Poly terpyridine

Several approaches have been undertaken to construct redox active polymermodified electrodes containing such rhodium complexes as mediators. Beley [70] and Cosnier [71] used the electropolymerization of pyrrole-linked rhodium complexes for their fixation at the electrode surface. An effective system for the formation of 1,4-NADH from NAD+ applied a poly-Rh(terpy-py)2 + (terpy = terpyridine py = pyrrole) modified reticulated vitreous carbon electrode [70]. In the presence of liver alcohol dehydrogenase as production enzyme, cyclohexanone was transformed to cyclohexanol with a turnover number of 113 in 31 h. However, the current efficiency was rather small. The films which are obtained by electropolymerization of the pyrrole-linked rhodium complexes do not swell. Therefore, the reaction between the substrate, for example NAD+, and the reduced redox catalyst mostly takes place at the film/solution interface. To obtain a water-swellable film, which allows the easy penetration of the substrate into the film and thus renders the reaction layer larger, we used a different approach. Water-soluble copolymers of substituted vinylbipyridine rhodium complexes with N-vinylpyrrolidone, like 11 and 12, were synthesized chemically and then fixed to the surface of a graphite electrode by /-irradiation. The polymer films obtained swell very well in aqueous... 

Briefly, norbornene-derivatized silica was first reacted with Mo(N-2,6-i-Pr2-C6H3)(CHCMe2Ph)(OCMe(CF3)2)2, followed by (4 -(norbom-2-en-5-ylmethylen-oxy)terpyridine). Loading with Cu (I) afforded the desired ATRP support [18, 22-24], Typical metal loadings were in the range of 15 mmolg. Polystyrene (PS) obtained with these supports under ATRP-conditions showed comparably low poly-dispersities (PDI = 1.55-1.77). The ATRP system consisted of a metal center with one terpyridyl and presumably three acetonitrile ligands, which were at least in part substituted by monomer. Consequently, in contrast to standard systems [25], the equilibrium in this type of reaction did not require conformational... 

Meier MAR, Schubert US. Terpyridine-modified poly(vinyl chloride) possibilities for supramolecular grafting and crosslinking. J Polym Sci Part A Polym Chem 2003 41 2964-2973. 

Lohmeijer BGG, Schubert US. Water-soluble building blocks for terpyridine-containing supra-molecular polymers synthesis, complexation, and pH stability studies of poly(ethylene oxide) moieties. Macromol Chem Phys 2003 204 1072-1078. 

Several approaches have been undertaken to construct redox-active polymermodi-fied electrodes containing such rhodium complexes as mediators. Beley [66] and Cosnier [67] used the electropolymerization of pyrrole-linked rhodium complexes for their fixation at the electrode surface. An effective system for the formation of 1,4-NADH from NAD applied a poly-Rh(terpy-py) (terpy = terpyridine py = pyrrole) modified reticulated... 

Finally, conjugated materials 40 based on poly(phenylene thiophene) and poly (fluorene thiophene) main chain polymers functionalized with pendant trithiocyanato ruthenium terpyridine complexes were synthesized by the Suzuki coupling reaction. Heterojunction photovoltaic cells with the simple structure ITO/polymer/C-60/Al were fabricated. Under simulated AM1.5 solar light illumination, the short circuit currents, open circuit voltages, and power conversion efficiencies of the photovoltaic cells were measured to be 1.53-2.58 mAcm 2, 0.12-0.24 V, and 0.084-0.12%, respectively [77]. 

An ingenious way to create poly(phenylene) polymers with metals in the backbone is to use a coordination polymer strategy in which an oligophenylene substituted at each end by a terpyridine ligand can react with a metal center to yield a polymer. An... 

Controlled/ Living radical polymerization (CRP) of vinyl acetate (VAc) via nitroxide-mediated polymerization (NMP), organocobalt-mediated polymerization, iodine degenerative transfer polymerization (DT), reversible radical addition-fragmentation chain transfer polymerization (RAFT), and atom transfer radical polymerization (ATRP) is summarized and compared with the ATRP of VAc catalyzed by copper halide/2,2 6 ,2 -terpyridine. The new copper catalyst provides the first example of ATRP of VAc with clear mechanism and the facile synthesis of poly(vinyl acetate) and its block copolymers. 

Scheme 2 Popular metal complexation motifs used for supramolecular polymer-network formation. py pyridine, bpy bipyridine, tpy terpyridine, BTP 2,6-bis(l,2,3-triazol-4-yl)pyridine, BIP 2,6-bis(l-methylbenzimidazolyl)pyridine, DOPA dihydroxy-phenylalanine, PAA poly (acrylic acid)...

Post-polymerization functionalization has also been applied to the synthesis of terpyridine-modified polymers [ 126]. In a recent approach, Schubert and colleagues employed this method to prepare poly(pentafluorostyrene) with terpyridines in the side chains [127]. First, poly(pentafluorostyrene) with a narrow polydispersity index of just 1.08 was synthesized by nitroxide-mediated polymerization. In a second step, this polymer was converted with amine-functionalized terpyridine under microwave heating, selectively substituting the para-fluorines. Addition of iron(II) sulfate to a solution of the terpyridine-functionalized polymer in a mixture of chloroform and methanol leads to gelation at a polymer concentration of 33 g In another work, Schubert and coworkers prepared metal-cross-Iinked polymer networks from linear and tri-arm PEG precursors, both functionalized with terpyridine at their OH-termini [128]. Quantitative functionalization of these precursors was achieved by conversion of the hydroxy-functionalized PEG derivatives with 4-chloro-2,2 6, 2"-terpyridine under basic conditions. However, quantitative cross-linking with iron(II) chloride was not observed in methanol solutions, neither at room temperature nor at elevated temperature, but only a small quantity of cross-linked material precipitated from the solution. This observation was attributed to a strong tendency of the tri-arm PEG to form intramolecular complexes, acting as a chain stopper rather than as a cross-linker. 

The monomeric unit used in the studies in shown in Fig. 45.3. It is based on poly(s-caprolactone) with a terpyridine ligand (for metal complexation) at one end and an ureido-pyrimidone group (for hydrogen bonding) on the other end. The polymeric spacer is used to control the solubility in various solvents, in such a way that both hydrogen-bonding and metal-complexation can take place simultaneously. This unit shows a good solubility in chloroform. 

Landsmann, S. Winter, A. Cbiper, M. Fuston, C.-A. Hoeppener, S. Wouters, D. Gohy, J.-F. Scbubert, U. S., Poly(dimeth siloxane)-Substituted 2,2 6,2 -Terpyridines Synthesis and Characterization of New Amphiphihc Supramolecvdar Dihlock Copolymers. Macromol. Chem. Phys. 2008,209, 1666-1672. 

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