GB460389A - Improvements in or relating to the formation of n-diaryl dithiocarbamates of metals - Google Patents

Abstract

Metal salts of diarylthiocarbamic acids are prepared by the action of carbon bisulphide on metal compounds of diarylamines. The term diarylamines includes all secondary amines in which the amino group is linked directly to two aromatic nuclei, the specified diarylamines being diphenylamine, phenyltolylamines, phenylcumylamines, phenylxenylamines, phenylnaphthylamines, phenylanthracylamines, ditolylamines, dixenylamines, dinaphthylamines, phenylar - tetrahydronaphthylamines, di-ar-tetrahydronaphthylamines, carbazole, o-iminodibenzyl, ms-ms-dimethylacridane, and thiodiphenylamine; diarylamines containing substituents, e.g. halogen atoms or nitro, alkoxy, aryloxy or secondary or tertiary amino groups may also be used. The metal compounds of the diarylamines may be prepared (1) by heating the diarylamine with a metal in the presence or absence of a catalyst, which may be iodine or a salt of iron, cobalt or copper, or (2) by heating the diarylamine with a metal amide or nitride. The alkali and alkaline earth metals, including magnesium, are the preferred metals. The reaction of diarylamine metal compound with carbon bisulphide is preferably effected in a solvent, e.g. a hydrocarbon or an excess of amine. In the examples: (1) diphenylamine is boiled under reflux with sodium and the product is treated at about 90 DEG C. with carbon bisulphide after addition of benzene; sodium diphenyldithiocarbamate is obtained; (2) diphenylamine containing a trace of iodine is boiled under reflux with magnesium and the product is treated with carbon bisulphide after dilution with benzene; magnesium diphenyldithiocarbamate is obtained; (3) phenyl - b - naphthylamine is heated with sodamide and the product is treated with carbon bisulphide; sodium phenyl-b -naphthyldithiocarbamate is obtained. The products may be subjected to double decomposition to convert them into salts of other metals, e.g. zinc or lead, or they may be acidified to yield the free acids. They may also be converted into esters by reaction with halogenated hydrocarbons, or into mixed anhydrides by reaction with acid halides, or into thiuram disulphides by oxidation, or into thiuram polysulphides by reaction with sulphur chloride.