Zinc complexes dithiolene

Subsequent to the development of the titanocene dithiolenes, related results were obtained starting with ZnS,(tmeda), where tmeda = tetrameth-ylethylenediamine and ZnS4(pmdta) (189), where pmdta = pentamethyldieth-ylenetriamine (ligand). These species react with DMAD and HC2C02Me to give dithiolene complexes, and the dithiolene can also be readily removed from the zinc center. The zinc complexes are more potent dithiolene-transfer agents than the titanocene complexes. The pentacoordinate complex ZnS4(pmdta) reacts more rapidly with alkynes than the tmeda derivative (Fig. 17). 

Homoleptic bis(dithiolene) complexes of d10 metal ions such as Cu(I), Zn(II), Cd(II), and Hg(II) are known. The tetrahedral zinc bis(dithiolene) complexes are among the best studied, and display much of the same CT photochemistry as the square-planar bis(dithiolene) complexes of the d8 metal ions (65, 66). The use of... 

The zinc tetrasulfido complex ZnS4(PMDETA) (PMDETA=pen-tamethyldiethylenetriamine) reacts with alkynes and CS2 to give the dithiolene complexes ZnS2C2(C02Me)2(PMDETA) and ZnS3CS(PMDETA), respec-... 

The linear dichroism of nickel(II), palladium(II) and zinc(II) complexes of mesomorphic 4-alkoxydithiobenzoic acids has been investigated in the commercial eutectic mixture of cyanobiphenyls and cyanoterphenyls, E7 (from Merck) for the palladium(II) complexes and in the commercial mixture of cyanobicyclohexanes, ZLI2830 (from Merck) for the nickel(II) and zinc(II) complexes (Figure 2.12).For the nickel(II) and palladium(II) complexes both a ligand-based transition and a charge-transfer band (MLCT) were observed, whereas only a ligand-based transition was present for the zinc(II) complexes. These complexes had a much lower solubility in the liquid crystal host matrix than the dithiolene... 

As with the dithiolene complexes of divalent zinc and cadmium, solvated electrons are also observed in the photolysis of dithiolene complexes of nickeKII)/ " The S-alkyl dithiolene complexes of nickel(II) also show interesting photochemistry. For these complexes, photolysis results in cleavage of the S-alkyl The reaction occurs in a stepwise sequence where the slow... 

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