Thiuram disulfides copper complexes

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. 

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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