Phenylhydrazine hydrochloride → 3-(1-Methylethyl)-1-phenyl-1H-pyrazol-5-amine

HRID 631671Notes

Reaction equation

HRID 631671 reaction equation
[CH3:1][CH:2]([CH3:8])[C:3](=O)[CH2:4][C:5]#[N:6].Cl.[C:10]1([NH:16][NH2:17])[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1>CCO>[CH:2]([C:3]1[CH:4]=[C:5]([NH2:6])[N:16]([C:10]2[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=2)[N:17]=1)([CH3:8])[CH3:1]

Participants

4

Reactant 2

HCID 60962Phenylhydrazine hydrochlorideHCID 101299214-Methyl-3-oxopentanenitrile

Product 1

HCID 27595063-(1-Methylethyl)-1-phenyl-1H-pyrazol-5-amineYield 77.8%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Conditions

Temperature
65 °C

Procedure

Using the procedure described in Example 308A Step 1, to a solution of 4-methyl-3-oxopentanenitrile (303 mg, 2.7 mmol) prepared as described in Example 122A Step 1, in anhydrous EtOH (6 ml) was added phenylhydrazine hydrochloride (473 mg, 3.3 mmol) and the reaction mixture was heated at 65° C. overnight. The residue was purified by silica gel chromatography (hexane/ethyl acetate 2-50%) to afford 3-isopropyl-1-phenyl-1H-pyrazol-5-amine (423 mg, 77%) as a solid. 1H NMR (300 MHz, CDCl3) δ 1.22 (d, J=6 Hz, 6H), 3.86 (brs, 2H), 5.35 (s, 1H), 7.21-7.49 (m, 5H); LC-MS (ESI) m/z 202 (M+H)+.

Workup

  1. customprepared
  2. customThe residue was purified by silica gel chromatography (hexane/ethyl acetate 2-50%)

Sources & evidence

ORD record
ord-5722ec518be944faa81a0fe855110c4e
Source dataset
uspto-grants-2016_04
Patent number
US09320739B2

Reaction notes

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