Triethylamine → 2-(4-trifluoromethylphenyl)-3(2H,4H)-1,2,4-triazolone

HRID 129164Notes

Reaction equation

HRID 129164 reaction equation
[F:1][C:2]([F:16])([F:15])[C:3]1[CH:8]=[CH:7][C:6]([NH:9][N:10]=[CH:11]C(O)=O)=[CH:5][CH:4]=1.C([N:19]([CH2:22]C)CC)C.C1(P(N=[N+]=[N-])(C2C=CC=CC=2)=[O:31])C=CC=CC=1>C1(C)C=CC=CC=1>[F:16][C:2]([F:1])([F:15])[C:3]1[CH:4]=[CH:5][C:6]([N:9]2[C:22](=[O:31])[NH:19][CH:11]=[N:10]2)=[CH:7][CH:8]=1

Participants

5

Reactant 3

HCID 8471TriethylamineHCID 199401P,P-Diphenylphosphinic azideHCID 69587423{2-[4-(Trifluoromethyl)phenyl]hydrazinylidene}acetic acid

Product 1

HCID 1355070392-(4-trifluoromethylphenyl)-3(2H,4H)-1,2,4-triazoloneYield 72.4%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Conditions

Temperature
120 °C

Procedure

4-(trifluoromethyl)phenylhydrazonoacetic acid (6.26 g, 27 mmol) was suspended in 176 ml of toluene, and 4.0 ml of triethylamine (28.7 mmol) and 6.1 ml of diphenylphosphorylazide (28.3 mmol) were added and the resulting mixture was stirred for one hour at 120° C. After cooling, the reaction solution was extracted with 200 ml of an aqueous solution of pottasium hydroxide (10%). The aqueous extract was acidified with concentrated hydrochloric acid to adjust pH to 1, and the crystals thus separated out were washed with water and hexane successively and dried over phosphorus pentoxide to give 4.48 g of 2-(4-trifluoromethylphenyl)-3(2H,4H)-1,2,4-triazolone (72%) as a colorless powder.

Workup

  1. temperatureAfter cooling
  2. extractionthe reaction solution was extracted with 200 ml of an aqueous solution of pottasium hydroxide (10%)
  3. extractionThe aqueous extract
  4. customthe crystals thus separated out
  5. washwere washed with water and hexane successively
  6. dry with materialdried over phosphorus pentoxide

Sources & evidence

ORD record
ord-aa5cc56ce697452f8e57ae325504ac0f
Source dataset
uspto-grants-1995_11
Patent number
US05466820

Reaction notes

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