[2-(5-Benzylamino-3-bromo-4-nitropyrazol-1-yl)ethyl]carbamic acid tert-butyl ester → Hydrogen Bromide

HRID 1744174Notes

Reaction equation

HRID 1744174 reaction equation
[C:1]([O:5][C:6](=[O:27])[NH:7][CH2:8][CH2:9][N:10]1[C:14]([NH:15][CH2:16][C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=2)=[C:13]([N+:23]([O-:25])=[O:24])[C:12]([Br:26])=[N:11]1)([CH3:4])([CH3:3])[CH3:2]>CCO.[Pd]>[C:1]([O:5][C:6](=[O:27])[NH:7][CH2:8][CH2:9][N:10]1[C:14]([NH:15][CH2:16][C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=2)=[C:13]([N+:23]([O-:25])=[O:24])[C:12]([Br:26])=[N:11]1)([CH3:4])([CH3:2])[CH3:3].[BrH:26]

Participants

5

Reactant 1

HCID 13007947[2-(5-Benzylamino-3-bromo-4-nitropyrazol-1-yl)ethyl]carbamic acid tert-butyl ester

Product 2

HCID 260Hydrogen BromideHCID 13007947[2-(5-Benzylamino-3-bromo-4-nitropyrazol-1-yl)ethyl]carbamic acid tert-butyl ester

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 702EthanolSolvent

Procedure

A mixture of [2-(5-benzylamino-3-bromo-4-nitropyrazol-1-yl)ethyl]carbamic acid tert-butyl ester (2.1 g; 4.76 mmol) in EtOH (100 ml) containing a 5% Pd/C catalyst (Engelhard type, 50% moisture, 0.4 g wet weight) was hydrogenated in an autoclave (250 ml) at 15 bar for 3 h. The catalyst was filtered off under an inert atmosphere and washed with EtOH, and the filtrate was recovered in an ethanolic solution (25 ml) containing hydrobromic acid (47%, 2 ml). The orange-colored solution was evaporated to dryness to give the 2-(2-aminoethyl)-2H-pyrazole-3,4-diamine in the hydrobromide form (3.55 HBr) as a pale pink solid (1.5 g, 92%).

Workup

  1. filtrationThe catalyst was filtered off under an inert atmosphere
  2. washwashed with EtOH
  3. customthe filtrate was recovered in an ethanolic solution (25 ml)
  4. additioncontaining hydrobromic acid (47%, 2 ml)
  5. customThe orange-colored solution was evaporated to dryness

Sources & evidence

ORD record
ord-de7d0c6c8bdf4353abfbfdc14eb20a86
Source dataset
uspto-grants-2006_03
Patent number
US07014663B2

Reaction notes

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