Ruthenium complex polymers

Polyfluorene with on-chain ruthenium complex (polymer 49) has been synthesized by Suzuki polycondensation [77]. The photoluminescence of the copolymer was slightly blue-shifted as the concentration of dipyridy-lamine increased. The introduction of dipyridylamine and the ruthenium complex into the polymer significantly improved the photoluminescence efficiency. 

More polar functional groups such as ketones are hydrogenated effectively with homogeneous cationic rhodium and ruthenium complexes. Polymer catalysts active for both olefin and ketone hydrogenation activity were synthesized from ionic precursors such as Rh(norbornadiene)(acac) + HCIO4 or Rh(norbornadiene)(PE 3)2 + C104. Two types of coordination were observed, depending on the method of attachment " ... 

Novel Near-IR Electrochromic Ruthenium Complex Polymers... 

Subsequent to isolation of the polymer, the metallization could be conducted in a similar manner as that of the complexes reported elsewhere for DCH-Ru complexes (27-28). The ruthenium complex polymers, shown in Figure 2, thus made would be expected to exhibit similar electrochromic properties as the dinuclear ruthenium complexes while possessing the film forming characteristics of the parent polymer. We report herein the synthesis and characterization of these polymers. 

Thermal analysis was performed for ligand polymers 1-4 and ruthenium complex polymers 5-8. The ligand polymers were found to be less thermally stable (100-150 C) than the ruthenium complex polymers (>200 °C), except for polymer 4 (251 °C) vs. polymer 8 (209 °C), as assessed by thermogravimetry for 5% weight loss in nitrogen. Studies by Frazer e( al (36), revealed that aliphatic polyhydrazines undergo dehydration above 150 °C to... 

Electrochemistry was performed on ruthenium complex polymers as films on a Pt disk electrode. The cyclic voltammograms showed two quasi-reversible couples attributable to the two one-electron couples per dinuclear DCH-Ru fragment in the polymer. The results are listed in Table I. 

Lu Y (2010) Preparation of novel polypyridyl ruthenium complex polymers with high sensitivity for electrogenerated chemiluminescence via copolymerization. Photochem Photobiol Sci 9 392-397... 

Cj Hydroformation of CO with high-molecular weight olefins on either a cobalt or ruthenium complex bound to polymers. 

Yonemura, H., Yamamoto, Y. and Yamada, S. (2008) Photoelectrochemical reactions of electrodes modified with composites between conjugated polymer or ruthenium complex and single-walled carbon nanotube. Thin Solid Films, 516, 2620-2625. 

Nitration of the surface of polypyrrole and the subsequent reduction of the nitrate groups has been reported [244] and Bidan et al. [306, 307] have investigated the electrochemistry of a number of polymers based on pyrroles with /V-substituents which are themselves electrochemically active. Polypyrrole has also been successfully deposited onto polymeric films of ruthenium complexes [387], and has been used as an electrode for the deposition and stripping of mercury [388], As with most conducting polymers, several papers have also appeared on the use of polypyrrole in battery systems (e.g. [327, 389] and Ref. therein). 

Furthermore, the utilization of preformed films of polypyrrole functionalized by suitable monomeric ruthenium complexes allows the circumvention of problems due to the moderate stability of these complexes to aerial oxidation when free in solution. A similar CO/HCOO-selectivity with regards to the substitution of the V-pyrrole-bpy ligand by an electron-with-drawing group is retained in those composite materials.98 The related osmium-based redox-active polymer [Os°(bpy)(CO)2] was prepared, and is also an excellent electrocatalyst for the reduction of C02 in aqueous media.99 However, the selectivity toward CO vs. HCOO- production is lower. 

Hartmann P., Photochemically induced energy-transfer effects on the decay times of ruthenium complexes in polymers, Anal. Chem. 2000, 72(13) 2828-2834. 

They found almost complete quenching of the emission from the ruthenium complex and in addition the covalently linked compound considerably enhanced electron transfer to relay systems of aligned viologen units on micelles and polymers. 

Fig. 11. Gibson and coworkers synthesis of a polymer displaying the nucleobase thymine using ROMP initiated by Grubbs ruthenium complex... 

For the synthesis of carbohydrate-substituted block copolymers, it might be expected that the addition of acid to the polymerization reactions would result in a rate increase. Indeed, the ROMP of saccharide-modified monomers, when conducted in the presence of para-toluene sulfonic acid under emulsion conditions, successfully yielded block copolymers [52]. A key to the success of these reactions was the isolation of the initiated species, which resulted in its separation from the dissociated phosphine. The initiated ruthenium complex was isolated by starting the polymerization in acidic organic solution, from which the reactive species precipitated. The solvent was removed, and the reactive species was washed with additional degassed solvent. The polymerization was completed under emulsion conditions (in water and DTAB), and additional blocks were generated by the sequential addition of the different monomers. This method of polymerization was successful for both the mannose/galactose polymer and for the mannose polymer with the intervening diol sequence (Fig. 16A,B). 

The SULPHOS-containing rhodium and ruthenium complexes retained their catalytic activity in heteroarene hydrogenation when supported on styrene-divinylbenzene polymer [180] or on silica [181], and showed even higher activity than in homogeneous solution. This effect is attributed to the diminished possibility of dimerization of the active catalytic species to an inactive dimer on the surface of the support relative to the solution phase. The strong hydrogen bonds between the surface OH-groups on silica and the -SO3 substituent in 31 withheld the catalyst in the solid phase despite the rather drastic conditions (100 °C, 30 bar H2). 

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