Bromoform → 5-Bromo-1-(2,6-dichloro-4-trifluoromethylphenyl)-3-cyano-4-trifluoromethylsulfonylpyrazole

HRID 842136Notes

Reaction equation

HRID 842136 reaction equation
N[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[S:21]([C:24]([F:27])([F:26])[F:25])(=[O:23])=[O:22].C(#N)C.N(OC(C)(C)C)=O.C(Br)(Br)[Br:39]>>[Br:39][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[S:21]([C:24]([F:27])([F:26])[F:25])(=[O:23])=[O:22]

Participants

5

Reactant 4

HCID 5558BromoformHCID 6342AcetonitrileHCID 10906Tert-Butyl nitrite2×HCID 3078139Fipronil sulfone

Product 1

HCID 167270545-Bromo-1-(2,6-dichloro-4-trifluoromethylphenyl)-3-cyano-4-trifluoromethylsulfonylpyrazole

Conditions

Temperature
65 °C

Procedure

A suspension of 5-amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-trifluoromethanesulphonylpyrazole (43.8 g) was stirred in a mixture of bromoform (141 ml) and dry acetonitrile (63 ml). Tert-butyl nitrite (29.9 g) was added dropwise during 5 minutes, and the mixture heated at 60-70° C. for 2.75 hours. After cooling to 25° C. a further addition of tert-butyl nitrite (29.9 g) was made, and the heating resumed for 2 hours. Evaporation in vacuo gave a yellow oily solid which was triturated with hexane and filtered off. Two recrystallisations from toluene/hexane gave 5-bromo-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)4-trifluoromethanesulphonylpyrazole as a yellow solid (34.0 g), m.p. 136-137° C.

Workup

  1. temperatureAfter cooling to 25° C.
  2. customEvaporation in vacuo
  3. customgave a yellow oily solid which
  4. customwas triturated with hexane
  5. filtrationfiltered off
  6. customTwo recrystallisations from toluene/hexane

Sources & evidence

ORD record
ord-ae6cfa15f58d4afc80b4d53d1b5b7243
Source dataset
uspto-grants-2002_04
Patent number
US06372774B1

Reaction notes

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