Water → (E)-4-bromo-3-(2-chloro-phenoxy)-but-2-enoic acid ethyl ester

HRID 18996

Reaction equation

HRID 18996 reaction equation
[CH2:1]([O:3][C:4](=[O:16])/[CH:5]=[C:6](/[O:8][C:9]1[CH:14]=[CH:13][CH:12]=[CH:11][C:10]=1[Cl:15])\[CH3:7])[CH3:2].[Br:17]N1C(=O)CCC1=O.O>ClCCl.N(C(C)(CC(C)C)C#N)=NC(C)(CC(C)C)C#N>[CH2:1]([O:3][C:4](=[O:16])/[CH:5]=[C:6](/[O:8][C:9]1[CH:14]=[CH:13][CH:12]=[CH:11][C:10]=1[Cl:15])\[CH2:7][Br:17])[CH3:2]

Participants

6

Reactant 3

HCID 962WaterHCID 67184N-bromobutanimideHCID 66894719(E)-3-(2-chloro-phenoxy)-but-2-enoic acid ethyl ester

Product 1

HCID 66895331(E)-4-bromo-3-(2-chloro-phenoxy)-but-2-enoic acid ethyl esterYield 113%

Reagents, catalysts & solvents 2

HCID 915372,2'-Azobis(2,4-dimethylvaleronitrile)CatalystHCID 6344DichloromethaneSolvent

Procedure

To a solution of (E)-3-(2-chloro-phenoxy)-but-2-enoic acid ethyl ester (1880 g, 7.82 mol) in dichloromethane (18.6 L) was added N-bromosuccinimide (1490 g, 8.29 mol) and 2,2′-azobis(2,4-dimethylvaleronitrile) (47 g, 0.188 mol) and the resulting solution heated to reflux for 23 h. The light yellow solution was cooled to room temperature and transferred to an extractor before water (19 L) was added. The biphasic mixture was stirred at room temperature for 1 h. The mixture was separated and the organic phase washed with a 20% sodium chloride solution (19 L). The solution was evaporated to give (E)-4-bromo-3-(2-chloro-phenoxy)-but-2-enoic acid ethyl ester (87.8% pure by HPLC, 2824 g, 99%) as a red oil.

Workup

  1. temperaturethe resulting solution heated
  2. temperatureto reflux for 23 h
  3. additionwas added
  4. customThe mixture was separated
  5. washthe organic phase washed with a 20% sodium chloride solution (19 L)
  6. customThe solution was evaporated

Sources & evidence

ORD record
ord-1cf7c89fa3a8465e90568a968c046442
Source dataset
uspto-grants-2010_06
Patent number
US07741327B2

Linked notes

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