Hydrochloric Acid → Ethyl chloro(hydroximino)acetate

Participants

Reaction Steps

Ethyl chlorohydroxyiminoacetate (ECHA) can be produced from glycine ethyl ester hydrochloride by the in-situ generation of nitrosyl chloride gas from aqueous sodium nitrite and HCl. In particular, Glycine ethyl ester.HCl is dissolved in water. To this is added concentrated HCl solution (32%) and the reaction mixture is cooled to <10° C. HCl gas is then bubbled into the reaction mixture. An aqueous solution of sodium nitrite is dosed into the reactor while maintaining the temperature at <10° C. HCl gas is bubbled into the reactor again followed by a second portion of aqueous sodium nitrite. Finally, the product is purified from the reaction mixture by any appropriate means known to those of skill in the art. For example, the reaction mixture is stirred for a further period and then extracted with a water immiscible solvent (dichloroethane, chloroform, carbon tetrachloride) at room temperature to remove the product from the reaction mixture. The organic extracts are dried with a drying agent and the solvent is flashed off. An oily residue remains, which crystallizes on cooling. The crystals are filtered and washed with a suitable solvent to obtain a purified ECHA.

Provenance & Evidence