Tetra-n-butylammonium tribromide → 2,6-Dichloro-3-bromo-4-aminobenzoic acid methyl ester

HRID 24721

Reaction equation

HRID 24721 reaction equation
[CH3:1][O:2][C:3](=[O:13])[C:4]1[C:9]([Cl:10])=[CH:8][C:7]([NH2:11])=[CH:6][C:5]=1[Cl:12].[Br-:14].[Br-].[Br-].C([N+](CCCC)(CCCC)CCCC)CCC.C([N+](CCCC)(CCCC)CCCC)CCC.C([N+](CCCC)(CCCC)CCCC)CCC>C(Cl)Cl>[CH3:1][O:2][C:3](=[O:13])[C:4]1[C:5]([Cl:12])=[CH:6][C:7]([NH2:11])=[C:8]([Br:14])[C:9]=1[Cl:10]

Participants

4

Reactant 2

HCID 23500184Tetra-n-butylammonium tribromideHCID 51341879Methyl 4-amino-2,6-dichlorobenzoate

Product 1

HCID 543430232,6-Dichloro-3-bromo-4-aminobenzoic acid methyl esterYield 139.4%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Procedure

To a solution of 2,6-dichloro-4-aminobenzoic acid methyl ester (2.80 g) in CH2Cl2 (20 mL) at −10° C. was added a solution of tetrabutylammonium tribromide (6.94 g) in CH2Cl2 (30 mL) dropwise at −10° C. After 2 h, the mixture was warmed to room temperature, washed with satd. NaHCO3 and brine, dried (Na2SO4), filtered, and concentrated. The residue was purified by column chromatography (silica gel; eluent: EtOAc/hexane 1:4) to yield 2,6-dichloro-3-bromo-4-aminobenzoic acid methyl ester (2.99 g) ESMS: m/z 298 (MH+).

Workup

  1. washwashed with satd
  2. dry with materialNaHCO3 and brine, dried (Na2SO4)
  3. filtrationfiltered
  4. concentrationconcentrated
  5. customThe residue was purified by column chromatography (silica gel; eluent: EtOAc/hexane 1:4)

Sources & evidence

ORD record
ord-dbc596b7032f48c9b0d9fb4f579b2e8c
Source dataset
uspto-grants-2005_02
Patent number
US06855843B2

Linked notes

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