Citric Acid → 1-Methyl-5-phenoxy-1H-pyrazole-4-carboxylic acid ethyl ester

HRID 1778196Notes

Reaction equation

HRID 1778196 reaction equation
[C:1]1([OH:7])[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.C([O-])([O-])=O.[K+].[K+].[CH2:14]([O:16][C:17]([C:19]1[CH:20]=[N:21][N:22]([CH3:25])[C:23]=1Br)=[O:18])[CH3:15].C(O)(=O)CC(CC(O)=O)(C(O)=O)O>CC(N(C)C)=O>[CH2:14]([O:16][C:17]([C:19]1[CH:20]=[N:21][N:22]([CH3:25])[C:23]=1[O:7][C:1]1[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1)=[O:18])[CH3:15]

Participants

6

Reactant 4

HCID 311Citric AcidHCID 996PhenolHCID 11430Potassium CarbonateHCID 53302113Ethyl 5-Bromo-1-methyl-1H-pyrazole-4-carboxylate

Product 1

HCID 867185501-Methyl-5-phenoxy-1H-pyrazole-4-carboxylic acid ethyl ester

Reagents, catalysts & solvents 1

HCID 31374DimethylacetamideSolvent

Conditions

Temperature
140 °C

Procedure

Phenol (30.3 g; 322 mmol) is dissolved in DMA and K2CO3 (88.9 g; 643 mmol) is added portion wise. It is stirred for 10 minutes, then 5-Bromo-1-methyl-1H-pyrazole-4-carboxylic acid ethyl ester (50.0 g; 215 mmol) is dropped to the reaction mixture and heated up to 140° C. for 16 hours. A 10% citric acid solution is added and extracted with DCM. The organic layer is washed with sodium bicarbonate and brine, then dried and purified through column chromatography.

Workup

  1. extractionextracted with DCM
  2. washThe organic layer is washed with sodium bicarbonate and brine
  3. customdried
  4. custompurified through column chromatography

Sources & evidence

ORD record
ord-61f03395f4d543b88452051962bba683
Source dataset
uspto-grants-2016_02
Patent number
US09266891B2

Reaction notes

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