Ethyl 4,5-dichloro-6-(1-methyl-5-pyrazolylcarbonyl)-1,3-benzodioxole-2-carboxylate → Ethyl 4,5-dichloro-6-(1-methyl-4-bromo-5-pyrazolylcarbonyl)-1,3-benzodioxole-2-carboxylate

HRID 1074179Notes

Reaction equation

HRID 1074179 reaction equation
O.O.O.[Br:4]([O-])(=O)=O.[Na+].[Cl:9][C:10]1[C:18]2[O:17][CH:16]([C:19]([O:21][CH2:22][CH3:23])=[O:20])[O:15][C:14]=2[CH:13]=[C:12]([C:24]([C:26]2[N:30]([CH3:31])[N:29]=[CH:28][CH:27]=2)=[O:25])[C:11]=1[Cl:32]>O.C(O)(=O)C>[Cl:9][C:10]1[C:18]2[O:17][CH:16]([C:19]([O:21][CH2:22][CH3:23])=[O:20])[O:15][C:14]=2[CH:13]=[C:12]([C:24]([C:26]2[N:30]([CH3:31])[N:29]=[CH:28][C:27]=2[Br:4])=[O:25])[C:11]=1[Cl:32]

Participants

5

Reactant 2

HCID 14748603Ethyl 4,5-dichloro-6-(1-methyl-5-pyrazolylcarbonyl)-1,3-benzodioxole-2-carboxylateHCID 23713285Sodium bromate trihydrate

Product 1

HCID 15052559Ethyl 4,5-dichloro-6-(1-methyl-4-bromo-5-pyrazolylcarbonyl)-1,3-benzodioxole-2-carboxylateYield 41.2%

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolventHCID 962WaterSolvent

Procedure

A solution of 1.53 g of sodium bromate trihydrate in 5 ml of water is added to a solution of 2.0 g of ethyl 4,5-dichloro-6-(1-methyl-5-pyrazolylcarbonyl)-1,3-benzodioxole-2-carboxylate in 20 ml of acetic acid at room temperature. The mixture is stirred at the same temperature for 15 hours. The reaction mixture is concentrated under reduced pressure to remove acetic acid. The residue is neutralized by addition of an aqueous saturated sodium bicarbonate solution and extracted with ethyl acetate. The extract is washed with water, dried and evaporated to remove solvent. The residue is purified by silica gel column chromatography (solvent; n-hexane-ethyl acetate) to give 1.0 g of ethyl 4,5-dichloro-6-(1-methyl-4-bromo-5-pyrazolylcarbonyl)-1,3-benzodioxole-2-carboxylate as an oil.

Workup

  1. concentrationThe reaction mixture is concentrated under reduced pressure
  2. customto remove acetic acid
  3. additionThe residue is neutralized by addition of an aqueous saturated sodium bicarbonate solution
  4. extractionextracted with ethyl acetate
  5. washThe extract is washed with water
  6. customdried
  7. customevaporated
  8. customto remove solvent
  9. customThe residue is purified by silica gel column chromatography (solvent; n-hexane-ethyl acetate)

Sources & evidence

ORD record
ord-0452f1ce872148fda593e1e777e3d9fe
Source dataset
uspto-grants-1990_11
Patent number
US04973600

Reaction notes

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