Lithium aluminum hydride → 2-ethyl-5-(4-fluoro-benzylamino)-2H-pyrazole-3-carbaldehyde

HRID 1754717Notes

Reaction equation

HRID 1754717 reaction equation
C[O:2][C:3]([C:5]1[N:6]([CH2:19][CH3:20])[N:7]=[C:8]([NH:10][CH2:11][C:12]2[CH:17]=[CH:16][C:15]([F:18])=[CH:14][CH:13]=2)[CH:9]=1)=O.[AlH4-].[Li+].O.O.O.O.O.O.O.O.O.O.S([O-])([O-])(=O)=O.[Na+].[Na+]>O1CCCC1>[CH2:19]([N:6]1[C:5]([CH:3]=[O:2])=[CH:9][C:8]([NH:10][CH2:11][C:12]2[CH:13]=[CH:14][C:15]([F:18])=[CH:16][CH:17]=2)=[N:7]1)[CH3:20]

Participants

5

Reactant 3

HCID 28112Lithium aluminum hydrideHCID 62649Sodium sulfate decahydrateHCID 576193832-ethyl-5-(4-fluoro-benzylamino)-2H-pyrazole-3-carboxylic acid methyl ester

Product 1

HCID 576192072-ethyl-5-(4-fluoro-benzylamino)-2H-pyrazole-3-carbaldehyde

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To 2-ethyl-5-(4-fluoro-benzylamino)-2H-pyrazole-3-carboxylic acid methyl ester (529, 1.00 g, 3.61 mol) in tetrahydrofuran (70.0 mL) under an atmosphere of nitrogen at room temperature, lithium tetrahydroaluminate (1.00 M of in tetrahydrofuran, 10.00 mL) was slowly added. The reaction was stirred at room temperature overnight, followed by slowly adding sodium sulfate decahydrate (15.0 g). After 2 hours, the reaction was filtered, concentrated and purified with silica gel column chromatography eluting with 20% to 100% ethyl acetate in hexane to give a yellow oil (530, 0.16 g, 18%). MS (ESI) [M+H+]+=248.2.

Workup

  1. waitAfter 2 hours
  2. filtrationthe reaction was filtered
  3. concentrationconcentrated
  4. custompurified with silica gel column chromatography
  5. washeluting with 20% to 100% ethyl acetate in hexane
  6. customto give a yellow oil (530, 0.16 g, 18%)

Sources & evidence

ORD record
ord-18ea33246ef74549a503805d2487dc02
Source dataset
uspto-grants-2015_10
Patent number
US09169250B2

Reaction notes

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