Thiourea → 79382-71-1

HRID 1902881Notes

Reaction equation

HRID 1902881 reaction equation
[CH3:1][C:2]1[CH:6]=[CH:5][N:4]([C:7]2[CH:12]=[CH:11][C:10]([C:13](Cl)=[O:14])=[CH:9][CH:8]=2)[N:3]=1.[H][H].NC(N)=S>C1(C)C(C)=CC=CC=1.[Pd].[O-]S([O-])(=O)=O.[Ba+2]>[CH3:1][C:2]1[CH:6]=[CH:5][N:4]([C:7]2[CH:12]=[CH:11][C:10]([CH:13]=[O:14])=[CH:9][CH:8]=2)[N:3]=1

Participants

6

Reactant 3

HCID 2723790ThioureaHCID 22605448HCID 22605448, compoundHCID 178418361HCID 178418361, compound

Product 1

HCID 2051410079382-71-1Yield 92%

Reagents, catalysts & solvents 2

HCID 16218511Pd barium sulfateCatalystHCID 7237O-XyleneSolvent

Conditions

Temperature
80 °C

Procedure

Using the method of Rosenmund, 88 g of the above 3-methyl-1-(4-chloroformylphenyl)pyrazole are hydrogenated with hydrogen at 140° C. in 900 ml of xylene with the addition of 0.23 g of thiourea and 9 g of Pd/BaSO4 (5%). After cooling to 80° C. and removing the catalyst by filtration, the xylene solution is evaporated to dryness and the precipitated product is recrystallised from a mixture of hexane and toluene, affording 68.3 g of 3-methyl-1-(4-formylphenyl)pyrazole in the form of pale yellow crystals with a melting point of 96°-98° C.

Workup

  1. customremoving the catalyst
  2. filtrationby filtration
  3. customthe xylene solution is evaporated to dryness
  4. customthe precipitated product is recrystallised from a mixture of hexane and toluene

Sources & evidence

ORD record
ord-21a605f30a4340f9ac905c4f5f2c5dc2
Source dataset
uspto-grants-1982_12
Patent number
US04366189

Reaction notes

Loading…