Transition Metal-Catalyzed Ring-Opening Polymerization of Silicon-Bridged [1]Ferrocenophanes in the Presence of Functional Silanes: Molecular Weight Control and Synthesis of Telechelic Poly(ferrocenylsilanes)

✍ Scribed by Alexandra Bartole-Scott; Rui Resendes; Ian Manners

• Publisher: John Wiley and Sons
• Year: 2003
• Tongue: English
• Weight: 162 KB
• Volume: 204
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.200390094

✦ Synopsis

Abstract

The transition metal‐catalyzed ring‐opening polymerization of dimethyl[1]silaferrocenophane (fcSiMe~2~) (1), fc = Fe(η‐C~5~H~4~)~2~), in the presence of MePhSiH~2~, or the chlorosilanes ClMe~2~SiH, ClMePhSiH, or ClPh~2~SiH has been shown to allow access to poly(ferrocenylsilane)s R^1^R^2^R^3^Si[fcSiMe~2~]~n~H (4, 6–8), and R^1^[Me~2~Sifc]~m~SiR^2^R^3^[fcSiMe~2~]~n~H (5) with controlled molecular weights and which are capped by the corresponding R^1^R^2^R^3^Si and SiH groups (4, 5: R^1^ = H, R^2^ = Me, R^3^ = Ph, 6: R^1^ = Cl, R^2^ = R^3^ = Me, 7: R^1^ = Cl, R^2^ = Me, R^3^ = Ph, 8: R^1^ = Cl, R^2^ = R^3^ = Ph). Materials with molecular weights in the range M~n~ of 3.5 × 10^3^ to 2.5 × 10^4^ and polydispersities of 1.3–2.2 were prepared. All of the silanes examined in this study were found to be more reactive as capping agents than the previously studied Et~3~SiH; the order of reactivity for molecular weight control was determined to be MePhSiH~2~ ≈ ClMe~2~SiH ≈ ClMePhSiH ≈ ClPh~2~SiH > Et~3~SiH. In addition, the reactivity of the resulting SiCl end‐functionalities of poly(ferrocenylsilane)s 6 and 7 was explored, and reactions with commercial poly(ethylene glycol) methyl ether yielded poly(ethylene oxide)–block–poly(ferrocenylsilane) diblock copolymers, 10 and 11. The SiH end group, however, was much less reactive and attempts to utilize this functionality for hydrosilylation of divinyl‐terminated poly(dimethylsiloxane) to form block copolymers was ineffective.
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