Hydrochloric Acid → 1-(5-chloro-2-methylphenyl)-3-methyl-1H-pyrazol-5-amine

HRID 474335Notes

Reaction equation

HRID 474335 reaction equation
Cl.[Cl:2][C:3]1[CH:4]=[CH:5][C:6]([CH3:11])=[C:7]([NH:9][NH2:10])[CH:8]=1.Cl.[CH3:13]/[C:14](/N)=[CH:15]\[C:16]#[N:17].C(=O)(O)[O-].[Na+]>C(O)C>[Cl:2][C:3]1[CH:4]=[CH:5][C:6]([CH3:11])=[C:7]([N:9]2[C:16]([NH2:17])=[CH:15][C:14]([CH3:13])=[N:10]2)[CH:8]=1

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 516892Sodium BicarbonateHCID 53247203-AminocrotonitrileHCID 13200574(5-Chloro-2-methylphenyl)hydrazine hydrochloride

Product 1

HCID 580631601-(5-chloro-2-methylphenyl)-3-methyl-1H-pyrazol-5-amineYield 82.4%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Conditions

Temperature
80 °C

Procedure

To a solution of (5-chloro-2-methylphenyl)hydrazine hydrochloride (1.49 g, 7.72 mmol, 1.00 equiv) in ethanol (8 mL) was added hydrogen chloride (4.0 mL, 20 mmol, 2 equiv, 5 M aqueous solution) and 3-aminocrotonitrile (0.664 g, 8.09 mmol, 1.05 equiv). The reaction mixture was stirred at 80° C. for 16 hours and then brought to neutral pH with saturated aqueous sodium bicarbonate solution. The resultant solution was extracted twice with dichloromethane, and the combined extracts were dried over magnesium sulfate, filtered, and concentrated to yield 1.41 g (82%) of 1-(5-chloro-2-methylphenyl)-3-methyl-1H-pyrazol-5-amine, which was carried forward without further purification. LCMS (ESI) m+H=222.2; 1H NMR (400 MHz, DMSO-d6) δ: 7.39 (d, 1H), 7.37 (d, 1H), 7.25 (s, 1H), 5.22 (s, 1H), 5.00 (s, 2H), 2.04 (overlapping s and s, 6H).

Workup

  1. extractionThe resultant solution was extracted twice with dichloromethane
  2. dry with materialthe combined extracts were dried over magnesium sulfate
  3. filtrationfiltered
  4. concentrationconcentrated

Sources & evidence

ORD record
ord-47705f5147194256a31155996443c57b
Source dataset
uspto-grants-2014_01
Patent number
US08637526B2

Reaction notes

Loading…