Sodium hydride → (3-Nitro-pyrazol-1-yl)-propionic acid tert-butyl ester

HRID 545996Notes

Reaction equation

HRID 545996 reaction equation
[N+:1]([C:4]1[CH:8]=[CH:7][NH:6][N:5]=1)([O-:3])=[O:2].[H-].[Na+].[C:11]([O:15][C:16](=[O:20])[CH2:17][CH2:18]Br)([CH3:14])([CH3:13])[CH3:12]>CN(C)C=O>[C:11]([O:15][C:16](=[O:20])[CH:17]([N:6]1[CH:7]=[CH:8][C:4]([N+:1]([O-:3])=[O:2])=[N:5]1)[CH3:18])([CH3:14])([CH3:13])[CH3:12]

Participants

5

Reactant 3

HCID 24758Sodium hydrideHCID 256128tert-Butyl 3-bromopropionateHCID 178526745HCID 178526745, compound

Product 1

HCID 65814351(3-Nitro-pyrazol-1-yl)-propionic acid tert-butyl esterYield 57%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

To a solution of 3-nitro-1H-pyrazole (prepared in example 3, 2.00 g, 17.70 mmol) in anhydrous N,N-dimethylformamide (30 mL), a 60% dispersion of sodium hydride in mineral oil (778 mg, 19.50 mmol) was added while stirring under nitrogen. After the effervescence ceased and the mixture was stirred for additional 30 min, 3-bromo-propionic acid tert-butyl ester (3.25 mL, 19.50 mmol) was added. The mixture was continued to stir under nitrogen for an additional 2 h. The solvent was removed in vacuo and purification by ISCO flash column chromatography (Teledyne Isco RediSep Flash Column 40 g; 2% methanol/methylene chloride to 5% methanol/methylene chloride) to afford (3-nitro-pyrazol-1-yl)-propionic acid tert-butyl ester (2.30 g, 57%) as a yellow oil.

Workup

  1. stirringthe mixture was stirred for additional 30 min
  2. stirringto stir under nitrogen for an additional 2 h
  3. customThe solvent was removed in vacuo and purification by ISCO flash column chromatography (Teledyne Isco RediSep Flash Column 40 g; 2% methanol/methylene chloride to 5% methanol/methylene chloride)

Sources & evidence

ORD record
ord-5236555aecc24dcb83597f4416241047
Source dataset
uspto-grants-2011_05
Patent number
US07935699B2

Reaction notes

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