Phenols ligand property

Electropolymerization is also an attractive method for the preparation of modified electrodes. In this case it is necessary that the forming film is conductive or permeable for supporting electrolyte and substrates. Film formation of nonelectroactive polymers can proceed until diffusion of electroactive species to the electrode surface becomes negligible. Thus, a variety of nonconducting thin films have been obtained by electrochemical oxidation of aromatic phenols and amines Some of these polymers have ligand properties and can be made electroactive by subsequent inincorporation of transition metal ions... 

Bis 8-quinolmato metal complexes are representative examples of distorted octahedral structures of the type (87). It was noted that these systems bear a topological resemblance to the chiral, octahedral, active metal sites that have been proposed for supported Ziegler-Natta catalysts, and are interesting for modeling catalytic properties. Similar comportment has been observed with diamine bis (phenolate) ligands. ... 

The most thoroughly studied class of phenoxyl radical complexes was prepared by oxidation of first-row transition metal complexes of the type of macrocyclic phenolate ligands shown in Figure 4. Studies of those compounds that contain Ga , Sc , and have been particularly useful for differentiating and establishing the properties of coordinated vs. uncoordinated phenoxyl radicals. Due to their closed shell nature, these ions are both spectroscopically silent and redox inactive, thus enabling the properties of phenoxyl radicals in their complexes to be seen unmasked from those of the metal ion. Data for oxidized forms of the complexes [L M] ((l)-(4) are illustrative). These compounds undergo three reversible one-electron oxidations at approximately equally spaced... 

Several years ago, Kol and coworkers began investigating the group 4 metal chemistry of amine bis(phenolate) ligands These ligands feature several useful properties, in particular (1) a broad... 

Figure 17 Acid-base switch process in second-generation Zn + calix complexes (a). The five-coordinate complex (1) yields the five-coordinate complex (2) upon deprotonation of its capping phenol ligand. (2) is in equilibrium with the guest-free four-coordinate complex (3). Excess base generates a four-coordinate complex (4) devoid of host-guest properties. Proposed mechanism for the peptidase activity of astacin and serralysin, in view of the acid-base switch process of the model (b)." ...

Mixed N,S,0 donor sets are useful to compare the coordination ability and the structural consequences of various donor sets and to induce a variety of structural properties. The solid-state structures of [Ni(pyzs)]BF4, [Ni(pyrs)]BF4 and [Ni(pyzo)]BF4 containing dissymetric tetradentate ligands with N2S2 (543) and N2SO (544) donor sets are square planar.1397 The phenolate-based complexes are essentially planar in nitromethane, but distorted octahedral in methanol, while thiophenolate-containing complexes remain square planar in both solvents. 

The synthesis of the N03 and PFg salts of the iron(III) complex of the terdentate phenolate anion of the liquid crystal Schiff base (7) provides the first example of the coexistence of spin transition and liquid crystal properties in a single compound. The ligand now needs to be tuned to increase the spin cross-over transition temperature and decrease the transition temperature to the liquid crystal state. ... 

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