Diethyl Ether → 5-Amino-1-(2,6-dimethylphenyl)-1H-pyrazole-4-carbonitrile

HRID 2406111

Reaction equation

HRID 2406111 reaction equation
Cl.[CH3:2][C:3]1[CH:8]=[CH:7][CH:6]=[C:5]([CH3:9])[C:4]=1[NH:10][NH2:11].C(O[CH:15]=[C:16]([C:19]#[N:20])[C:17]#[N:18])C.C(N(CC)CC)C.C(OCC)C>C(O)C>[NH2:20][C:19]1[N:10]([C:4]2[C:5]([CH3:9])=[CH:6][CH:7]=[CH:8][C:3]=2[CH3:2])[N:11]=[CH:15][C:16]=1[C:17]#[N:18]

Participants

6

Reactant 4

HCID 3283Diethyl EtherHCID 8471TriethylamineHCID 671522-(Ethoxymethylene)propanedinitrileHCID 124050102,6-Dimethylphenylhydrazine hydrochloride

Product 1

HCID 121505545-Amino-1-(2,6-dimethylphenyl)-1H-pyrazole-4-carbonitrile

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

3.0 g (17.3 mmol) of 2,6-dimethylphenylhydrazine hydrochloride are suspended with 2.1 g (17.3 mmol) of ethoxymethylenemalononitrile in 40 ml of ethanol, and 7.3 ml (52.1 mmol) of triethylamine are added. The reaction mixture is heated to reflux for 3 h, during which a clear solution forms. After cooling to room temperature, diethyl ether is added to this. The triethylammonium chloride which precipitates is filtered off. The solvent is removed in vacuo, and the residue is purified by preparative HPLC (YMC gel ODS-AQ S 5/15 μm; eluent A: water, eluent B: acetonitrile; gradient: 0 min 30% B, 5 min 30% B, 50 min 95% B). 2.3 g (62% of theory) of the product are obtained as yellow crystals.

Workup

  1. additionare added
  2. temperatureThe reaction mixture is heated
  3. temperatureto reflux for 3 h, during which a clear solution forms
  4. customThe triethylammonium chloride which precipitates
  5. filtrationis filtered off
  6. customThe solvent is removed in vacuo
  7. customthe residue is purified by preparative HPLC (YMC gel ODS-AQ S 5/15 μm; eluent A: water, eluent B: acetonitrile; gradient: 0 min 30% B, 5 min 30% B, 50 min 95% B)
  8. custom2.3 g (62% of theory) of the product are obtained as yellow crystals

Sources & evidence

ORD record
ord-6eee0d69dcc648408a359c26045562e4
Source dataset
uspto-grants-2014_08
Patent number
US08809348B2

Linked notes

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