4-nitro-1H-pyrazole → 1-(Cyclopropylmethyl)-4-nitro-1H-pyrazole

HRID 1478052Notes

Reaction equation

HRID 1478052 reaction equation
[N+:1]([C:4]1[CH:5]=[N:6][NH:7][CH:8]=1)([O-:3])=[O:2].[H-].[Na+].Br[CH2:12][CH:13]1[CH2:15][CH2:14]1>CN(C)C=O.O>[CH:13]1([CH2:12][N:6]2[CH:5]=[C:4]([N+:1]([O-:3])=[O:2])[CH:8]=[N:7]2)[CH2:15][CH2:14]1

Participants

6

Reactant 3

HCID 163764-nitro-1H-pyrazoleHCID 24758Sodium hydrideHCID 81503Bromomethylcyclopropane

Product 1

HCID 510000071-(Cyclopropylmethyl)-4-nitro-1H-pyrazoleYield 98.9%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6228DimethylformamideSolvent

Procedure

To a solution of 4-nitro-1H-pyrazole (5.05 g, 44.7 mmol) in N,N-dimethylformamide (250 mL) was added sodium hydride (2.7 g, 68 mmol, 60% mineral oil suspension) at 0° C. in portions and then followed by bromomethylcyclopropane (6.5 mL, 67 mmol) dropwise at same temperature. The mixture was stirred at room temperature for 4 h and diluted with water (300 mL) and extracted with EtOAc (300 mL×3). The combined organic phases were washed with brine (500 mL), dried over anhydrous Na2SO4, filtered and concentrated in vacuo. The residue was purified by silica gel column chromatography (EtOAc/PE (v/v)=1/50 to 1/20) to give the product as yellow oil (7.38 g, 98.9%).

Workup

  1. extractionextracted with EtOAc (300 mL×3)
  2. washThe combined organic phases were washed with brine (500 mL)
  3. dry with materialdried over anhydrous Na2SO4
  4. filtrationfiltered
  5. concentrationconcentrated in vacuo
  6. customThe residue was purified by silica gel column chromatography (EtOAc/PE (v/v)=1/50 to 1/20)

Sources & evidence

ORD record
ord-e69af5fe255a4488b98255c9ee657866
Source dataset
uspto-grants-2016_08
Patent number
US09403801B2

Reaction notes

Loading…