Cobaltocenium polymers

Like their isoelectronic ferrocene counterparts, cobaltocenium units are resistant to strong oxidizing agents and possess interesting electrochemical behavior. The synthesis of polyesters and polyamides containing cationic cobalt units in the main chain has been reported (32,74-76). Sheats and Carraher reported the synthesis of cobaltocenium polymers containing tin, antimony, titanium, and zirconium atoms in their backbone via the reaction of the dicarboxylic... 

CoCp unit C-C bond activation, 7, 80 CoCp unit CH activation, 7, 79 in ethylene polymerization, 7, 81 substituted ligands, 7, 71 synthetic applications, 7, 74 with )4-cyclobutadiene applications, 7, 66 new ligand preparation, 7, 70 with )4-(cyclobutadiene) ligands, 7, 59 dendrimeric cobaltocenium derivatives, 7, 88 with fullerenes, 7, 51 HP-NMR and HP-IR studies, 1, 488 with rj -hydrocarbyl units, 7, 8 immobilized, as polymer support, 12, 681 kinetic studies, 1, 520 with )3-ligands, 7, 56 with metallaboranes, 3, 158 overview, 7, 1-119... 

The synthesis of polymers containing main-chain cobaltocenium units has also been studied as this 18-electron organometallic moiety is isoelectronic with ferrocene. The synthesis of partially soluble polyesters (4.6, E = 0, R=(CH2)4, CH2C6H4CH2) was reported using solution condensation polymerization techniques, and the soluble fractions were of low molecular weight (M 2500-4000,... 

In the 1970s, Carraher reported the synthesis of a number of cobaltocenium based polymers. Titanium, zirconium, and hafiiium polyesters were synthesized via reaction of the dicyclopentadienyhnetal dichloride complexes with disodium dicarboxylates of cobaltocenium in either aqueous or organic solvents. For example, the synthesis of a polymer (135) that contains cobaltocene and titanocene units in the backbone is shown in Scheme 35. ... 

The morphology of ferrocene-containing polymers has been examined in some detail. In the block copolymer of poly(ferrocenyldimethylsilane-b-dimethyl-siloxane) (PFDMS-b-PDMS) with a 1 6 block ratio long rodlike micelles are observed rather than spherical structures in a variety of PDMS-selective n-alkane solvents when the solutions are prepared at or near ambient temperature. The reasons for these observations are subsequently discussed in detail. A further series of mixed ferrocene cobaltocenium dendrimers have been obtained these have been prepared in the reaction of the acyl chlorides of ferrocene and the cobaltocenium PF " with polypropylene dendrimers. ... 

Fig. 9 Cobaltocenium-containing polymers obtained by atom transfer radical polymerization (ATRP) (reprinted with permission from [179]. Copyright 2012 American Chemical Society)...

Ren L, Zhang J, Hardy CG, Doxie D, Fleming B, Tang C (2012) Preparation of cobaltocenium-labeled polymers by atom transfer radical polymerizati(Hi. Macrranolecules 45 2267-2275... 

Zhang J, Ren L, Hardy CG, Tang C (2012) Cobaltocenium-ctmtaining methacrylate homopolymers, block copolymers, and heterobimetallic polymers via RAFT polymeiizatioiL Macromolecules 45 6857-6863... 

Wei, J.J., Ren, L.X., Tang, C.B., Su, Z.H., 2014. Electric-stimulus-responsive multilayer films based on a cobaltocenium-containing polymer. Polym. Chem. 5 (22), 6480-6488. 

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