Dimethyl Sulfate → HCID 59105415, compound

HRID 653828Notes

Reaction equation

HRID 653828 reaction equation
[CH2:1]([O:8][C:9]1[C:10]([CH3:20])=[N:11][N:12]([CH3:19])[C:13]=1[CH2:14][C:15]([O:17][CH3:18])=[O:16])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[CH:21]([O:23][CH3:24])=O.[H-].[Na+].C(=O)([O-])[O-].[K+].[K+].S(OC)(OC)(=O)=O>CN(C=O)C>[CH2:1]([O:8][C:9]1[C:10]([CH3:20])=[N:11][N:12]([CH3:19])[C:13]=1/[C:14](=[CH:21]\[O:23][CH3:24])/[C:15]([O:17][CH3:18])=[O:16])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Participants

7

Reactant 5

HCID 6497Dimethyl SulfateHCID 7865Methyl formateHCID 11430Potassium CarbonateHCID 24758Sodium hydrideHCID 54077336HCID 54077336, compound

Product 1

HCID 59105415HCID 59105415, compound

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent3×

Procedure

A solution of methyl (4-benzyloxy-1,3-dimethyl-pyrazol-5-yl)acetate (2.5 g, 9.1 mmol) and methyl formate (15 g, 250 mmol) in anhydrous DMF (10 ml) was added dropwise to a suspension of sodium hydride (60% dispersion in oil) (0.55 g, 13.8 mmol) in anhydrous DMF (5 ml), while the temperature being maintained below 10° C. by cooling on ice. After stirring at room temperature for 2 hours, the low boiling substances were removed under reduced pressure. To the residue was added potassium carbonate (2.5 g, 18.1 mmol), dimethyl sulfate (2.3 g, 18.2 mmol), and DMF (5 ml) under ice-cooling. After stirring at room temperature for 3 hours, the mixture was distilled under reduced pressure to remove low boiling substances. The residue was diluted with ethyl acetate, successively washed with water, and saturated brine, dried over anhydrous sodium sulfate and concentrated under reduced pressure. The residue was chromatographed over silica gel (eluent; ethyl acetate/n-hexane=1:1) to obtain (E)-methyl 2-(4-benzyloxy-1,3-dimethylpyrazol-5-yl)-3-methoxyacrylate (compound No. 1 in the Table 1) as a clear oil (2.1 g, 73%). Corresponding compound in Z-form (compound No. 2 in the Table 1) was also produced by the above reaction and recovered from the column.

Workup

  1. temperaturebeing maintained below 10° C.
  2. temperatureby cooling on ice
  3. customthe low boiling substances were removed under reduced pressure
  4. temperaturecooling
  5. stirringAfter stirring at room temperature for 3 hours
  6. distillationthe mixture was distilled under reduced pressure
  7. customto remove low boiling substances
  8. additionThe residue was diluted with ethyl acetate
  9. washsuccessively washed with water, and saturated brine
  10. dry with materialdried over anhydrous sodium sulfate
  11. concentrationconcentrated under reduced pressure
  12. customThe residue was chromatographed over silica gel (eluent; ethyl acetate/n-hexane=1:1)

Sources & evidence

ORD record
ord-d472b5c549f649fba0a6c3dc25e1ef86
Source dataset
uspto-grants-1992_07
Patent number
US05128481

Reaction notes

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