GB687069A - Improvements in and relating to the manufacture of 2:3-dimercaptopropanol derivatives - Google Patents

Abstract

A water-soluble derivative of 2 : 3-dimercapto propanol is prepared by heating a mixture of approximately equimolecular proportions of 2 : 3-dimercapto propanol and succinic anhydride, and reacting the acidic product formed with a basic material to form a water-soluble salt, e.g. an alkali metal salt. The initial reaction is preferably effected in an inert atmosphere; an inert organic solvent may be present. The acidic product of the initial reaction may be purified, e.g. by dissolving the product in aqueous alkali carbonate, acidifying the solution, thereby precipitating the acid product and extracting the latter with, say, chloroform. Formation of the salt is preferably effected in absence of water, e.g. by using an alcoholic solution of a sodium alkoxide to neutralize an alcoholic solution of the acidic product, the concentrations being such that the desired salt then precipitates out. In an example, succinic anhydride and 2 : 3-dimercapto-propanol are heated together in an atmosphere of nitrogen on a steam bath and the acidic product converted into the sodium salt which is stated to have about 1/16 th of the toxicity of 2 : 3-dimercaptopropanol. Specification 623,377 is referred to.