Sodium Hydroxide → 3-Hydrazino-1-methyl-5-methylmercaptopyrazole

HRID 1977084Notes

Reaction equation

HRID 1977084 reaction equation
[N:1]([O-])=O.[Na+].[NH2:5][C:6]1[CH:10]=[C:9]([S:11][CH3:12])[N:8]([CH3:13])[N:7]=1.O.[Sn](Cl)Cl.[OH-].[Na+]>O.Cl>[NH:5]([C:6]1[CH:10]=[C:9]([S:11][CH3:12])[N:8]([CH3:13])[N:7]=1)[NH2:1]

Participants

7

Reactant 4

HCID 14798Sodium HydroxideHCID 23668193Sodium NitriteHCID 43835034Tin dichloride dihydrateHCID 542284381-Methyl-5-(methylthio)-1H-pyrazol-3-amine

Product 1

HCID 451213143-Hydrazino-1-methyl-5-methylmercaptopyrazoleYield 96.5%

Reagents, catalysts & solvents 2

HCID 313Hydrochloric AcidSolvent2×HCID 962WaterSolvent

Conditions

Temperature
0 °C

Procedure

At 0° C., 1.1 g (15.8 mmol) of sodium nitrite in 4 ml of water are added dropwise to 1.9 g (13.1 mmol) of 3-amino-1-methyl-5-methylmercaptopyrazole in 18 ml of concentrated hydrochloric acid, and the mixture is stirred at 0° C. for 2 hours. At −30° C., a solution of 7.4 ml (32.8 mmol) of tin dichloride hydrate in 5.5 ml of conc. hydrochloric acid is added dropwise, and the mixture is stirred at this temperature for 3 hours. The mixture is then made alkaline using 32% strength aqueous sodium hydroxide solution and extracted with methylene chloride. The organic phase is dried (sodium sulfate) and the solvent is stripped off, giving 2.0 g of product which can be used without any further purification.

Workup

  1. stirringthe mixture is stirred at this temperature for 3 hours
  2. extractionextracted with methylene chloride
  3. dry with materialThe organic phase is dried (sodium sulfate)

Sources & evidence

ORD record
ord-2dd16a128689494ead372ac946fd78a9
Source dataset
uspto-grants-2001_05
Patent number
US06232271B1

Reaction notes

Loading…