Acetic Acid → 3-Methyl-1-phenyl-4,5-dihydro-1H-1,2,4-triazol-5-one

HRID 2399543Notes

Reaction equation

HRID 2399543 reaction equation
C1(NN)C=CC=CC=1.[C:9]1([NH:15][N:16]=[C:17](OC)[CH3:18])[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=1.[O-:21][C:22]#[N:23].[Na+].C(O)(=O)C>CO.O>[CH3:18][C:17]1[NH:23][C:22](=[O:21])[N:15]([C:9]2[CH:10]=[CH:11][CH:12]=[CH:13][CH:14]=2)[N:16]=1

Participants

7

Reactant 4

HCID 176Acetic AcidHCID 7516PhenylhydrazineHCID 517096Sodium CyanateHCID 54154372N-phenyl-N'-(1-methoxyethylidene)hydrazine

Product 1

HCID 1355376213-Methyl-1-phenyl-4,5-dihydro-1H-1,2,4-triazol-5-one

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 962WaterSolvent

Procedure

A stirred solution of 2.0 grams (0.019 mole) of phenylhydrazine and 2.7 grams (0.022 mole-1.2 eq.) of TMOA in 20 mL of methanol is heated at reflux for about 1.5 hours, until the reaction to the intermediate N-phenyl-N'-(1-methoxyethylidene)hydrazine is complete. The progress of the reaction is monitored by gas chromatography (GC). After this time, the reaction mixture is cooled in an ice-water bath (0° C.) and 1.5 grams (0.022 mole-1.2 eq.) of sodium cyanate is added. Upon completion of addition, 1.3 grams (0.022 mole-1.2 eq.) of acetic acid is added dropwise. The reaction mixture is then stirred at the ice-water bath temperature for about 10 minutes, then it is allowed to warm to ambient temperature. After this time, two mL of water is added to the reaction mixture. Upon completion of addition, the reaction mixture is stirred at ambient temperature for about ten hours. The reaction mixture is concentrated under reduced pressure, yielding 4,5-dihydro-3-methyl-1-phenyl-1,2,4-triazol-5(1 H)-one.

Workup

  1. additionis added
  2. additionis added dropwise
  3. additionUpon completion of addition
  4. concentrationThe reaction mixture is concentrated under reduced pressure

Sources & evidence

ORD record
ord-3672ed30bee94f34acb0593fcd3f1380
Source dataset
uspto-grants-1995_09
Patent number
US05449784

Reaction notes

Loading…