Strained 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... 

Thermal ROP of silicon-bridged [1 Jferrocenophanes Thermal ROP of other strained metallocenophanes Living anionic ROP of strained metallocenophanes Transition metal-catalyzed ROP of strained metallocenophanes Other ROP methods for strained metallocenophanes Properties of polyferrocenylsilanes... 

The thermal ROP methodology established for silicon-bridged [I]ferrocenophanes has been extended to many other strained metallocenophanes, which allows access to high molecular weight polyferrocenes with different spacer groups. As discussed later (see Section 12.06.3.3.6), this permits modification of the properties of the polymer, such as the extent of the metal-metal interactions. 

ROP reactions generally occur by a chain-growth mechanism (Chapter 1, Section 1.5.2.2.3) and therefore represent a particularly desirable route for the preparation of high molecular weight polyferrocenes. As is clear from the polymers described so far in Sections 3.1 and 3.2, such materials are rare if the ferrocene groups are in close proximity to one another so as to permit substantial metal-metal interactions. The first syntheses of polymetallocenes by ROP methods were reported in early 1992. A novel atom-abstraction-induced ROP process for [3]trithiaferroce-nophanes was described early in that year and these results are discussed in Section 3.5 [60]. Thermal ROP of strained metallocenophanes, which is discussed in this section, was reported a few months thereafter [61]. 

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-... 

A very convenient, transition metal-catalyzed ROP route to polymetallocenes from strained metallocenophanes was reported in 1995 [87, 88]. Various Rh , Pd", Pd ,... 

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

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