Transition metal complexes, polymers containing

Equation (7) has been studied in several articles and a summary is available in the literature [50,70], The mercury-cystine system is, however, more complex than what is implied in Eq. (7) and can, depending on the electrode potential, include adsorbed species such as (RS)2Hg and (RS)2Hg2 [70], The system has been studied and explored in detail [70], Cystine can also be reduced at carbon electrodes modified with conducting polymers containing fixed metal thiolate sites [50,71], different macrocyclic transition metal complexes (often containing cobalt and phtalocyanines or porphyrins) [50,55,57,72,73], or vitamin Bj2 [56], which lower the overpotential necessary for reduction. 

The polymer CgoPt has also been made by using Pt(l,5-cyclooctadiene)2 [88], Various CjoM polymer films have been prepared by electrochemical reduction of transition metal complexes of the central metal Pd(II), Pt(II), Ir(I), Rh(l), Rh(ll), Rh(lll) and Au(l) [89, 90]. The metal complex in solution is first electrochemicaUy reduced to the zerovalent metal, which then forms polymer films containing M Coo on the electrode. 

High- Tg Conjugated Polymers Containing Transition Metal Complexes... 

Figure 6 Schematic model showing the design concept of conjugated PR polymer containing transition metal complexes. (Reprinted from Ref. 77. Copyright 1996 American Institute of Physics.)...

Double helical DNA is a water-soluble polymer that contains an electronically well-coupled stack of aromatic heterocyclic base pairs. This review describes efforts in our laboratory to characterize electron-transfer reactions between transition metal complexes bound by intercalation within the 7r-stack of DNA. Much information is available concerning the structure, synthesis, and methods of characterization of this polymer. Also, research in our laboratories has been directed toward describing the photophysical and photochemical properties of metal complexes bound to DNA. Using these metal complexes to probe the DNA 7r-way, we are now in a position to ask Is DNA a molecular wire ... 

The optoelectronic properties of conjugated polymers containing the rhenium diimine unit [Re(CO)3(phen)Cl] have been studied. Charge-carrier mobility measurements showed that the presence of metal complexes could facilitate the charge-transport process, and the enhancement in carrier mobility was dependent on the metal content in the polymer. The use of transition metal complexes for both photovoltaic and electroluminescence applications was demonstrated. 

To obtain vinylsilanes from alkynes, transition metal complexes of Group VIII combined with a main group metal chloride are particularly effective." In the presence of a heterogeneous catalyst like Pd/y-alumina, Rh/carbon and polymer bound Pt, trichlorosilane gives trichlorovinylsilane with atmospheric pressure of acetylene." Platinum supported on sulfur-containing silica gel is a practical catalyst for 1,2-dihydrosilylation, as exemplified in equation (10). ... 

Summary The stepwise synthesis of the polycarbosilanes (Cl2SiCH2CH2) (5) and (H2SiCH2CH2)n (6) are described. On addition of catalytical amounts of transition metal complexes to polymer 6 dehydrogenation occurs and a further crosslinked carbosilane (8) is obtained by formation of new silicon-silicon bonds. Pyrolysis of carbosilane 8 produces a black ceramic material, containing P-SiC together with carbon. The ceramic yield after pyrolysis of 8 is approximately four times the yield obtained when 6 is employed as the starting material. From polymeric 8 preceramic fibers are accessible subsequent pyrolysis yields ceramic fibers. Moreover, the carbosilane 8 can be utilized as a binder for ceramic powders. 

The coordination of tricarbonylmaganese and pentamethylcyclopentadienylcobalt to poly(9-hexylfluorene) was examined (Scheme 2.60).274 Polymer 226 contained both 5- and 6-membered aromatic rings that can coordinate the transition metal complexes however, studies indicated that the coordination to the 5-membered ring was preferred. Reaction of 226 with MnBr(CO)5 yielded polymer 227 with a ratio of 1 1.5 for the complexed to the uncomplexed rings however, reaction of 226 with BuLi followed by (C5Me5)Co(acac) and then oxidation of the solution with HC1 gave polymer 228. Polymer 228 was determined to be a mixture of... 

Gagn6 et al. developed polymer active sites that additionally contained a receptor (recognition sites) displayed in the outer sphere of the metal center (reactive site). The Suzuki reaction of /)-bromoanisole with phenyl boronic acid and the allylation of dimethyl malonate with allyl acetate were both chosen to assess the presence and/or effect of the crown-ether in crown-ether-molecular imprinting polymer-palladium complex. The results showed that molecular imprinting can be used to functionalize the second-coordination sphere of a transition metal complex and subsequently affect its catalytic behavior. 

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