Chlorosulfonic acid → HCID 86612878, compound

Participants

Reaction Steps

2-Ethoxy-4-methoxybenzoic acid (9.5 g, 48.5 mmol) was added in portions to cold chlorosulfonic acid (60 mL, Aldrich) stirring at −3 to 0° C. (ice-acetone bath) over 15 min and warmed slowly to room temperature and heated to 60-65° C. for 40 min. The resulting dark solution was carefully poured with stirring into a large excess of ice and then 500 mL of dichloromethane was added. After stirring for 15 min, the layers were separated and the aqueous layer was extracted with dichloromethane (3×250 mL). The organic layers were washed with brine and dried over anhydrous magnesium sulfate. The solids were filtered off, and the filtrate was evaporated to a low volume. This was triturated with ether/hexane and filtered to give 5-chlorosulfonyl-2-ethoxy-4-methoxybenzoic acid as a colorless solid (13.4 g, 94%).

Provenance & Evidence