Sodium Phosphate, Dibasic → 5-Amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-(2-trifluoromethylfuran-3-yl)pyrazole

HRID 1108831Notes

Reaction equation

HRID 1108831 reaction equation
[NH2:1][C:2]1[N:6]([C:7]2[C:12]([Cl:13])=[CH:11][C:10]([C:14]([F:17])([F:16])[F:15])=[CH:9][C:8]=2[Cl:18])[N:5]=[C:4]([C:19]#[N:20])[C:3]=1[C:21]1[CH:25]=[CH:24][O:23][CH:22]=1.S(S([O-])=O)([O-])=O.[Na+].[Na+].P([O-])([O-])(O)=O.[Na+].[Na+]>CN(C)C=O.O>[NH2:1][C:2]1[N:6]([C:7]2[C:8]([Cl:18])=[CH:9][C:10]([C:14]([F:17])([F:15])[F:16])=[CH:11][C:12]=2[Cl:13])[N:5]=[C:4]([C:19]#[N:20])[C:3]=1[C:21]1[CH:25]=[CH:24][O:23][C:22]=1[C:14]([F:17])([F:16])[F:15]

Participants

6

Reactant 3

HCID 24203Sodium Phosphate, DibasicHCID 24489Sodium DithioniteHCID 221209065-Amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-(3-furanyl)pyrazole

Product 1

HCID 221209015-Amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-(2-trifluoromethylfuran-3-yl)pyrazole

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6228DimethylformamideSolvent

Conditions

Temperature
50 °C

Procedure

To a solution of 5-amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-(furan-3-yl)pyrazole (0.5 g) in dimethylformamide (15 m) and water (5 ml) was added sodium dithionite (0.112 g) and disodium hydrogen phosphate (0.067 g). The mixture placed in a 400 ml Parr vessel, which was evacuated, then charged with trifluoromethylbromide gas to 20 psi. The mixture was shaken and heated at 50° C., for 2.5 hours, then left at room temperature for 16 hours. The vessel Mwas then evacuated, then charged with trifluoromethylbromide to 40 psi, then shaken and heated to 50° C. for a further 7 hours, then left at room temperature for 16 hours. Further sodium dithionite (0.120 g) and disodium hydrogen phosphate (0.080 g) was added, the vessel evacuated, then charged with trifluoromethylbromide to 40 psi, then shaken and heated to 50° C. as before for 9 hours, then left at room temperature for 48 hours. Further sodium dithionite (0.240 g) and disodium hydrogen phosphate (0.160 g) were added, the vessel was evacuated, then charged w-ith trifluoromethylbromide to 45 psi, then shaken and heated to 50° C. as before for a further 9 hours. The mixture was filtered and then poured into ether (100 ml) and water (100 ml). The organic layer was separated, washed twice with water (50 ml), dried (Na2SO4), and evaporated. The residue was purified by column chromatography on silica gel (25 g) eluted with dichloromethane. Combination and evaporation of suitable fractions gave 5-amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-(2-trifluoromethylfuran-3-yl)pyrazole as a white solid, m.p. 155-7° C.

Workup

  1. customwas evacuated
  2. additioncharged with trifluoromethylbromide gas to 20 psi
  3. customThe vessel Mwas then evacuated
  4. additioncharged with trifluoromethylbromide to 40 psi
  5. stirringshaken
  6. temperatureheated to 50° C. for a further 7 hours
  7. waitleft at room temperature for 16 hours
  8. additionFurther sodium dithionite (0.120 g) and disodium hydrogen phosphate (0.080 g) was added
  9. customthe vessel evacuated
  10. additioncharged with trifluoromethylbromide to 40 psi
  11. stirringshaken
  12. temperatureheated to 50° C. as before for 9 hours
  13. waitleft at room temperature for 48 hours
  14. additionFurther sodium dithionite (0.240 g) and disodium hydrogen phosphate (0.160 g) were added
  15. customthe vessel was evacuated
  16. additioncharged w-ith trifluoromethylbromide to 45 psi
  17. stirringshaken
  18. temperatureheated to 50° C. as before for a further 9 hours
  19. filtrationThe mixture was filtered
  20. additionpoured into ether (100 ml) and water (100 ml)
  21. customThe organic layer was separated
  22. washwashed twice with water (50 ml)
  23. dry with materialdried (Na2SO4)
  24. customevaporated
  25. customThe residue was purified by column chromatography on silica gel (25 g)
  26. washeluted with dichloromethane
  27. customCombination and evaporation of suitable fractions

Sources & evidence

ORD record
ord-2efb002d8aee48d0a0f08e6421642cfa
Source dataset
uspto-grants-2000_05
Patent number
US06069157

Reaction notes

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