3-Bromophenylhydrazine hydrochloride → 1-(3-Bromophenyl)-3-tert-butyl-1H-pyrazol-5-amine

HRID 75606

Reaction equation

HRID 75606 reaction equation
Cl.[Br:2][C:3]1[CH:4]=[C:5]([NH:9][NH2:10])[CH:6]=[CH:7][CH:8]=1.[CH3:11][C:12]([CH3:19])([CH3:18])[C:13](=O)[CH2:14][C:15]#[N:16]>C(O)C>[Br:2][C:3]1[CH:4]=[C:5]([N:9]2[C:15]([NH2:16])=[CH:14][C:13]([C:12]([CH3:19])([CH3:18])[CH3:11])=[N:10]2)[CH:6]=[CH:7][CH:8]=1

Participants

4

Reactant 2

HCID 337573-Bromophenylhydrazine hydrochlorideHCID 108871Pentanenitrile, 4,4-dimethyl-3-oxo-

Product 1

HCID 184498781-(3-Bromophenyl)-3-tert-butyl-1H-pyrazol-5-amineYield 54%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A mixture of 3-bromophenylhydrazine hydrochloride (5.00 g, 22.4 mmol) and 4,4-dimethyl-3-oxo-pentanenitrile (4.29 g, 33.6 mmol) in absolute ethanol (55 mL) was stirred at reflux for 18 h and cooled, then concentrated in vacuo. The residue was suspended in sat. aq. NaHCO3 (50 mL) and extracted with EtOAc (3×50 mL). The combined organics were dried (Na2SO4) and concentrated in vacuo. The residue was purified by FCC, using 0-5% [2M NH3 in MeOH] in DCM, to give the title compound (3.56 g, 54%). LCMS (Method 1): Rt 3.33 min, m/z 294, 296 [MH+].

Workup

  1. temperatureat reflux for 18 h
  2. temperaturecooled
  3. concentrationconcentrated in vacuo
  4. extractionextracted with EtOAc (3×50 mL)
  5. dry with materialThe combined organics were dried (Na2SO4)
  6. concentrationconcentrated in vacuo
  7. customThe residue was purified by FCC

Sources & evidence

ORD record
ord-c70ba990100341a893ddcfbb212b4c89
Source dataset
uspto-grants-2014_09
Patent number
US08835431B2

Linked notes

Loading…