Aluminium lithium hydride → HCID 86662721, compound

HRID 2090942Notes

Reaction equation

HRID 2090942 reaction equation
[CH3:1][O:2][C:3]1[CH:4]=[C:5]([N:9]2[CH:13]=[C:12]([CH3:14])[C:11]([C:15](OCC)=[O:16])=[N:10]2)[CH:6]=[CH:7][CH:8]=1.[H-].[Al+3].[Li+].[H-].[H-].[H-]>O1CCCC1.C1(C)C=CC=CC=1.[O-2].[O-2].[Mn+4]>[CH3:1][O:2][C:3]1[CH:4]=[C:5]([N:9]2[CH:13]=[C:12]([CH3:14])[C:11]([CH:15]=[O:16])=[N:10]2)[CH:6]=[CH:7][CH:8]=1

Participants

6

Reactant 2

HCID 21226445Aluminium lithium hydrideHCID 66777841HCID 66777841, compound2×

Product 1

HCID 86662721HCID 86662721, compoundYield 54%

Reagents, catalysts & solvents 3

HCID 178418406HCID 178418406, compoundCatalystHCID 1140TolueneSolventHCID 8028TetrahydrofuranSolvent2×

Procedure

A solution (5 mL) of ethyl 1-(3-methoxyphenyl)-4-methyl-1H-pyrazole-3-carboxylate (1.9 g) synthesized in the above-mentioned (1) in tetrahydrofuran was added to an ice-cooled solution (20 mL) of lithium aluminum hydride (0.29 g) in tetrahydrofuran. The ice bath was removed, and the reaction mixture was stirred at room temperature for 1 hr. The mixture was ice-cooled again, and water (0.76 mL), 1N aqueous sodium hydroxide solution (3.8 mL) and water (0.76 mL) were successively added dropwise to quench the reaction. The residue was filtered through celite, and the filtrate was concentrated under reduced pressure to give a crude product (0.99 g) of 1-(3-methoxyphenyl)-4-methyl-1H-pyrazole-3-methanol as a pale-yellow oil. This was dissolved in toluene (15 mL), manganese dioxide (0.32 g) was added, and the mixture was heated under reflux with a Dean-Stark trap for 1 hr. The reaction mixture was allowed to cool to room temperature, and manganese dioxide was collected by filtration. The filtrate was concentrated under reduced pressure to give the title object compound (0.84 g, 54%) as a yellow solid.

Workup

  1. customThe ice bath was removed
  2. temperaturecooled again
  3. additionwater (0.76 mL), 1N aqueous sodium hydroxide solution (3.8 mL) and water (0.76 mL) were successively added dropwise
  4. customto quench
  5. customthe reaction
  6. filtrationThe residue was filtered through celite
  7. concentrationthe filtrate was concentrated under reduced pressure
  8. customto give a crude product (0.99 g) of 1-(3-methoxyphenyl)-4-methyl-1H-pyrazole-3-methanol as a pale-yellow oil
  9. temperaturethe mixture was heated
  10. temperatureunder reflux with a Dean-Stark trap for 1 hr
  11. temperatureto cool to room temperature
  12. filtrationmanganese dioxide was collected by filtration
  13. concentrationThe filtrate was concentrated under reduced pressure

Sources & evidence

ORD record
ord-048dfb26e20d4a59be1f2bef14fa5a05
Source dataset
uspto-grants-2013_05
Patent number
US08436043B2

Reaction notes

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