Iodine, dithiocarbamate complexes

Tris(dithiocarbamate) complexes, [Cr(S2CNR2)3] (R = Et, Bz R2 = C4HgO), react with iodine in dichloromethane to form 1 1 complexes, as shown by spectrophotometric studies. The interaction results in charge transfer between the iodine and a sulfur atom (745). 

Reactions of tris(dithiocarbamate) complexes with iodine have been studied in some detail and lead to a range of products, being dependent on the conditions utihzed and substituents on the dithiocarbamate ligands, as discussed more fully in Section IV.E.l.b. 

As eluded to above, reactions of tris(dithiocarbamate) complexes with iodine have previously been shown to generate a variety of products (1199). Petridis et al. (1244) showed that in dichloromethane, [Fe(S2CNMe2)3] yields a product of the formula, [Fe(S2CNMe2)2l2], while in contrast, [Fe(S2CNEt2)3] affords [Fe(S2CNEt2)2l3l (254) (Fig. 147). Mossbauer parameters for the latter suggest a... 

Tris(dithiocarbamate) complexes are readily oxidized (see below), however, upon addition of iodine only simple adducts, [Co(S2CNR2)3].2l2 (R = Me, Et R2 = C5H10, C4HgO), result. The dimethyldithiocarbamate complex has been... 

Trithiocarbonato complexes resemble in their reactions and properties other 1,1-dithiolo complexes such as those of xanthates and dithiocarbamates (see Chapter 16.4). Oxidation of [Ni(CS3)2]2- by iodine or elemental sulfur yields [Ni(CS4)2]2-, which probably has the structure (44). The frequency v(S—S) occurs at 480 cm-1 in the Raman spectrum, while v(C—S) occurs at 1035 cm-1, i.e. at slightly higher energy than in the spectrum of [Ni(CS3)2]2-. The complex (Ph4 As)2-[Ni(CS4)2] can also be prepared from KCS4.148... 

Work by Paul Beer et al. in Oxford on dithiocarbamate-functionalised resorcarenes has resulted in resorcarene trimers termed molecular loops and molecular tetrahedra composed of four resorcarene units. The molecular loops (pyridine-capped Cd(II) and Zn(II) complexes) can bind C60 which fits neatly into the 16.4 A wide central cavity.35 The slightly larger tetrahedral tetramer which has a 19.4 A edge length, compared to 19.1 A for the loop, is bridged by square planar copper(III) ions, a very unusual oxidation state of copper that is obtained from iodine oxidation of an intermediate copper(II) complex. The solid-state structures of examples of the loop and tetrahedron are shown in Figure 10.35. 

---