Pyrazole → HCID 43381460, compound

HRID 1723866Notes

Reaction equation

HRID 1723866 reaction equation
N1C=CC=N1.[CH3:6][O:7][C:8]1[CH:18]=[CH:17][C:11]([C:12]([CH2:14][C:15]#[N:16])=O)=[CH:10][CH:9]=1.Cl.[C:20]([NH:24][NH2:25])([CH3:23])([CH3:22])[CH3:21]>>[C:20]([N:24]1[C:15]([NH2:16])=[CH:14][C:12]([C:11]2[CH:10]=[CH:9][C:8]([O:7][CH3:6])=[CH:18][CH:17]=2)=[N:25]1)([CH3:23])([CH3:22])[CH3:21]

Participants

4

Reactant 3

HCID 1048PyrazoleHCID 81889tert-Butylhydrazine monohydrochlorideHCID 2333984-Methoxybenzoylacetonitrile

Product 1

HCID 43381460HCID 43381460, compound

Procedure

General procedure for pyrazole formation: An ethanolic solution (3 mL) of 4-methoxybenzoylacetonitrile (500 mg, 2.85 mmol), t-butylhydrazine hydrochloride (391 mg, 3.14 mmol), and catalyticp-toluenesulfonic acid was stirred under argon at 90° C. for 4 h in a sealed tube. The reaction was concentrated and the residue partitioned between EtOAc and sat. NaHCO3. The organic layer was washed with brine, dried with Na2SO4, filtered and concentrated in vacuo. The residue was chromatographed on silica gel with a gradient of 10-30% EtOAc in Hexanes which yielded 2-tert-Butyl-5-(4-methoxyphenyl)-2H-pyrazol-3-ylamine: 1H NMR (400 MHz, CDCl3) δ 1.70 (s, 9H), 3.58 (br.s, 2H), 3.84 (s, 3H), 5.85 (s, 1H), 6.91 (d, J=8.8 Hz, 2H), 7.69 (d, J=8.8 Hz, 2H); MS (ES+): m/z 246 [MH+], m/z 190 [M-tbutyl].

Workup

  1. concentrationThe reaction was concentrated
  2. customthe residue partitioned between EtOAc and sat. NaHCO3
  3. washThe organic layer was washed with brine
  4. dry with materialdried with Na2SO4
  5. filtrationfiltered
  6. concentrationconcentrated in vacuo
  7. customThe residue was chromatographed on silica gel with a gradient of 10-30% EtOAc in Hexanes which

Sources & evidence

ORD record
ord-0af7dba21592418a85f1f79b7d788ffb
Source dataset
uspto-grants-2009_02
Patent number
US07485658B2

Reaction notes

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