Ring strain, metallocenophanes

Ring-opening polymerization of strained metallocenophanes, mainly ferroceno-phanes with Si atom at the bridge, to give high-molecular-weight poly-(metallocenes) 99PAC1471. 

Living anionic ring-opening polymerization, strained metallocenophanes, 12, 326 Living polymerization acetylenes... 

The first examples of the use of ROP of strained metallocenophanes to prepare high molecular weight polymetallocenes (Mn>10 ) involved silicon-bridged [Ijferrocenophane monomers 3.21 [61]. Specifically, polyferrocenylsilanes (PFSs) 3.22 (R,R = Me or Ph) were prepared by the thermal ROP of strained, ring-tilted silicon-bridged [l]ferrocenophanes 3.21 (R,R = Me or Ph) in the melt, at 130-... 

Ring-Opening Polymerization (ROP) of Strained Metallocenophanes 99 3 Electron Beam... 

I. Manners, Ring-opening polymerization of strained metallocenophanes a new route to high molecular weight poly(metallocenes), Pure Appl. Chem., 71, 1471-1476 (1999). 

Since the discovery of the ring-opening polymerization of strained metallocenophanes, a diverse series of metal-containing macromolecules have been synthesized and characterized (see Scheme 4). These include the following variations substituents on silicon, munber and type of bridging atoms, and substituents on the cyclopentadienyl rings. ... 

Ring-Opening Polymerization of Strained, Ring-Tilted Metallocenophanes New Route to Polymers Based on Transition Metals... 

To prepare [2]metallocenophanes that are even more strained than [2]ferrocenophanes 30, species with a larger ruthenium atom in the place of iron have been synthesized (81). Such [2]ruthocenophanes would be expected to possess much greater ring-tilt angles moreover, because ruthenocene is known to possess significantly different electrical properties compared to ferrocene, modified polymer properties would be anticipated (57). 

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