Benzocaine → Ethyl 4-amino-3-bromobenzoate

HRID 1455132Notes

Reaction equation

HRID 1455132 reaction equation
[Br:1]Br.[NH2:3][C:4]1[CH:14]=[CH:13][C:7]([C:8]([O:10][CH2:11][CH3:12])=[O:9])=[CH:6][CH:5]=1>ClCCl.O>[NH2:3][C:4]1[CH:5]=[CH:6][C:7]([C:8]([O:10][CH2:11][CH3:12])=[O:9])=[CH:13][C:14]=1[Br:1]

Participants

5

Reactant 2

HCID 2337BenzocaineHCID 24408Bromine

Product 1

HCID 242793Ethyl 4-amino-3-bromobenzoateYield 88%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6344DichloromethaneSolvent2×

Procedure

A solution of bromine (7.0 mL, 137.3 mmol) in dichloromethane is added dropwise to a cold (−10° C.) solution of ethyl 4-aminobenzoate (22.0 g, 133.3 mmol) in dichloromethane. The reaction mixture is allowed to come to room temperature, stirred for 18 h and diluted with water. The organic phase is separated, washed twice with brine, dried over MgSO4 and concentrated in vacuo. The resultant residue is purified by flash chromatography (SiO2, 8/1 hexanes/EtOAc as eluent) to afford the title compound as a white solid, 28.6 g (88% yield), identified by HNMR and mass spectral analyses. MS m/e 242 (M−H)+; 1H NMR (400 MHz, DMSO-d6) δ 1.28 (t, J=7.01 Hz, 3H), 4.22 (q, J=7.16 Hz, 2H), 6.18 (brs, 2H), 6.81 (d, J=7.91 Hz, 1H), 7.65 (dd, J=8.54, 1.98 Hz 1H), 7.89 (d, J=1.83 Hz, 1H).

Workup

  1. customto come to room temperature
  2. customThe organic phase is separated
  3. washwashed twice with brine
  4. dry with materialdried over MgSO4
  5. concentrationconcentrated in vacuo
  6. customThe resultant residue is purified by flash chromatography (SiO2, 8/1 hexanes/EtOAc as eluent)

Sources & evidence

ORD record
ord-c8611048327b40bbb97014bd9e615a4d
Source dataset
uspto-grants-2009_01
Patent number
US07482349B2

Reaction notes

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