Abstract: Novel vanadium(IV) oxide bis(dialkyldithiocarbamates) of the formula ##STR1## which R and R.sup.1 denote identical or different, branched or straight-chain, saturated or unsaturated alkyl radicals having 1-18 carbon atoms or cycloalkyl radicals having 4-7 carbon atoms, with the proviso that R.sup.1 is not identical to R when R is C.sub.1 -C.sub.4 -alkyl, cyclobutyl or cyclohexyl, are prepared by a process comprising reacting 2 mols of an alkali metal dialkyldithiocarbamate of the formula ##STR2## in which R and R.sup.1 are as defined above and Me represents sodium, potassium or ammonium, with 1 mol of vanadium(IV) oxide sulfate pentahydrate in methanol or water as a solvent. The novel vanadium dithiocarbamates can be used as additives for permanent gear lubricating oils or hydraulic fluids to prolong the life of such oils.

Abstract: Novel tungsten hexa(dialkyldithiocarbamates) of the general formula I ##STR1## in which R and R.sup.1 can be identical or different, branched or straight-chain, saturated or unsaturated alkyl radicals having 1-18 carbon atoms are prepared by a process in which 6 mols of an alkali metal dialkyldithiocarbamate of the general formula II ##STR2## in which R and R.sup.1 are as signified above and Me can be sodium, potassium or ammonium, are reacted with 1 mol of tungsten hexachloride in a solvent which is inert with respect to the reaction. The alkali metal chloride or ammonium chloride formed is separated off and the tungsten hexa(dialkyldithiocarbamate) is isolated. The tungsten hexa(dialkyldithiocarbamates) of the invention can be used as additives for prolonging the life of hydraulic oils or permanent gear lubrication oils.