Cobalt complexes intercalation

Anionic complexes can easily be prepared by the sulfonation of the aromatic rings in the complexes. Sulfonated cobalt phthalocyanine intercalated in a layered double hydroxide host was a stable catalyst for the oxidation of thiols162,163 and phenol derivatives.164 It was concluded that the complex has been intercalated with the plane of the phthalocyanine ring perpendicular to the sheet of the host (edge-on orientation) (Fig. 7.2). 

NC3H9, 1-Propanamine intercalate with HNbTiOj, 22 89 NC4H9, Propane, 2-isocyano-2-methyI-tungsten complex, 24 198 NC4H, 1-Butanamine intercalate with HNbTiOs, 22 89 NCsHs, Pyridine cobalt complexes, 23 73 intercalate with FeClO (1 4), 22 86... 

Other indicators, such as daunomycin or cobalt complexes, act as intercalators. The changes in the area or peak potential of the indicator oxidation process are used as anal d ical signal [22,23]. 

Figure 13-4. Co2p spectra of cobalt-phen complexes intercalated in a-zirconium phosphate compared with those of Co(OH) and [Co(phen) ]Cl ...

Figure 13-4. Co2p spectra of cobalt-phen complexes intercalated in a-zirconium...

The intercalation of polycyclic aromatic-substituted cobalt(III) sarcophaginates (Scheme 117) with DNA is discussed in Ref 315. The hydrophobic polycyclic aromatic groups bound to the hydrophilic cobalt(III) cages are effectively solubilized in water. The complexes, being cationic, should associate with the negatively charged phosphodiester backbone of DNA. 

Tris(phenanthroline) complexes of ruthenium(II), cobalt(III), and rhodium(III) are octahedral, substitutionally inert complexes, and as a result of this coordina-tive saturation the complexes bind to double-helical DNA through a mixture of noncovalent interactions. Tris(phenanthroline) metal complexes bind to the double helix both by intercalation in the major groove and through hydrophobic association in the minor groove. " " Intercalation and minor groove-binding are, in fact, the two most common modes of noncovalent association of small molecules with nucleic acids. In addition, as with other small molecules, a nonspecific electrostatic interaction between the cationic complexes and the DNA polyanion serves to stabilize association. Overall binding of the tris(phenanthroline) complexes to DNA is moderate (log K = 4)." ... 

In our first study, we reported on a method of clay intercalating cobalt phosphine complexes (e.g., CoCl2(PMePh2)2 and CoCl2(P PrPh2)2) which, in combina-... 

Immobilized cobalt(II) and zinc(II)phthalocyanine anchored on silica or intercalated in the galleries and cavities of layered double hydroxides (hydrotalcite) and NaX zeoMte catalyze or photocatalyze the oxidation of 2-mercaptoethanol and sodium thiosulfate. The activity of the immobilized catalysts for oxidation and photooxidation is lower than that of the complexes in homogeneous phase. This is due to the hindered diffusion of dioxygen and sulfur-containing compounds to the active catalyst sites. 

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