Schiff-base chelates, cobalt

Mercury, like zinc, appears in some chain-like structures, but apparently only in combination with other metals such as As, Sb, Nb, and Ta. Some of these have the characteristics of metallic conductors.15 Rather high molecular weights have been obtained in the preparation of 6-coordinate cobalt (III) chelate polymers with acetylacetonato and leucinato ligands, 7-coordinate dioxouranium-(VI) dicarboxylate polymers, and 8-coordinate zirconium (IV) polymers with Schiff-base ligands.77... 

The story of metal complexes able to bind Oj reversibly begins with the discovery in 1938 that certain 0,N-chelates (Schiff bases) of cobalt(II) are oxygen carriers, to be joined in 1963 by Ir(PPh3)2(CO)(Cl) which reversibly adds O2 . Other low valent Pt... 

The oxidation of Ti " by Fe" and the reaction between TF" and Sn" have been studied using flow and potential-time dependences. An investigation has also been made of the Ag -Ce " reaction. Polarographic studies of planar Schiff base complexes of Co , Ni", and Cu have shown well-defined oxidation waves and in some chelates the two-electron oxidation Co" Co " is postulated. Kinetic studies have also been made on the oxidation of cobalt(ii) dipyridyl complexes by copper(n) and iron(m) perchlorates in anhydrous acetonitrile. Solvent effects have also been investigated in redox reactions of tetrahalogenoplatinum(iv) complexes of the type PtLaX4. ... 

Oxygenation of styrene with asymmetric induction can be observed with this process in the presence of optically active cobalt(II) Schiff base chelates [195,196]. 

Polymer cobalt (II) Schiff base chelates based on the radical copolymerization of 4,4 -divinylsalens with styrene or 4-vinylpyridine are described [208-210]. One example of a polymer employing 2-hydroxy-5-vinylbenzaldehyde and 1,2-diaminoethane is shown in 46. The Co(II) chelates were investigated for their activity in the binding of oxygen and its... 

Historically, cobalt catalysts were the first catalysts to be used in chelation-assisted C—H bond functionalization. The first report by MurahashF in 1955, involved the ort/to-carbonylation of a Schiff base 1 using dicobalt octacarbonyl to give the isoin-... 

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