaction equation
[Br:1][C:2]1[CH:3]=[C:4]([C:7]([O:9][CH3:10])=[O:8])[NH:5][CH:6]=1.Br[CH2:12][C:13]([C:15]1[CH:20]=[CH:19][C:18]([Cl:21])=[CH:17][CH:16]=1)=[O:14].CC(C)([O-])C.[K+]>CN(C=O)C.O>[Br:1][C:2]1[CH:3]=[C:4]([C:7]([O:9][CH3:10])=[O:8])[N:5]([CH2:12][C:13]([C:15]2[CH:20]=[CH:19][C:18]([Cl:21])=[CH:17][CH:16]=2)=[O:14])[CH:6]=1

Participants

6

Reactant 3

HCID 68303p-Chlorophenacyl bromideHCID 2763594Methyl 4-bromo-1H-pyrrole-2-carboxylateHCID 23665647Potassium tert-butoxide

Product 1

HCID 67366602methyl 4-bromo-1-[2-(4-chlorophenyl)-2-oxoethyl]-1H-pyrrole-2-carboxylateYield 55.6%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6228DimethylformamideSolvent

Procedure

Methyl 4-bromo-1H-pyrrole-2-carboxylate (250 mg, 1.23 mmol) and 2-bromo-1-(4-chloro-phenyl)-ethanone (315 mg, 1.35 mmol) were dissolved in DMF (50 mL). The reaction mixture was cooled to 0° C. before potassium tert-butoxide (125 mg, 1.11 mmol) was added to the reaction mixture in small portions. The resulting suspension was allowed to warm to room temperature then stirred for 10 min. The reaction mixture was diluted with water (100 mL) and extracted with CH2Cl2 (3×100 mL). The organic layers were combined, dried and concentrated in vacuo to give a residue that was purified using flash chromatography (Biotage SP4, 40 g cartridge, 0-15% EtOAc gradient in n-hexanes) to give the target compound methyl 4-bromo-1-[2-(4-chlorophenyl)-2-oxoethyl]-1H-pyrrole-2-carboxylate (244 mg) contaminated with an impurity. The mixture was used in the next step without further purification.

Workup

  1. additionwas added to the reaction mixture in small portions
  2. extractionextracted with CH2Cl2 (3×100 mL)
  3. customdried
  4. concentrationconcentrated in vacuo
  5. customto give a residue that
  6. customwas purified

Sources & evidence

ORD record
ord-b7a43d2969f04b9cbf1fe438c1cb3654
Source dataset
uspto-grants-2013_12
Patent number
US08604034B2

Reaction notes

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