The oxidation of dithiocarbamato complexes of nickel, copper and zinc

Abstract

Abstract Oxidation of N,N ‐di‐ n ‐butyldithiocarbamato (bu 2 dtc) complexes of Cu(I), Ni(II), Zn(II), Cd(II) and Hg(II) is reported. Oxidation of Ni(bu 2 dtc) 2 with Cl 2 , Br 2 , or of NiX 2 (X = Cl, Br, NO 3 ) with N,N,N′,N ′‐tetra‐ n ‐butylthiuram disulfide (bu 4 tds) gives complexes of composition [Ni(bu 2 dtc) 3 ]X. These compounds are diamagnetic and dissolve in nitrobenzene as 1:1 electrolytes, their UV spectra resemble that of the iso‐electronic Co(bu 2 dtc) 3 . The experimental data are in accord with the assumption that in these compounds Ni(IV) flow spin d 6 ) is surrounded by 6 S atoms in octahedral symmetry. The analogous selenium compound tris ( N, N ‐di‐ n ‐butyldiselenocarbamato) nickel(IV) bromide, having the same properties as the thio compounds, can also be prepared. Oxidation of Cu(bu 2 dtc) with Cl 2 or Br 2 yields paramagnetic products with the composition CuX 3 (bu 2 dtc), in which Cu also has the formal oxidation number + 4, but the structure of these compounds is still obscure. Oxidation of Zn(bu 2 dtc) 2 and the corresponding Cd and Hg compounds yields products, the analysis of which suggests the composition MX 2 (bu 2 dtc) 2 (M = Zn, Cd or Hg, X = Br or I), but infrared studies indicate that the dithiocarbamato ligands of the starting substances are oxidized to bu 4 tds, which in the reaction products is coordinated to the metal in its normal oxidation state + 2.