Ruthenium metallopolymers

Brennan JL, Keyes TE, Forster RJ (2011) Electrochemical properties of ruthenium metallopolymer monolayer-protected gold cluster nanocomposites. J Electroanal Chem 662(l) 30-35... 

Venkatanarayanan A, O Connell B, Devadoss A, Keyes TE, Forster RJ (2011) Potential modulated electrochemiluminescence of ruthenium metallopolymer films. Electrochem Commun 13(5) 396-398... 

B Ruthenium metallopolymer based on ruthenium bis-bipyridine and polyvinylimidazole [52],... 

The analogous osmium polymers have also been studied in great detail. The synthetic procedures required for these metallopolymers are the same as those described above for ruthenium however, the reaction times are longer. The similarity between the analogous mononuclear and polymeric species is further illustrated by the fact that the corresponding osmium polymers have considerably lower redox potentials and are also photostable, as expected on the basis of the behavior observed for osmium polypyridyl complexes. 

Forster, R.J. and Vos, J.G. (1990) Synthesis, characterization, and properties of a series of osmium-containing and ruthenium-containing metallopolymers. Macromolecules, 23 (20), 4372-4377. 

Platinum polyynes represent one of the most interesting and well-studied classes of linear metallopolymers. Dendritic analogs of these materials have been prepared via a variety of methodologies. One example is the nonametallic dendrimer 248 that was prepared via a convergent route as illustrated in Equation (92). Dendrimers based on ruthenium polyyne architectures have also been prepared and promising NLO properties have been identified. ... 

The synthesis of metallopolymers containing ruthenium and/or osmium compounds by covalent attachment of the metal centers to a polymer backbone is based on the different lability of the chloride ions in the complex cis-[M(bipy)2Cl2]. Removal of the first chloride ion occurs readily by refluxing in a low boiling point alcohol, such as methanol or ethanol. Removal of the second chloride requires aqueous solvent mixtures and/or higher temperatures. Consequently for the synthesis of metallopolymers of the type [M(bipy)2(POL)nCl]Cl, heating at reflux in ethanol is sufficient, whereas for the bis-substituted materials, i.e., [M(bipy)2... 

In Chapter 8, coauthored by Kelly and Vos, the electrochemical behavior of osmium and ruthenium poly(pyridyl) redox polymers is discussed in some detail. Vos has made significant contributions in this area. This chapter ties in well with the more general discussion presented by Lyons in Chapters 1 and 2, in that many of theoretical concepts addressed in the latter chapters are again discussed by Kelly and Vos with specific reference to redox-active metallopolymer materials. 

Dennany L, Hogan CF, Keyes TE, Forster RJ (2006) Effect of surface immobilization on the electrochemiluminescence of ruthenium-containing metallopolymers. Anal Chem 78(5) 1412-1417. doi 10.1021/ac0513919... 

Oxidative Eiectropoiymerization of Poiypyridyi Compiexes. Oxidative electropolymerization of suitably substituted [M (bipy)3l + complexes offers an alternative approach to the preparation of electrochromic redox active polymer films. Oxidative eiectropoiymerization has been described for iron(II) and ruthenium(II) complexes containing amino-substituted (31) and pendant aniline-substituted (32) 2,2 -bipyridyl ligands, and amino- and hydroxy-substituted 2,2 6, 2"-terpyridinyl ligands (33) [ligand structures (4) and (5)]. Analysis of IR spectra suggests that the eiectropoiymerization of [Ru(L )2l + [L = (4)], via the pendant aminophenyl substituent, proceeds by a reaction mechanism similar to that of aniline (33). The resulting metallopolymer film reversibly switches from purple to pale pink on oxidation of Fe(II) to Fe(III). For polymeric films formed from [Ru(L )2l + [L = (5)], via polymerization of the pendant hydroxyphenyl group, the color switch is from brown to dark yellow (see Electropolymerization). 

Polymers containing benzimidazole units in their backbones have also been used in the synthesis of coordination metallopolymers (159-162). Osmium and ruthenium coordinated polymers with bipyridine ligands have been prepared (159,160). These polymers (72, 73) possessed metal-metal interactions through their conjugated backbones. Communication between the ruthenium centers of 72 increased by deprotonating the imidazole protons (160). The osmium coordinated polymer (73) showed two reduction waves separated by 0.32 V, indicative of strong cnmmimication between the Os centers (159). 

O Reilly EJ, Dennany L, Griffith D, Moser F, Keyes TE, Forster RJ (2011) Ground and excited state communication within a ruthenium containing benzimidazole metallopolymer. Phys Chem Chem Phys 13(15) 7095-7101... 

Furthermore, the supply of thermal energy could also be used to influence the properties of a metallopolymer and to yield the desired effects. For this purpose, Zhou and coworkers utilized phase-separated ruthenium-containing polymers with two glass transition temperatures [71]. The transitions induced the a kind of mobility that is required for the self-healing process [72]. 

Beginning in 1949, Cassidy and coworkers presented a series of papers demonstrating redox polymers [46 9]. In these early demonstrations, the redox sites were based on hydroquinones. If the redox site is a transition metal complex, however, the redox polymer is also a metallopolymer [50-53]. Ruthenium and osmium metal-lopolymers with polyvinyfimidazole backbones, for example, are shown in panels B and C of Table 9.1. By participating in oxidation-reduction reactions with other species and through self-exchange, a redox polymer in solution can conduct electrons... 

C Osmium bis-bipyridine-based analog to the metallopolymer in panel B. Whereas ruthenium undergoes photochemistry, osmium does not [52]. 

Venkatanarayanan A, Spehar-Deleze A-M, Dennany L, Pellegrin Y, Keyes TE, Forster RJ (2008) Ruthenium aminophenanthroline metallopolymer films electropolymerized from an ionic liquid deposition and electrochemical and photonic properties. Langmuir 24 11233-11238... 

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