Pyrazole → 1-[2-(4-nitrophenyl)ethyl]-1H-pyrazole

HRID 30687

Reaction equation

HRID 30687 reaction equation
Br[CH2:2][CH2:3][C:4]1[CH:9]=[CH:8][C:7]([N+:10]([O-:12])=[O:11])=[CH:6][CH:5]=1.[NH:13]1[CH:17]=[CH:16][CH:15]=[N:14]1.[OH-].[K+]>O>[N+:10]([C:7]1[CH:8]=[CH:9][C:4]([CH2:3][CH2:2][N:13]2[CH:17]=[CH:16][CH:15]=[N:14]2)=[CH:5][CH:6]=1)([O-:12])=[O:11]

Participants

5

Reactant 3

HCID 1048PyrazoleHCID 14797Potassium HydroxideHCID 792664-Nitrophenethyl bromide

Product 1

HCID 638109421-[2-(4-nitrophenyl)ethyl]-1H-pyrazoleYield 8%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
140 °C

Procedure

A mixture of 1-(2-bromoethyl)-4-nitrobenzene (18.7 g), pyrazole (5.53 g) and potassium hydroxide (4.56 g) was stirred at 140° C. for 8 min. The reaction mixture was poured into water, and the mixture was extracted with ethyl acetate. The organic layer was washed with water, dried over anhydrous magnesium sulfate, and concentrated. The residue was subjected to silica gel column chromatography to give 1-[2-(4-nitrophenyl)ethyl]-1H-pyrazole (1.37 g, 8%) as crystals from a fraction eluted with hexane-ethyl acetate (1:2, v/v). Recrystallization thereof from ethyl acetate-hexane gave yellow prism crystals. melting point: 92-93° C.

Workup

  1. extractionthe mixture was extracted with ethyl acetate
  2. washThe organic layer was washed with water
  3. dry with materialdried over anhydrous magnesium sulfate
  4. concentrationconcentrated

Sources & evidence

ORD record
ord-63a98340bebf4655b901d80ba0441790
Source dataset
uspto-grants-2008_09
Patent number
US07423159B2

Linked notes

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