Ethanolamine → N-(2-hydroxyethyl)benzenesulfonamide

Participants

Reaction Conditions

Reaction Steps

128.3 g of 2-ethanolamine (2.1 mol) and 150 g of water are introduced into a 1 litre reactor equipped with a thermostatically-controlled jacket, a stirrer and a dropping funnel. 353 g of benzenesulphonyl chloride (2 mol) are introduced into the dropping funnel. The reactor is heated to approximately 60° C. and the benzenesulphonyl chloride is then allowed to run dropwise into the reactor at the rate of approximately 3 ml/min. The exothermicity of the reaction is thus controlled and the temperature changes to reach 70 to 75° C. at the end of addition. The pH is prevented from falling below 9 by gradual addition of a 20% solution of sodium hydroxide in water. After a few hours, the reaction is complete. The reaction mixture is then extracted with a third water-insoluble solvent, such as ethyl acetate. This organic phase is collected. The aqueous phase is extracted and the combined organic phases are distilled under vacuum in order to remove the extraction solvent. 384 g of N-(2-hydroxyethyl)benzenesulphonamide are thus obtained, i.e. a yield of 95.5% with a purity of greater than 99%. This product, which is liquid at room temperature, is characterized by IR spectroscopy and NMR spectro-scopy, as well as by GC and HPLC analysis.

Provenance & Evidence