Benzylhydrazine dihydrochloride → 1-benzyl-3-methyl-4-nitroso-5-phenyl-1H-pyrazole

HRID 719289Notes

Reaction equation

HRID 719289 reaction equation
[C:1]1([C:7](=O)[C:8](=[N:12][OH:13])[C:9](=O)[CH3:10])[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.Cl.Cl.[CH2:17]([NH:24][NH2:25])[C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1>CCO>[CH2:17]([N:24]1[C:7]([C:1]2[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=2)=[C:8]([N:12]=[O:13])[C:9]([CH3:10])=[N:25]1)[C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1

Participants

4

Reactant 2

HCID 146540Benzylhydrazine dihydrochlorideHCID 1784683762-hydroxyimino-1-phenylbutane-1,3-dione

Product 1

HCID 218979641-benzyl-3-methyl-4-nitroso-5-phenyl-1H-pyrazole

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent2×

Procedure

To a 0° C. solution of 2.32 g of 1-phenyl-butane-1,2,3-trione 2-oxime in 31 mL of EtOH was added a suspension of 2.43 g benzyl hydrazine dihydrochloride in 9 mL EtOH. The reaction mixture was warmed to rt and stirred for 96 h. The reaction mixture was concentrated under reduced pressure and purified by means of MPLC (120 g SiO2, 45% EtOAc:Heptane) to obtain 1-benzyl-3-methyl-4-nitroso-5-phenyl-1H-pyrazole. A suspension of 2.55 g 1-benzyl-3-methyl-4-nitroso-5-phenyl-1H-pyrazole, 34 mL EtOAc and 500 mg 10% Pd/C was reacted under 40 psi H2 atmosphere using a Parr apparatus. After 4 h, the suspension was filtered through Celite (EtOH eluting) and the filtrate was concentrated under reduced pressure and purified by means of MPLC (120 g SiO2, 60% EtOAc:Heptane) to give the title compound as an orange oil.

Workup

  1. concentrationThe reaction mixture was concentrated under reduced pressure
  2. custompurified by means of MPLC (120 g SiO2, 45% EtOAc:Heptane)

Sources & evidence

ORD record
ord-2553caa6becb4589836ecea78344c9d1
Source dataset
uspto-grants-2006_11
Patent number
US07132428B2

Reaction notes

Loading…