CH3CH2SO3

CH3CH2SO3 represents the ethylsulfonate anion. It is the conjugate base of ethanesulfonic acid (CH3CH2SO3H). Ethanesulfonic acid is a strong organic acid, meaning it readily dissociates in water to form the ethylsulfonate anion and a proton (H+). The ethylsulfonate anion is a stable species due to the delocalization of negative charge over the oxygen atoms of the sulfonate group. It is a relatively non-nucleophilic anion.

Salts containing the ethylsulfonate anion are known as ethylsulfonates. Examples include sodium ethylsulfonate (CH3CH2SO3Na) and potassium ethylsulfonate (CH3CH2SO3K). These salts are generally soluble in water and exhibit properties typical of alkali metal sulfonates. The ethylsulfonate anion can be found as a counterion in various chemical compounds and formulations. Its presence often confers water solubility or surfactant-like properties to the parent molecule. It is not typically associated with significant toxicity.