Triethylborane → 4-[1-Ethyl-4-(4-fluoro-phenyl)-5-trifluoromethyl-1H-pyrazol-3-yl]-benzenesulfonamide

HRID 375664Notes

Reaction equation

HRID 375664 reaction equation
[CH2:1]([N:3]1[C:7]([C:8]([F:11])([F:10])[F:9])=[C:6]([C:12]2[CH:17]=[CH:16][C:15]([F:18])=[CH:14][CH:13]=2)[C:5]([C:19]2[CH:24]=[CH:23][C:22]([S:25](C)(=[O:27])=[O:26])=[CH:21][CH:20]=2)=[N:4]1)[CH3:2].C([Mg]Cl)CCC.C(B(CC)CC)C.C([O-])(=O)C.[Na+].[NH2:47]OS(O)(=O)=O>C1COCC1.O>[CH2:1]([N:3]1[C:7]([C:8]([F:11])([F:10])[F:9])=[C:6]([C:12]2[CH:17]=[CH:16][C:15]([F:18])=[CH:14][CH:13]=2)[C:5]([C:19]2[CH:24]=[CH:23][C:22]([S:25]([NH2:47])(=[O:27])=[O:26])=[CH:21][CH:20]=2)=[N:4]1)[CH3:2]

Participants

8

Reactant 5

HCID 7357TriethylboraneHCID 76284hydroxylamine-O-sulfonic acidHCID 517045Sodium AcetateHCID 98445471-Ethyl-4-(4-fluoro-phenyl)-3-(4-methanesulfonyl-phenyl)-5-trifluoromethyl-1H-pyrazoleHCID 178418265HCID 178418265, compound

Product 1

HCID 102234614-[1-Ethyl-4-(4-fluoro-phenyl)-5-trifluoromethyl-1H-pyrazol-3-yl]-benzenesulfonamideYield 62%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8028TetrahydrofuranSolvent3×

Conditions

Temperature
25 °C

Procedure

1-Ethyl-4-(4-fluorophenyl)-3-[4-(methylsulfonyl)phenyl]-5-(trifluoromethyl)-1H-pyrazole (0.45 g, 1.0 mmol) was dissolved in 5 mL dry THF under nitrogen and treated with 0.9 mL of a 1.0M solution of n-butyl magnesium chloride in THF at 0° C. for 10 minutes and warmed to 25° C. for 30 minutes. A solution of triethylborane in THF (2.5 mL, 1.0M) was added and the mixture was stirred at 25° C. for 2 hours and at reflux for 24 hours. After cooling to 25° C., a mixture of water (1.2 mL), sodium acetate (0.90 g) and hydroxylamine-O-sulfonic acid (0.62 g) was added and the reaction stirred at 25° C. for 18 hours. The mixture was partitioned between water and ethyl acetate, and the organic layer washed successively with water and brine, dried over MgSO4 and concentrated in vacuo. Chromatographic purification on silica gel eluting with methyl t-butyl ether/toluene (5/95) gave 4-[1-ethyl-4-(4-fluorophenyl)-5-(trifluoromethyl)-1H-pyrazol-3-yl]benzenesulfonamide as a white solid (0.25 g, 62% yield). Elemental analysis for C18H15N3F4SO2Calc'd: C, 52.30, H, 3.66, N, 10.16, S, 7.76. Found: C, 52.36, H, 3.72, N, 9.98, S, 7.90.

Workup

  1. temperatureat reflux for 24 hours
  2. temperatureAfter cooling to 25° C.
  3. additionwas added
  4. stirringthe reaction stirred at 25° C. for 18 hours
  5. customThe mixture was partitioned between water and ethyl acetate
  6. washthe organic layer washed successively with water and brine
  7. dry with materialdried over MgSO4
  8. concentrationconcentrated in vacuo
  9. customChromatographic purification on silica gel eluting with methyl t-butyl ether/toluene (5/95)

Sources & evidence

ORD record
ord-7c4e48c4af214b9fb61df2111926934a
Source dataset
uspto-grants-1996_01
Patent number
US05486534

Reaction notes

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