Carbon tetrabromide → 4-bromoethyl-5-(3,5-dichloro-phenylsulfanyl)-1-ethyl-3-methyl-1 H-pyrazole

HRID 350889Notes

Reaction equation

HRID 350889 reaction equation
[Cl:1][C:2]1[CH:3]=[C:4]([S:9][C:10]2[N:14]([CH2:15][CH3:16])[N:13]=[C:12]([CH3:17])[C:11]=2[CH2:18]O)[CH:5]=[C:6]([Cl:8])[CH:7]=1.[C:20](Br)(Br)(Br)[Br:21].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>ClCCl>[Br:21][CH2:20][CH2:18][C:11]1[C:12]([CH3:17])=[N:13][N:14]([CH2:15][CH3:16])[C:10]=1[S:9][C:4]1[CH:3]=[C:2]([Cl:1])[CH:7]=[C:6]([Cl:8])[CH:5]=1

Participants

5

Reactant 3

HCID 11205Carbon tetrabromideHCID 11776TriphenylphosphineHCID 227475205-(3,5-dichloro-phenylsulphanyl)-1-ethyl-3-methyl-1H-pyrazol-4-yl-methanol

Product 1

HCID 695157944-bromoethyl-5-(3,5-dichloro-phenylsulfanyl)-1-ethyl-3-methyl-1 H-pyrazoleYield 68.6%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

A mixture of 460 mg of [5-(3,5-dichloro-phenylsulphanyl)-1-ethyl-3-methyl-1H-pyrazol-4-yl-]methanol, 481 mg of carbon tetrabromide and 380 mg of triphenylphosphine in 20 ml of dichloromethane was stirred at room temperature for 24 hours. The solvent was evaporated. The residue was purified by flash chromatography on silica gel using ethyl acetate/petroleum ether (bp 40–60° C.) (1:4) for the elution to give 392 mg of 4-bromoethyl-5-(3,5-dichloro-phenylsulfanyl)-1-ethyl-3-methyl-1H-pyrazole as a pale yellow oil. Mass spectrum (ES) m/z 317 [M−Br+H2O]+.

Workup

  1. customThe solvent was evaporated
  2. customThe residue was purified by flash chromatography on silica gel
  3. washfor the elution

Sources & evidence

ORD record
ord-ea279b84e73944f585a96bd5f54c7172
Source dataset
uspto-grants-2007_02
Patent number
US07183296B2

Reaction notes

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