Sulfuric Acid → HCID 19025451, compound

HRID 1033181Notes

Reaction equation

HRID 1033181 reaction equation
[I-:1].[K+].N[C:4]1[CH:9]=[CH:8][C:7]([N:10]2[C:14](=[S:15])[N:13]([CH3:16])[N:12]=[C:11]2[C:17]([F:20])([F:19])[F:18])=[C:6]([Cl:21])[CH:5]=1.N([O-])=O.[Na+].S(=O)(=O)(O)O>O>[Cl:21][C:6]1[CH:5]=[C:4]([I:1])[CH:9]=[CH:8][C:7]=1[N:10]1[C:14](=[S:15])[N:13]([CH3:16])[N:12]=[C:11]1[C:17]([F:20])([F:19])[F:18]

Participants

6

Reactant 4

HCID 1118Sulfuric AcidHCID 4875Potassium IodideHCID 19025437HCID 19025437, compound2×HCID 23668193Sodium Nitrite

Product 1

HCID 19025451HCID 19025451, compoundYield 36.8%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

To a stirred, warm (40° C.) solution of 10.8 g (0.0648 mole) of potassium iodide in 80 ml of water was added dropwise a solution of 10.0 g (0.0324 mole) of 4-(4-amino-2-chlorophenyl)-3-trifluoromethyl-4,5-dihydro-1-methyl-1,2,4triazol-5(1H)-thione (Compound 94 to Table 1, prepared in Step C of Example 2), 2.70 g (0.389 mole) of sodium nitrite, and 20.0 g (0.204 mole) of concentrated sulfuric acid in 125 g of ice-cold water. The resultant mixture was stirred at 40° C. for three hours. The mixture was cooled and was extracted with methylene chloride. The extract was washed with an aqueous sodium metabisulfite solution. The washed organic phase was dried over anhydrous magnesium sulfate and was filtered. The filtrate was evaporated under reduced pressure, leaving a residue. This residue was purified by column chromatography on silica gel, eluting with petroleum ether:diethyl ether (75:25) to yield 5.0 g of 4-(2-chloro-4iodophenyl)-3-trifluoromethyl -4,5-dihydro-1-methyl-1,2,4-triazol-5(1H)-thione as a solid, mp 117°-119° C., Compound 91 of Table 1. The nmr spectra were consistent with the proposed structure.

Workup

  1. temperatureThe mixture was cooled
  2. extractionwas extracted with methylene chloride
  3. washThe extract was washed with an aqueous sodium metabisulfite solution
  4. dry with materialThe washed organic phase was dried over anhydrous magnesium sulfate
  5. filtrationwas filtered
  6. customThe filtrate was evaporated under reduced pressure
  7. customleaving a residue
  8. customThis residue was purified by column chromatography on silica gel
  9. washeluting with petroleum ether:diethyl ether (75:25)

Sources & evidence

ORD record
ord-2cfe9929edd84738bc708582f4af6031
Source dataset
uspto-grants-1994_05
Patent number
US05310724

Reaction notes

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