Dithiocarbonsäuren und Dithiocarbonsäureester sowie Thiocarbonsäureamide aus methylenaktiven Chlormethylverbindungen und Schwefel

The direct sulphurization of chloromethyl compounds with elemental sulphur leads to dithiocarboxylic acids, dithiocarboxylic esters or thioamides. In the presence of a base, the starting products can be oxidized by low-temperature sulphurization, a reaction of wide application. The conversion of chloroacetic acid and its derivatives to thiooxalic derivatives, activated C2-building blocks of growing interest in synthetic chemistry, is of special importance. As a rule, the examples described in the review have not been published. They show a new and easy way for the preparation of heterocycles containing activated dithiocarboxylic functions.