Cobalt polypyridyl complexes

In order to avoid these limitations, there is a need for alternative electrolytes which work in both n-type and p-type systems. One such class of species is the cobalt polypyridyl complexes such as Co tris(4,4"-di-ferf-butyl-2,2"-dipyridyl) perchlorate.Gibson et al. employed this redox couple in a NiO-based p-type device in conjunction with two perylene-based dyes, PI and PINDI (Figure 3.74). ... 

Barve A, Ghosh S, Kumbhar A, Kumbhar A, Puranik V. Synthesis, DNA-binding and photocleavage studies of cobalt(III) polypyridyl complexes. I Inorg Biochem 2003 96 100. 

Zhang QL, Liu JG, Liu JZ, et al. Effect of intramolecular hydrogen-bond on the DNA-binding and photocleavage properties of polypyridyl cobalt(III) complexes. Inorg Chim Acta 2002 339 34 10. 

Wang X-L, Chao H, Li H, et al. DNA interactions of cobalt(III) mixed-polypyridyl complexes containing asymmetric ligands. J Inorg Biochem 2004 98 1143-50. 

Both our photochemical and radiation studies have focused on the chemistry of very reactive species in aqueous solution. Indeed, it is because the photochemical work involved aqueous media that radiation chemistry techniques could be so useful to us. Our pulse radiolysis work has led to a number of highly unusual mechanistic conclusions. In the area of low-oxidation-state chemistry, several of the systems violate standard organometaUic dogma. We investigated the rate of hydride formation in another cobalt(I) system, that derived from the high-spin d polypyridyl-cobalt(I) complexes (28). Remarkably, electron transfer was found to be the rate-determining step for formation of the hydride complex, and contributions from Bronsted acid pathways contribute neghgibly to the rate. Rather, the hydride formation appears to involve H-atom transfer from the protonated bpy radical. The H-atom receptor may be either Co(bpy)2 or Co(bpy) as shown in Scheme II. 

Prasad R, Scaife DB (1977) Electro-oxidation and electro-reduction of some iron (II), cobalt(II) and nickel(n) polypyridyl complexes in acetonitrile. I Electroanal Chem 84 373-386... 

Even advanced structures with a hemimetallocene or dicarbonylhydrazine structure have been formed [204, 205]. End-group modification is also known (e.g., see Fig. 12) [116, 206, 207]. For cobalt complexes, dendrimers with polypyridyl end groups were prepared, whose solubility can be manipulated directly by electrochemical means [208]. 

Takada K, Storrier GD, Goldsmith JI, Abruna HD (2001) Electrochemical and adsorption properties of PAMAM dendrimers surface-functionalized with polypyridyl cobalt complexes. J Phys Chem B 105 2404—2411... 

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