Ethanol → ethyl 1-tert-butyl-5-(2-chlorophenyl)-1H-pyrazole-4-carboxylate

HRID 251934Notes

Reaction equation

HRID 251934 reaction equation
[Cl:1][C:2]1[CH:19]=[CH:18][CH:17]=[CH:16][C:3]=1[C:4]([C:6](=[CH:12][N:13](C)C)[C:7]([O:9][CH2:10][CH3:11])=[O:8])=O.Cl.[C:21]([NH:25]N)([CH3:24])([CH3:23])[CH3:22].C(O)C>O>[C:21]([N:25]1[C:4]([C:3]2[CH:16]=[CH:17][CH:18]=[CH:19][C:2]=2[Cl:1])=[C:6]([C:7]([O:9][CH2:10][CH3:11])=[O:8])[CH:12]=[N:13]1)([CH3:24])([CH3:23])[CH3:22]

Participants

5

Reactant 3

HCID 702EthanolHCID 81889tert-Butylhydrazine monohydrochlorideHCID 54509863Ethyl 2-(2-chlorobenzoyl)-3-dimethylaminopropenoate

Product 1

HCID 66853797ethyl 1-tert-butyl-5-(2-chlorophenyl)-1H-pyrazole-4-carboxylateYield 15.6%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

A mixture of 2.82 g of ethyl 2-(2-chlorobenzoyl)-3-(N,N-dimethylamino)acrylate (a compound described in JP-A 7-101940), 1.25 g of tert-butylhydrazine hydrochloride and 10 ml of ethanol was heated to reflux for 8 hours. After the reaction mixture was allowed to cool to room temperature, water was poured and the mixture was extracted with ethyl acetate. The organic layer was washed with water, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The resulting residue was subjected to silica gel column chromatography to obtain 0.48 g of ethyl 1-tert-butyl-5-(2-chlorophenyl)-1H-pyrazole-4-carboxylate of the formula:

Workup

  1. temperaturewas heated
  2. temperatureto reflux for 8 hours
  3. extractionthe mixture was extracted with ethyl acetate
  4. washThe organic layer was washed with water
  5. dry with materialdried over anhydrous sodium sulfate
  6. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-3ecd01727e114072985991f7de97e260
Source dataset
uspto-grants-2011_01
Patent number
US07867949B2

Reaction notes

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