Dithiobenzoate ligands

There have only been a few examples of cobalt and rhodium complexes bearing dithiocarboxylato ligands, such as the cobalt complex 41 which bears a bridging dithiobenzoate ligand, as shown in Fig. 11 [87-91], while there are a few (interesting) examples of iridium complexes. Treatment of a stable iridabenzene... 

Various bidentate ligands like dithiocarbamate afford monomeric square planar complexes specific examples are Pt(S2CNEt2)2 and Pt(Se2CNBu)2 (confirmed by X-ray). A similar structure is found for the dithiobenzoate Pd(S2CPh)2 one form of the dithioacetate is dimeric, a second form is a mixture of monomers and dimers. 

Eventually we formed carbonyls in the liquid phase by redox disproportionation of nickel and cobalt derivatives of organic thioacids. In the reaction between nickel(II) dithiobenzoate and carbon monoxide in the presence of HS ion we assumed the formation of a sulfur-bridged nickel(IV) complex (VII, 32). More recent investigations (84), however, have shown that half the nickel appears as a monomeric nickel(II) complex of the same empirical formulation, formed by insertion of a sulfur atom in the dithio ligand, the other half of the nickel being reduced to nickel(O) by the sulfide. 

Complexes containing bidentate sulfur-bonded ligands which form four-membered rings with the manganese atom are obtained by the reaction between [MnBr(CO) 5] and dithiobenzoic acid(2 69a) or sodium N,N-dialkyl-dithiocarbamates (2696) the products have the compositions [Mn(S2CC jH 5) (CO)4] or [Mn(S2CNR2)(CO)4] (R = CH3, C2H5) respectively. 

Another potentially interesting ligand for transition metals is the recently reported dithiocarboxylate anion RfCSS (32), Treatment of in situ prepared RFLi with excess carbon disulfide results in the formation of a red-brown solution, from which RfCSSH can be isolated after acidification (55% yield). Pure 2,4,6-tris-(trifluoromethyl)dithiobenzoic acid forms a dark red oily liquid. Orange crystalline [CsHioNH2] RfCSS" has been prepared by neutralizing the free acid with piperidine in pentane solution (32), The coordination chemistry of the RfCSS" anion still awaits further investigation. 

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