Hydrochloric Acid → 3-Amino-1-(propan-2-yl)-1H-pyrazole-4-carbonitrile

HRID 1889234Notes

Reaction equation

HRID 1889234 reaction equation
C(=[N:8][N:9]([CH:13]=[C:14]([C:17]#[N:18])[C:15]#[N:16])[CH:10]([CH3:12])[CH3:11])C1C=CC=CC=1.Cl>C(O)C>[NH2:18][C:17]1[C:14]([C:15]#[N:16])=[CH:13][N:9]([CH:10]([CH3:11])[CH3:12])[N:8]=1

Participants

4

Reactant 2

HCID 313Hydrochloric AcidHCID 276227HCID 276227, compound

Product 1

HCID 2762283-Amino-1-(propan-2-yl)-1H-pyrazole-4-carbonitrile

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A mixture of Intermediate 2-((2-benzylidene-1-isopropylhydrazinyl)-methylene)malononitrile (9.42 g, 40 mmol), concentrated hydrochloric acid (5 ml), and ethanol (50 ml) was heated at reflux for 20 min. The reaction mixture was concentrated and ether (50 ml) was added. The mixture was sonicated, then the upper ether layer was discarded. To the residue was added 20 ml of 5N aqueous sodium hydroxide solution and the mixture was extracted with dichloromethane (3×). The organic layers were combined, dried over sodium sulfate, filtered, and concentrated. The residue was purified by silica gel column chromatography (1:1 hexanes/ethyl acetate eluant) to afford 3-amino-1-isopropyl-1H-pyrazole-4-carbonitrile as a brown solid. 1H NMR (400 MHz, DMSO-d6) δ 8.09 (s, 1H), 5.51 (s, 2H), 4.22 (m, 1H), 1.31 (d, J=7 Hz, 6H); MS m/z 151.2 (M+1).

Workup

  1. temperaturewas heated
  2. temperatureat reflux for 20 min
  3. concentrationThe reaction mixture was concentrated
  4. additionether (50 ml) was added
  5. customThe mixture was sonicated
  6. additionTo the residue was added 20 ml of 5N aqueous sodium hydroxide solution
  7. extractionthe mixture was extracted with dichloromethane (3×)
  8. dry with materialdried over sodium sulfate
  9. filtrationfiltered
  10. concentrationconcentrated
  11. customThe residue was purified by silica gel column chromatography (1:1 hexanes/ethyl acetate eluant)

Sources & evidence

ORD record
ord-bdb24e21494f44cb9d20ed73bff7fd55
Source dataset
uspto-grants-2013_08
Patent number
US08501758B2

Reaction notes

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