Tris dithiocarbamic acid

Solutions of sodium tellurite in water1,2 or prepared from tellurium dioxide and aqueous sodium hydroxide3 were acidified with sulfuric acid and treated with freshly prepared solutions of bis[2-hydroxyethyl]dithiocarbamic acid in aqueous methanol. Addition of aqueous solutions of potassium chloride, iodide, or thiocyanate led to the deposition of crystalline tris[bis(2-hydroxyethyl)dithiocarbamate] halides. 

Tellurium Tris[bis(2-hydroxyethyl)dithiocarbamate] Iodide 20 ml (1 mmol) of a 0.05 molar aqueous solution of sodium tellurite are mixed with 50 ml of 1 molar sulfuric acid, 60 ml (30 mmol) of a 0.5 molar 20% aqueous/methanolic solution of bis[2-hydroxyethyl]dithiocarbamic acid. The mixture is stirred and 40 ml (4 mmol) of a 0.1 molar aqueous solution of potassium iodide arc added dropwise over 30 min. The red crystals deposited are collected, washed with water, and dried over sulfuric acid yield 0.8 g (100%) m.p. 160° (dec.)... 

Tellurium dioxide dissolved in hydrochloric or hydro bromic acid was treated with an excess of (V-methyl-iV-2-hydroxyethyldithiocarbamic acid in methanol. Yellow crystals of the tellurium tris[dithiocarbamate] halide precipitated1. 

Sodium tellurite dissolved in aqueous sulfuric acid reacted with a methanolic solution of the dithiocarbamic acid to produce the corresponding bis[tris(dithiocarbamato)tellurium] oxide1. 

Dithiocarbamic acid itself and its alkali metal salts are unstable towards hydrolysis but metal chelates are known and a structure of [Co(S,CNH2)3] is available (Table 96). This complex is probably unstable towards hydrolysis giving [Co(S2CO)3]3. Salts of dithiocarbamates derived from primary amines are also unstable under alkaline conditions, although N(3)-substituted dithiocar-bazic acid forms green tris(S,S) chelates (336).1133 The similar N(3)-unsubstituted acids form (N,S) chelates (337) which can be deprotonated when R = H with possible isomerization to the (S,S) dithiocarbimate chelate (339).1133 The (N,S) chelate (338) has been positively identified by a crystal structure of its 5-methyl ester, R = H (Table 96).1134... 

The compound is insoluble in all solvents but reacts with hydrohalic acids to form tellurium tris[dithiocarbamate] halides. ... 

Aminobenzothiazoles appeared unreactive toward carbon disulfide under base conditions (tri-ethylamine or pyridine). Nevertheless, when a superbasic medium consisting of sodium hydroxyde in an aprotic polar solvent, such as DMF, is used, a very fast reaction takes place. The resulting dithiocarbamic acid derivatives can be transformed into dithiocarbamates (170) or dithio-carbonimidates (171) by addition of one or two equivalents of methyl iodide, respectively (Scheme 41) <82S590>. 

The sulfur atoms in tris(dithiocarbamate) complexes can bind to Lewis acidic metal centers. For example, varying amounts of copper(I) iodide can be added to [Cr(S2CNR2)3] in acetonitrile to yield complexes in which sulfur atoms bridge... 

Tris(dithiocarbamate) complexes have also been also been prepared from unusual amines such as succinimide, phthalimide (49), l,4,7,10-tetraoxa-13-azacyclopentadecane (50), and a range of amino acids (138). Very recently. Beer et al. (62) prepared a number of novel tris(dithiocarbamate) complexes in which two iron(lll) centers are linked via the dithiocarbamate ligands (Fig. 145). 

A number of reactions of tris(dithiocarbamate) complexes have been investigated. Reduction of [Fe(S2CNR2)3] (R = Me, Et R2 = C4HgO, MePh) by oxalic acid in methanol-benzene proceeds with a first-order dependence on the... 

Bis(4-sulfobenzyl)dithiocarbamic acid Tri-Na salt, in B-00454 A -Phenylmethyl[[(4-chlorophenyl) amino]thioxomethyl]-A -phenylcarbamimidothioate, P-00145... 

Craig and co-workers247 reported the synthesis of l-aza-2,4,10-trithiaada-mantane (227) as a by-product in the reaction of ammonium dithiocarbamate with an aqueous solution of chloroacetaldehyde. The same compound is reported to be obtained by the reaction of mercaptoacetaldehyde with ammonia248 and then by the reaction of tri(2,2-bis(ethoxy)ethyl]amine (228) with hydrogen sulfide in the presence of hydrobromic acid.249 The... 

Several corrosion inhibitors such as polyamide, polyamine, dithiocarbamate, thiophosphate ester, organic acid, sulfide, and selenide types have all been tried in methanol without significant success [3.5]. Similarly, nonmetallic coatings of metals to effectively prevent corrosion have not been developed to date. One application where coatings have proven effective is in prevention of anodic dissociation of fuel pumps immersed in methanol. Since methanol is many times more conductive than gasoline, components such as fuel pumps and electrical fuel level gauges can cause induced currents that in turn remove metal from these... 

Ditellurium Tris[bis(2-hydroxyethyl) dithiocarbamate] Thiocyanate1 31 mg (0.1 mmol) of tellurium bis[bis(2-hydroxycthyl)dithiocarbamate] are dissolved in 5 ml of acetone. A solution of 0.29 g (3 mmol) of potassium thiocyanate in 10 ml of 3 M acetic acid is added. The reaction mixture is stirred and kept in a Petri dish at room temperature. Over night, deep-red, needle-shaped crystals separated. The crystals are filtered, washed with 1 M acetic acid and then with diethyl ether, and finally dried over anhydrous calcium chloride yield 80% dec. > 100° (TGA). The bromide and iodide derivatives were similarly prepared in the same yield. 

Tellurium was dissolved in aqueous sodium hydroxide. The solution was acidified with perchloric acid and an excess of sodium dialkyldithiocarbamate was added. Tris[dialkyl-dithiocarbamate] perchlorates of tellurium percipitated4. The X-ray structure analysis investigation of tellurium tris[dimethyldithiocarbamate] perchlorate revealed that all three dithiocarbamate groups and the perchlorate ion are bidentate4. 

Tris(pyrrolidine dithiocarbamato-)—cobalt(III) chelate, the precipitate formed by adding ammonium pyrrolidine dithiocarbamate to cobalt(II) solutions, has been found to be a good matrix for preconcentrating lead and several other metals by co-precipitation. Concentration factors of 40 to 400 are available by the method. The analyte is co-precipitated on the Co-APDC from a litre of sample. The precipitate is filtered on a fine porosity glass sinter and redissolved in a small volume of 6 M nitric acid. The solution is then used for atomic absorption analysis. 

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