Benzyl Bromide → 1-benzyl-1H-pyrazol-3-amine

HRID 883047

Reaction equation

HRID 883047 reaction equation
[NH:1]1[CH:5]=[CH:4][C:3]([N:6]2C(=O)C3C(=CC=CC=3)C2=O)=[N:2]1.[H-].[Na+].[CH2:19](Br)[C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1>CN(C=O)C>[CH2:19]([N:1]1[CH:5]=[CH:4][C:3]([NH2:6])=[N:2]1)[C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1

Participants

5

Reactant 3

HCID 7498Benzyl BromideHCID 24758Sodium hydrideHCID 178514958HCID 178514958, compound

Product 1

HCID 15086161-benzyl-1H-pyrazol-3-amineYield 32%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Conditions

Temperature
50 °C

Procedure

3.1 2-(1H-Pyrazole-3-yl)-isoindole-1,3-dione (11.7 mmol) is added to a suspension of NaH (2 eq.) in DMF at 0° C. Benzylbromide (1 eq.) is added and the reaction is stirred 15 h at 50° C. The solvent is removed in vacuo. Hydrazine hydroxide (10 ml) and ethanol (20 ml) are added and the reaction is stirred 17 hours at 120° C. The precipitate is filtered and the solvent is removed in vacuo. The residue is suspended in dichloromethane and filtrated. The solvent of the filtrate is removed in vacuo. The remaining residue is purified via column chromatography (Ethyl acetate/methanol). 1-Benzyl-1H-pyrazole-3-ylamine is isolated as a yellow powder in a yield of 32%; HPLC (Method B): 2.45 min; LC-MS (Method B): 1.203 min, 174.15 (M+H+);

Workup

  1. customThe solvent is removed in vacuo
  2. additionHydrazine hydroxide (10 ml) and ethanol (20 ml) are added
  3. stirringthe reaction is stirred 17 hours at 120° C
  4. filtrationThe precipitate is filtered
  5. customthe solvent is removed in vacuo
  6. filtrationfiltrated
  7. customThe solvent of the filtrate is removed in vacuo
  8. customThe remaining residue is purified via column chromatography (Ethyl acetate/methanol)

Sources & evidence

ORD record
ord-d65f0c7dc5fa45feb0aaf321b69d9ab7
Source dataset
uspto-grants-2012_08
Patent number
US08236824B2

Linked notes

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