Methyl iodide → ethyl 3-acetyl-1-methyl-1H-pyrazole-5-carboxylate

HRID 925409Notes

Reaction equation

HRID 925409 reaction equation
[C:1]([C:4]1[NH:8][N:7]=[C:6]([C:9]([O:11][CH2:12][CH3:13])=[O:10])[CH:5]=1)(=[O:3])[CH3:2].[C:14]([O-])([O-])=O.[Cs+].[Cs+].CI.CCOC(C)=O>CN(C=O)C>[C:1]([C:4]1[CH:5]=[C:6]([C:9]([O:11][CH2:12][CH3:13])=[O:10])[N:7]([CH3:14])[N:8]=1)(=[O:3])[CH3:2]

Participants

6

Reactant 4

HCID 6328Methyl iodideHCID 8857Ethyl AcetateHCID 10796Cesium carbonateHCID 178468948HCID 178468948, compound

Product 1

HCID 71306158ethyl 3-acetyl-1-methyl-1H-pyrazole-5-carboxylateYield 68.8%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

To a solution of ethyl 5-acetyl-1H-pyrazole-3-carboxylate (0.050 g, 0.274 mmol) in DMF (3 mL), Cs2CO3 (0.134 g, 0.412 mmol) and methyl iodide (0.022 mL, 0.357 mmol) were added. The reaction was continued at r.t. overnight then AcOEt (20 mL) was added and the organic phase washed with water (20 mL). The aqueous fraction was extracted with AcOEt (20 mL). The organic fractions were combined, dried over Na2SO4, filtered, and concentrated in vacuo. Purification by flash chromatography on silica gel (eluant: AcOEt/hexane 2/8) provided 37 mg (68% yield) of ethyl 3-acetyl-1-methyl-1H-pyrazole-5-carboxylate.

Workup

  1. washthe organic phase washed with water (20 mL)
  2. extractionThe aqueous fraction was extracted with AcOEt (20 mL)
  3. dry with materialdried over Na2SO4
  4. filtrationfiltered
  5. concentrationconcentrated in vacuo
  6. customPurification by flash chromatography on silica gel (eluant: AcOEt/hexane 2/8)

Sources & evidence

ORD record
ord-f54d4408970d43aa9d1761d1996dbe2d
Source dataset
uspto-grants-2016_03
Patent number
US09284298B2

Reaction notes

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