Chloroform → 1-(4-Hydroxymethylphenyl)-3-methyl-2-pyrazolin-5-one

HRID 1290560Notes

Reaction equation

HRID 1290560 reaction equation
C(Cl)(Cl)Cl.[CH3:5][C:6]1[CH2:10][C:9](=[O:11])[N:8]([C:12]2[CH:20]=[CH:19][C:15]([C:16](O)=[O:17])=[CH:14][CH:13]=2)[N:7]=1.C(Cl)(=O)OCC>C(N(CC)CC)C>[OH:17][CH2:16][C:15]1[CH:14]=[CH:13][C:12]([N:8]2[C:9](=[O:11])[CH2:10][C:6]([CH3:5])=[N:7]2)=[CH:20][CH:19]=1

Participants

5

Reactant 3

HCID 6212ChloroformHCID 10928Ethyl chloroformateHCID 1090294-(3-Methyl-5-oxo-2-pyrazolin-1-yl)benzoic acid

Product 1

HCID 103079441-(4-Hydroxymethylphenyl)-3-methyl-2-pyrazolin-5-oneYield 35%

Reagents, catalysts & solvents 1

HCID 8471TriethylamineSolvent

Procedure

Into 250 ml of anhydrous chloroform were added 5.0 g of 4-(3-methyl-5-oxo-2-pyrazolin-1-yl)benzoic acid and 25 ml of triethylamine and, further under ice-cooling, 12.5 ml of ethyl chlorocarbonate was added dropwise into the mixture. After evaporation of the solvent, the residue was dissolved in 200 ml of THF, the insolubles were filtered off, and then a solution of 2.08 g of NaBH4 dissolved in 60 ml of water was added dropwise into the filtrate, followed by stirring at room temperature for 2 hours. After evaporation of the solvent, water was added to the residue, and the mixture was adjusted with dil. hydrochloric acid to pH 4-5 and then extracted with chloroform. The organic layer was dried, concentrated and purified on silica gel column chromatograph with the use of chloroform-ethanl (100:1) as eluant, followed by recrystallization from chloroformethyl ether to give 1.16 g of 1-(4-hydroxymethylphenyl)-3-methyl-2-pyrazolin-5-one as colorless crystals.

Workup

  1. temperaturefurther under ice-cooling
  2. customAfter evaporation of the solvent
  3. dissolutionthe residue was dissolved in 200 ml of THF
  4. filtrationthe insolubles were filtered off
  5. dissolutiona solution of 2.08 g of NaBH4 dissolved in 60 ml of water
  6. additionwas added dropwise into the filtrate
  7. customAfter evaporation of the solvent, water
  8. additionwas added to the residue
  9. extractionextracted with chloroform
  10. customThe organic layer was dried
  11. concentrationconcentrated
  12. custompurified on silica gel column chromatograph with the use of chloroform-ethanl (100:1) as eluant
  13. customfollowed by recrystallization from chloroformethyl ether

Sources & evidence

ORD record
ord-73d2c9d0ddd04630aa10a63130d4e159
Source dataset
uspto-grants-1998_05
Patent number
USRE035801

Reaction notes

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