Isopropyl iodide → 3-benzyloxy-4-(4-ethylbenzyl)-1-isopropyl-5-methyl-1H-pyrazole

HRID 2116475Notes

Reaction equation

HRID 2116475 reaction equation
[CH2:1]([O:8][C:9]1[C:13]([CH2:14][C:15]2[CH:20]=[CH:19][C:18]([CH2:21][CH3:22])=[CH:17][CH:16]=2)=[C:12]([CH3:23])[NH:11][N:10]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C(=O)([O-])[O-].[Cs+].[Cs+].[CH:30](I)([CH3:32])[CH3:31]>CN(C)C=O.O>[CH2:1]([O:8][C:9]1[C:13]([CH2:14][C:15]2[CH:16]=[CH:17][C:18]([CH2:21][CH3:22])=[CH:19][CH:20]=2)=[C:12]([CH3:23])[N:11]([CH:30]([CH3:32])[CH3:31])[N:10]=1)[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1

Participants

6

Reactant 3

HCID 6362Isopropyl iodide2×HCID 10796Cesium carbonate2×HCID 231036163-benzyloxy-4-(4-ethylbenzyl)-5-methyl-1H-pyrazole

Product 1

HCID 231036073-benzyloxy-4-(4-ethylbenzyl)-1-isopropyl-5-methyl-1H-pyrazoleYield 79%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6228DimethylformamideSolvent

Procedure

To a suspension of the thus obtained 3-benzyloxy-4-(4-ethylbenzyl)-5-methyl-1H-pyrazole (200 mg, 0.65 mmol) and cesium carbonate (1.06 g, 3.25 mmol) in N,N-dimethylformamide (4 mL), isopropyl iodide (350 mg, 2.06 mmol) was added dropwise at room temperature. After stirring at room temperature for 13 hours, additional cesium carbonate (1.06 g, 3.25 mmol) and isopropyl iodide (350 mg, 2.06 mmol) were added. After stirring at room temperature for an additional 3 hours, the reaction mixture was diluted with water and extracted with ethyl acetate. The resulting organic layer was washed with saturated aqueous sodium chloride and dried over anhydrous magnesium sulfate. After the solvent was distilled off under reduced pressure, the resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate=10:1) to give 3-benzyloxy-4-(4-ethylbenzyl)-1-isopropyl-5-methyl-1H-pyrazole (179 mg, 79%) as a light-brown oil.

Workup

  1. additionwas added dropwise at room temperature
  2. stirringAfter stirring at room temperature for an additional 3 hours
  3. extractionextracted with ethyl acetate
  4. washThe resulting organic layer was washed with saturated aqueous sodium chloride
  5. dry with materialdried over anhydrous magnesium sulfate
  6. distillationAfter the solvent was distilled off under reduced pressure
  7. customthe resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate=10:1)

Sources & evidence

ORD record
ord-fb91eb75df694626892a008379061629
Source dataset
uspto-grants-2008_10
Patent number
US07439232B2

Reaction notes

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