Ethyl bromoacetate → 3-Carbamoyl-2,4,6-triiodophenoxyacetic acid

HRID 2296497Notes

Reaction equation

HRID 2296497 reaction equation
[Na].[OH:2][C:3]1[C:4]([I:14])=[C:5]([C:9]([I:13])=[CH:10][C:11]=1[I:12])[C:6]([NH2:8])=[O:7].Br[CH2:16][C:17]([O:19]CC)=[O:18]>C(O)C>[C:6]([C:5]1[C:4]([I:14])=[C:3]([C:11]([I:12])=[CH:10][C:9]=1[I:13])[O:2][CH2:16][C:17]([OH:19])=[O:18])(=[O:7])[NH2:8]

Participants

5

Reactant 3

HCID 7748Ethyl bromoacetateHCID 5360545SodiumHCID 198483713-Hydroxy-2,4,6-triiodobenzamide

Product 1

HCID 198483573-Carbamoyl-2,4,6-triiodophenoxyacetic acidYield 93.7%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

0.436 g (19 mmol) of sodium is dissolved in 20 ml of ethanol. Then 9.78 g (19 mmol) of 3-hydroxy-2,4,6-triiodobenzamide and subsequently 3.5 g (21 mmol) of ethyl bromoacetate are added thereto. The mixture is heated for one hour to reflux and, after several hours of stirring in an ice bath, the resultant 3-carbamoyl-2,4,6-triiodophenoxyacetic acid ethyl ester is vacuum-filtered, washed with a small amount of ice-cold ethanol, and suspended in 80 ml of water. The mixture is brought to pH 12 by adding concentrated sodium hydroxide solution, stirred for 30 minutes at 60° C., the solution is treated with 1 g of active carbon, filtered, and brought to pH 1 by the dropwise addition of dilute hydrochloric acid. After several hours of stirring in an ice bath, the thus-formed precipitate is vacuum-filtered, washed with water, and dried, thus obtaining 10.2 g (89% of theory) of 3-carbamoyl-2,4,6-triiodophenoxyacetic acid as a white powder, mp 211°-213° C. (decomposition).

Workup

  1. temperatureThe mixture is heated for one hour
  2. temperatureto reflux and, after several hours
  3. filtrationthe resultant 3-carbamoyl-2,4,6-triiodophenoxyacetic acid ethyl ester is vacuum-filtered
  4. washwashed with a small amount of ice-cold ethanol
  5. additionby adding concentrated sodium hydroxide solution
  6. stirringstirred for 30 minutes at 60° C.
  7. additionthe solution is treated with 1 g of active carbon
  8. filtrationfiltered
  9. additionbrought to pH 1 by the dropwise addition of dilute hydrochloric acid
  10. stirringAfter several hours of stirring in an ice bath
  11. filtrationthe thus-formed precipitate is vacuum-filtered
  12. washwashed with water
  13. customdried

Sources & evidence

ORD record
ord-946de0768a674802ba61965ac8cd0520
Source dataset
uspto-grants-1984_01
Patent number
US04429152

Reaction notes

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