Lawesson's reagent → ethyl 1-[(4-carbamothioyl-1,3-thiazol-2-yl)methyl]-1H-pyrazole-4-carboxylate

HRID 1257346Notes

Reaction equation

HRID 1257346 reaction equation
[C:1]([C:4]1[N:5]=[C:6]([CH2:9][N:10]2[CH:14]=[C:13]([C:15]([O:17][CH2:18][CH3:19])=[O:16])[CH:12]=[N:11]2)[S:7][CH:8]=1)(=O)[NH2:2].COC1C=CC(P2(=S)SP(=S)(C3C=CC(OC)=CC=3)[S:29]2)=CC=1.C(=O)([O-])O.[Na+]>C1(C)C=CC=CC=1>[C:1]([C:4]1[N:5]=[C:6]([CH2:9][N:10]2[CH:14]=[C:13]([C:15]([O:17][CH2:18][CH3:19])=[O:16])[CH:12]=[N:11]2)[S:7][CH:8]=1)(=[S:29])[NH2:2]

Participants

5

Reactant 3

HCID 87949Lawesson's reagentHCID 516892Sodium BicarbonateHCID 58127585ethyl 1-[(4-carbamoyl-1,3-thiazol-2-yl)methyl]-1H-pyrazole-4-carboxylate

Product 1

HCID 58127662ethyl 1-[(4-carbamothioyl-1,3-thiazol-2-yl)methyl]-1H-pyrazole-4-carboxylateYield 36.1%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

To a solution (10 mL) of the compound (524 mg, 1.87 mmol) obtained in Example 33b in toluene was added 2,4-bis(4-methoxyphenyl)-1,3-dithia-2,4-diphosphetane-2,4-disulfide (Lawesson reagent, 756 mg, 1.87 mmol), and the mixture was heated under reflux overnight. The reaction mixture was allowed to cool to room temperature, saturated aqueous sodium hydrogen carbonate solution was added, and the mixture was stirred for 30 min, and extracted with ethyl acetate. The obtained organic layer was washed with saturated brine, and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure. The obtained crude product was purified by column chromatography (hexane-hexane/ethyl acetate=1/1) and recrystallization (ethyl acetate-hexane) to give the title compound (200 mg, 36%) as pale-yellow crystals.

Workup

  1. temperaturethe mixture was heated
  2. temperatureunder reflux overnight
  3. extractionextracted with ethyl acetate
  4. washThe obtained organic layer was washed with saturated brine
  5. dry with materialdried over anhydrous sodium sulfate
  6. customThe solvent was evaporated under reduced pressure
  7. customThe obtained crude product
  8. customwas purified by column chromatography (hexane-hexane/ethyl acetate=1/1) and recrystallization (ethyl acetate-hexane)

Sources & evidence

ORD record
ord-0e8a2bc57c9b4a8bbf83aa089186877d
Source dataset
uspto-grants-2013_06
Patent number
US08461348B2

Reaction notes

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