Thionyl Chloride → 5-(Chlorosulfonyl)-2-ethoxybenzoic acid

Participants

Reaction Steps

Molten 2-ethoxybenzoic acid (25.0 g, 0.150 mol) was added to a stirred, ice-cooled mixture of thionyl chloride (11 ml, 0.151 mol) and chlorosulphonic acid (41.3 ml, 0.621 mol), whilst maintaining the temperature of the reaction mixture below 25° C. The resulting mixture was stirred at room temperature for 18 hours and then poured into a stirred mixture of ice (270 g) and water (60 ml) to give an off-white precipitate. Stirring was continued for 1 hour, then the product was collected by filtration, washed with water and dried under vacuum to provide the title compound (36.08 g). A reference sample, m.p. 115-116° C. was obtained by crystallisation from hexane:toluene. Found: C, 41.02; H, 3.27. C9H9ClO5S requires C, 40.84; H, 3.43%. δ (CDCl3): 1.64 (3H, t), 4.45 (2H, q), 7.26 (1H, d), 8.20 (1H, dd), 8.80 (1H, d).

Provenance & Evidence