Thiuram disulfides copper

The reaction of metallic copper with thiuram disulfides yields complexes of Cu I), which are polymeric in solution as well as in the solid state 121,122). In 123) the copper atoms are located at the corners of a slightly distorted tetrahedron with Cu—Cu distances ranging from 2.6—2.7 A. Each of the copper atoms is coordinated to three sulfur atoms in a nearly planar triangular arrangement and each sulfur atom coordinates one or two copper atoms. 

Since isolable organocopper) 11) compounds do not apparently exist, it is rather surprising that oxidation of the cuprate CdI+[(CF3)2Cu ] (prepared in situ) with thiuram disulfide affords (CF3)2Cu "S2CNEt2 (see Eqn. 1 in Scheme 1.6), the first and so far only example of an organocopper compound with the copper atom in the trivalent oxidation state. The structure of this compound was unambiguously proven by an X-ray crystal structure determination (see Fig. 1.2) [37]. 

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). 

KD-110. See N-Phenyl-N -(1-methylheptyl)-p-phenylenediamine KD-112. See Epoxidized soybean oil KD-128. See Dibenzylamine KD-130. See Dibutyl phthalate KD-144. See Dibutyl sebacate KD-162. See N,N -Di (n-octyl)-p-phenylenediamine KD-206. See Butyl oleate KD-227. See n-Dioctyl phthalate KD-234. See Trial Iylcyan urate KD-242. See Tetrabutyl thiuram disulfide KD-296. See Diethylene glycol KD-318. See Diphenylamine-acetone KDCC. See Potassium dichloroisocyanurate Kelcal-Ace. See Calcium silicate KELACID . See Alginic acid Kelate 220. See Tetrasodium EDTA Kelate Acid. See Edetic acid Kelate CDS. See Calcium disodium EDTA Kelate Cu Liq.. See Disodium EDTA-copper... 

Casey and Vecchio (186,187) developed the oxidative-addition of thiuram disulfides to metals in order to produce a one-step preparation of a wide range of transition metal dithiocarbamate complexes. In this way, [Ni(S2CNMe2)2] and [Zn(S2CNMe2)2] can be prepared in near quantitative yields. With copper, only the copper(II) species are seen, and this is in keeping with Akerstrom s (188) earlier observation that copper(I) species react instantaneously with thiuram disulfides to generate the analogous copper(II) complexes. 

Victoriano et al. (1711,1712) reported that addition of thiuram disulfides to copper(I) halides gives mixed-valence complexes [Cu(S2CNR2)2][CuX (S2CNR2)] (R = Me, Et X = Cl, Br) containing one copper(III) and a second copper(II) center. Upon thermolysis (R = Me), electron transfer occurs generating the black copper(II) dimer [Cu(S2CNMe2)(p-Cl)]2 (Peff 1-81 BM) and one-half of an equivalent of tetramethylthiuram disulfide. 

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