Chlorosulfonic acid → 4-Chloro-5-chlorosulfonyl-2-ethoxybenzoic acid

HRID 2263925Notes

Reaction equation

HRID 2263925 reaction equation
[Cl:1][C:2]1[CH:10]=[CH:9][C:5]([C:6]([OH:8])=[O:7])=[C:4]([O:11][CH2:12][CH3:13])[CH:3]=1.[Cl:14][S:15](O)(=[O:17])=[O:16]>ClCCl>[Cl:1][C:2]1[C:10]([S:15]([Cl:14])(=[O:17])=[O:16])=[CH:9][C:5]([C:6]([OH:8])=[O:7])=[C:4]([O:11][CH2:12][CH3:13])[CH:3]=1

Participants

4

Reactant 2

HCID 24638Chlorosulfonic acidHCID 189546044-Chloro-2-ethoxybenzoic acid

Product 1

HCID 866128774-Chloro-5-chlorosulfonyl-2-ethoxybenzoic acid

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Conditions

Temperature
5 °C

Procedure

4-Chloro-2-ethoxybenzoic acid (9.4 g, 47 mmol) was added in several portions to cold chlorosulfonic acid (55 mL, Aldrich) stirring at 0-10° C., and the resulting solution was heated at ˜60° C. for 2 h. The resulting dark solution was poured into ice (800 g), and then 500 mL of dichloromethane was added. After stirring for 15 min, the layers were separated and the aqueous layer was extracted with 200 mL of dichloromethane. The organic layers were washed in turn with brine, combined, dried over magnesium sulfate, filtered, and concentrated at room temperature. Crystallization from ether/hexane gave 3.4 g of 4-chloro-5-chlorosulfonyl-2-ethoxybenzoic acid.

Workup

  1. temperaturethe resulting solution was heated at ˜60° C. for 2 h
  2. stirringAfter stirring for 15 min
  3. customthe layers were separated
  4. extractionthe aqueous layer was extracted with 200 mL of dichloromethane
  5. washThe organic layers were washed in turn with brine
  6. dry with materialdried over magnesium sulfate
  7. filtrationfiltered
  8. concentrationconcentrated at room temperature
  9. customCrystallization from ether/hexane

Sources & evidence

ORD record
ord-97f5c11b03684e6b9c6e1bf8ef197155
Source dataset
uspto-grants-2010_12
Patent number
US07851626B2

Reaction notes

Loading…