Ethylenebis(dithiocarbamates)

History

The ethylenebisdithiocarbamates were rediscovered in 1945 when Dimond et al. (2) reported a “new water soluble protectant fungicide.” The parent compound, disodium ethylenebisdithiocarbamate, was highly soluble in water and was unstable in air, and it might have been only a laboratory curiosity and remained unnoticed but for the applications developed by Heuberger and Manns (3), who stabilized it by converting it into zinc salt by the addition of zinc sulfate–lime mixture. This was followed by the introduction of zineb as fungicide by the Rohm and Haas Company, USA. The same phenomenon was later confirmed by Barratt and Horsfall (4), who attributed the stabilizing effect as due to zinc salt formation. From the numerous compounds suggested by Hester (5), only disodium ethylenebisdithiocarbamate and its zinc and manganese salts are largely accepted for practical application. Research on these dithiocarbamates led to some promising variants.

Uses

Ethylenebisdithiocarbamates have strong metal binding capacity and act as inhibitors of enzymes. They have a profound effect on biological systems, and so they are widely used in medicine and in agriculture as fungicides (6). Their residues on food and fodder are hazardous and may potentially cause chronic damage to health, because humans consume these items as a part of their normal dietary intake and ethylenebisdithiocarbamates are widely used as fungicides. Therefore, their residues must be closely checked because their persistent, as well as cumulative, action may be harmful. Some of the most-used ethylenebisdithiocarbamate fungicides are nabam [disodium ethylenebis (dithiocarbamate)], mancozeb [manganese/zinc ethylenebis (dithiocarbamate)], and maneb [manganese ethylenebis (dithiocarbamate)].

Raw materials

Preparation Products