Potassium Carbonate → 2-(3-Ethoxycarbonyl-propyl)-5-phenyl-2H-pyrazole-3-carboxylic acid methyl ester

HRID 241949Notes

Reaction equation

[CH3:1][O:2][C:3]([C:5]1[NH:6][N:7]=[C:8]([C:10]2[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=2)[CH:9]=1)=[O:4].Br[CH2:17][CH2:18][CH2:19][C:20]([O:22][CH2:23][CH3:24])=[O:21].C(=O)([O-])[O-].[K+].[K+]>C(#N)C>[CH3:1][O:2][C:3]([C:5]1[N:6]([CH2:17][CH2:18][CH2:19][C:20]([O:22][CH2:23][CH3:24])=[O:21])[N:7]=[C:8]([C:10]2[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=2)[CH:9]=1)=[O:4]

Participants

Conditions

Temperature: 60 °C

Procedure

5-Phenyl-2H-pyrazole-3-carboxylic acid methyl ester (9.10 g, 45.0 mmol) is taken up in 100 mL acetonitrile and heated to 60° C. Ethyl 4-bromobutanoate (8.78 g, 45.0 mmol) and potassium carbonate (8.09 g, 58.5 mmol) are added and the reaction mixture is heated to 85° C. and stirred under reflux for 5 h. The reaction mixture is filtered and the filtrate is concentrated under reduced pressure. The residue is taken up in water and extracted with ethyl acetate. The combined organic phases are dried over Na2SO4 and concentrated under reduced pressure. The residue is purified by flash column chromatography (silica gel, 8-40% ethyl acetate in heptane). Yield: 10.3 g. Rf (silica gel, 2% methanol in DCM)=0.41.

Workup

temperaturethe reaction mixture is heated to 85° C.
temperatureunder reflux for 5 h
filtrationThe reaction mixture is filtered
concentrationthe filtrate is concentrated under reduced pressure
extractionextracted with ethyl acetate
dry with materialThe combined organic phases are dried over Na2SO4
concentrationconcentrated under reduced pressure
customThe residue is purified by flash column chromatography (silica gel, 8-40% ethyl acetate in heptane)

Sources & evidence

ORD record: ord-dcc230be08e54b14889a2802800bb16d
Source dataset: uspto-grants-2014_02
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08653097B2

Reaction notes

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