Acetic Anhydride → 5-Amino-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-(2,5-dimethylbenzoyl)-3-ethoxypyrazole

HRID 727397

Reaction equation

HRID 727397 reaction equation
[CH3:1][C:2]1[CH:12]=[CH:11][C:10]([CH3:13])=[CH:9][C:3]=1[C:4]([CH2:6][C:7]#[N:8])=[O:5].C(O[C:17]([O:24][CH2:25][CH3:26])(OCC)OCC)C.C(OC(=O)C)(=O)C.[Cl:34][C:35]1[CH:40]=[C:39]([C:41]([F:44])([F:43])[F:42])[CH:38]=[C:37]([Cl:45])[C:36]=1[NH:46][NH2:47].C(N(CC)CC)C>CCOC(C)=O.O>[NH2:8][C:7]1[N:46]([C:36]2[C:37]([Cl:45])=[CH:38][C:39]([C:41]([F:42])([F:43])[F:44])=[CH:40][C:35]=2[Cl:34])[N:47]=[C:17]([O:24][CH2:25][CH3:26])[C:6]=1[C:4](=[O:5])[C:3]1[CH:9]=[C:10]([CH3:13])[CH:11]=[CH:12][C:2]=1[CH3:1]

Participants

8

Reactant 5

HCID 7918Acetic AnhydrideHCID 8471TriethylamineHCID 66213Tetraethyl orthocarbonateHCID 688223[2,6-Dichloro-4-(trifluoromethyl)phenyl]hydrazineHCID 158952642,5-Dimethylbenzoylacetonitrile

Product 1

HCID 129721435-Amino-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-(2,5-dimethylbenzoyl)-3-ethoxypyrazole

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8857Ethyl AcetateSolvent

Procedure

A solution of 0.26 g (1.5 mmol) of 2,5-dimethylbenzoylacetonitrile, 0.34 mL (0.31 g, 1.60 mmol) of tetraethylorthocarbonate and 0.30 mL (0.33 g, 3.20 mmol) of acetic anhydride in 10 mL of EtOAc was refluxed overnight. The solvent was evaporated and 10 mL of absolute ethanol was added and then stripped. The residues were dissolved in 10 mL of ethanol, 368 mg (1.5 mmol) of 2,6-dichloro-4-trifluoromethylphenylhydrazine and 0.7 mL (0.51 g, 5.0 mmol) of triethylamine were added, and the mixture was refluxed for 90 minutes. The mixture was poured into water, extracted with EtOAc and the organic extracts were washed with dilute HCl and brine, and dried over MgSO4. Evaporation gave a gum which was chromatographed on silica gel with 4:1 hexane/EtOAc to give the title product which crystallized from pentane, 15 mg (2%), m.p. 99°-101° C.

Workup

  1. customThe solvent was evaporated
  2. addition10 mL of absolute ethanol was added
  3. dissolutionThe residues were dissolved in 10 mL of ethanol
  4. temperaturethe mixture was refluxed for 90 minutes
  5. extractionextracted with EtOAc
  6. washthe organic extracts were washed with dilute HCl and brine
  7. dry with materialdried over MgSO4
  8. customEvaporation
  9. customgave a gum which
  10. customwas chromatographed on silica gel with 4:1 hexane/EtOAc

Sources & evidence

ORD record
ord-89124b2ae7844187a54394383f88df9e
Source dataset
uspto-grants-1998_01
Patent number
US05712303

Linked notes

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