Copper dimethyl dithiocarbamate

Copper dimethyl-dithiocarbamate Diphenylmethylene thiuram tetrasulfide... 

CN Cellulose nitrate (ASTM, DIN, ISO, CuDMC Copper dimethyl dithiocarbamate (WTR) ... 

A study in Japan looked at the migration of dimethylamine (DMA) into water and hydrochloric acid from 25 rubber articles (including stoppers, chopping boards, spatulas and teats). After one hour of refluxing, the water extracts contained 3 to 1280 mg of DMA per kg of rubber. The study also showed that the thiuram accelerators that were present (TMTD and TMTM) were almost totally decomposed to DMA (a nitrosatable substance). However, in the case of dimethyl dithiocarbamate salts (sodium, zinc, copper and lead examples were included), the decomposition to DMA depended on the solvent used and the salt compound. 

These are easily prepared by the reaction of amines with carbon disulfide (1) in the presence of alkali (Scheme 17).2 The synthesis of dithiocarba mates (4) was first reported by Debus in 1850. Dithiocarba mates (4) form metal chelates, and sodium dimethyl dithiocarbamate is used in quantitative inorganic analysis for the estimation of metals, e.g. copper and zinc. Dithiocarba mates are also employed as vulcanisation accelerators and antioxidants in the rubber industry, and as agricultural fungicides.3 The parent dithiocarbamic acids are unstable, decomposing to thiocyanic acid and hydrogen sulfide however, the salts and esters are stable compounds. Dithiocarba mates (4) are oxidised by mild oxidants to the thiuram disulfides (38) (Scheme 17). 

Penicillamine (D-(3,(3-dimethylcysteine) is an effective chelator of copper, mercury, zinc and lead which promotes the excretion of these metals in the urine. It is clinically used in patients with Wilson s disease, with rheumatoid arthritis and with heavy-metal intoxications. Ziram and ferbam are the zinc and the iron salts respectively of dimethyl-dithiocarbamic acid (Figure 20.44). They are widely used as selective fungicides in agriculture. Pyrithione (1 -hydroxy-2(l//)-pyridinethione), as its zinc salt is used in dermatology as antiseborrheic. 

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