Organic ligand properties

Cyanato-copper(II) complexes with nitrogen organic ligands preparation, properties and structure. J. Kohout, M. Hvastijova and J. Gazo, Coord. Chem. Rev., 1978, 27,141-172 (116). 

Having thus illustrated the use of organic ligands as fluorescent sensors, we will now consider the applications of the photophysical properties of coordination compounds themselves. All the... 

Owing to the good ligand properties of isocyanides for complexation of gold(i), complexes of the type [(RNC)2Au]+X are readily available through a variety of synthetic routes. One new approach is the substitution of organic nitriles. The reaction is carried out in acetonitrile and gives quantitative yields (Equation (43)).2... 

Following the original paper, reports of the synthesis of new crowns and crown-like molecules proliferated. A typical property of these systems is their ability to form stable complexes with the alkali metal and alkaline earth ions. Prior to the synthesis of the crowns, the coordination chemistry of the above ions with organic ligands had received very little attention. A further impetus to the study of such complexes was the recognition of the important role of Na+, K+, Mg2+ and Ca2+ ions in biological systems. 

This review is an attempt to rationalize the main reaction patterns observed so far in organonickel chemistry. Synthetic work in organic chemistry has found an exceedingly valuable tool in the use of nickel complexes. The reason for this lies in the fact that nickel possesses a very favorable combination of properties to meet the requirement for an organic reaction to take place via coordination. Let us consider, for example, which basic steps occur when organic ligands react on a transition metal to form C—C bonds. 

Redox reactions usually lead, however, to a marked change in the species, as reactions 4-6 indicate. Important reactions involve the oxidation of organic and metalloprotein substrates (reactions 5 and 6) by oxidizing complex ions. Here the substrate often has ligand properties, and the first step in the overall process appears to be complex formation between the metal and substrate species. Redox reactions will often then be phenomenologically associated with substitution. After complex formation, the redox reaction can occur in a variety of ways, of which a direct intramolecular electron transfer within the adduct is the most obvious. 

---