Metal-oxygen-polymer complex

Particularly, the formation of new chemical bonds at a metal-polymer interface has recently gained a lot of attention, thanks to development of surface analytical tools. In this connection, photoemission spectroscopies (XPS, UPS) have been extensively used. The adhesion is related to bond formation between the metal atom and the functional groups at the polymer surface. The presence of oxygen containing groups is found to lead to the formation of metal-oxygen-polymer complexes and to increase the adhesion. ... 

The existence of these metal-oxygen-carbon complexes can account for many of the observed changes already discussed. We expect the metal to be more tightly banded to the polymer (polyvinyl alcohol) through such a complex than if one was not present,... 

Co(H)- and Fe(II)chlorophyllins (8) with partly quarternized poly(4-vinylpyridine)45 In aqueous solution at pH 10 the metal ions are easily oxidized. Fundamentally the rate of irreversible oxygenation is 1010 times slower for the polymer complex than with pyridine. 

Various oxidations with [bis(acyloxy)iodo]arenes are also effectively catalyzed by transition metal salts and complexes [726]. (Diacetoxyiodo)benzene is occasionally used instead of iodosylbenzene as the terminal oxidant in biomimetic oxygenations catalyzed by metalloporphyrins and other transition metal complexes [727-729]. Primary and secondary alcohols can be selectively oxidized to the corresponding carbonyl compounds by PhI(OAc)2 in the presence of transition metal catalysts, such as RuCls [730-732], Ru(Pybox)(Pydic) complex [733], polymer-micelle incarcerated ruthenium catalysts [734], chiral-Mn(salen)-complexes [735,736], Mn(TPP)CN/Im catalytic system [737] and (salen)Cr(III) complexes [738]. The epox-idation of alkenes, such as stilbenes, indene and 1-methylcyclohexene, using (diacetoxyiodo)benzene in the presence of chiral binaphthyl ruthenium(III) catalysts (5 mol%) has also been reported however, the enantioselectivity of this reaction was low (4% ee) [739]. 

Small-molecule transport other than olefin and molecular oxygen facilitated transport through a metal-polymer complex containing carriers (silver ions and metalloporphyrins, respectively) has also received attention, such as nitrogen transport by a cyclopentadienylmanganese and benzenechromium complex attached to a polymer [50,51], and CO2 and H2S transport based on ion-... 

In addition, as mentioned above, the polymer-supported complexes possess the bidentate carboxylate group, and the metal-oxygen bonds in these complexes are rich in covalency. For Ziegler-Natta catalysts, one of the requirements for the formation of the active center is the alkylation of the metal ions by exchange between the alkyl group in alkyl aluminum and carboxylate. The covalency of the metal-oxygen bond in the support complex makes this exchange reaction easier. 

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