Sulfur ligands physical properties

Fig, 1 provides a listing of the various sulfur donor ligands whose complexes have been the subject of considerable research. The list of ligands in Fig. 1 is not exhaustive since only potentially bidentate ligands are given. The electronic properties of complexes with bidentate sulfur donor ligands are usually similar although their physical properties, e.g., solubility, can vary widely. This review deals primarily with dithio- and diselenophosphate complexes however, related complexes are discussed wherever they are pertinent to the present discussion. 

Analytical data on the soluble products isolated from chloroform are in excellent agreement with the composition 1 Ni+2 1 monoalkylated ligand 1 I or Br. The magnetic moment of this methylated complex was found to be 1.89 Bohr magnetons per nickel (II). The molar conductivities of the methylated and benzylated complexes in methanol at 25° C. are 75.4 and 68.4 ohm-1, respectively. These values approximate those expected for uni-univalent electrolytes in this solvent. The formulation of these alkylated compounds as dimeric electrolytes (structure VII) does not appear to be totally consistent with their physical properties. One or both halide ions may be bound to the metal ion. These results lead to the easily understood generalization that terminal sulfur atoms alkylate more readily than bridged mercaptide groups. 

As expected the physical properties of the sulfur derivatives 55 are very similar to those of the corresponding lanthanide(III) benzamidinates 20. Apparently no attempts have been made so far to prepare disubstituted lanthanide complexes containing diiminosulfinate ligands. 

Physical properties of mesogens with bidentate sulfur ligands Benzoato complexes Tropolone complexes... 

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