1,2-Dichloroethane → 4-(2-Chloro-ethoxy)-benzoic acid methyl ester

HRID 2289154Notes

Reaction equation

HRID 2289154 reaction equation
[CH3:1][O:2][C:3](=[O:11])[C:4]1[CH:9]=[CH:8][C:7]([OH:10])=[CH:6][CH:5]=1.C(=O)([O-])[O-].[K+].[K+].CS(C)=O.[Cl:22][CH2:23][CH2:24]Cl>O>[CH3:1][O:2][C:3](=[O:11])[C:4]1[CH:9]=[CH:8][C:7]([O:10][CH2:24][CH2:23][Cl:22])=[CH:6][CH:5]=1

Participants

6

Reactant 4

HCID 111,2-DichloroethaneHCID 679Dimethyl SulfoxideHCID 7456MethylparabenHCID 11430Potassium Carbonate3×

Product 1

HCID 64854314-(2-Chloro-ethoxy)-benzoic acid methyl ester

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

4-hydroxybenzoic acid methyl ester (1.52 g, 10 mmol), anhydrous potassium carbonate (1.38 g, 10 mmol), 10 ml of dimethylsulfoxide, and 20 ml of 1,2-dichloroethane are combined and heated to reflux. HPLC shows the reaction is at equilibrium at about 1 hour. Therefore, another equivalent of potassium carbonate is added. After the second addition of potassium carbonate, the ratio of product to bis alkylated biproduct is greatly enhanced. The reaction mixture is cooled to room temperature and diluted with 30 ml of water. The mixture is stirred then the layers separated. The organic layer is back extracted with 20 ml of brine and then filtered through sodium sulfate. The filtrate is concentrated in vacuo at about 60° C. to a yellow green oil which solidifies on cooling. This crude product is redissolved in 12 ml of hot methanol and water is added (total of 6 ml) dropwise until crystals appear. The crystallization is allowed to continue for one hour with cooling. The precipitate is filtered and rinsed with 12 ml of 1:1 methanol:water. The filter cake is dried in vacuo at about room temperature to give 2.00 g of product. (93.5%). HPLC.

Workup

  1. temperatureheated to reflux
  2. customthe layers separated
  3. extractionThe organic layer is back extracted with 20 ml of brine
  4. filtrationfiltered through sodium sulfate
  5. concentrationThe filtrate is concentrated in vacuo at about 60° C. to a yellow green oil which
  6. temperatureon cooling
  7. dissolutionThis crude product is redissolved in 12 ml of hot methanol
  8. additionwater is added (total of 6 ml) dropwise until crystals
  9. customThe crystallization
  10. waitto continue for one hour
  11. temperaturewith cooling
  12. filtrationThe precipitate is filtered
  13. washrinsed with 12 ml of 1:1 methanol
  14. customThe filter cake is dried in vacuo at about room temperature

Sources & evidence

ORD record
ord-f195f23f706b4463b5923afa303941ed
Source dataset
uspto-grants-2000_07
Patent number
US06090949

Reaction notes

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