Ferrocene-functionalized hyperbranched polyphenylenes: Synthesis, redox activity, light refraction, transition-metal complexation, and precursors to magnetic ceramics

New catalyst systems for diyne polycyclotrimerization were developed, E-l-[2-(2,5-Diethynylphenyl)vinyl]ferrocene (1), a ferrocene-containing diyne, was polymerized by ruthenium- and rhodiumbased catalysts, affording hyperbranched polyphenylenes (hb-P1) with high molecular weights (M_w up to ∼1.4 x 10⁵) in high yields (up to 100%). Effects of reaction conditions on the polymerization process were investigated, and structures of the resultant polymers were characterized by spectroscopic methods. The polymers were soluble, thermally stable, and redox active. Complexation with cobalt carbonyls further metalized the polymers. Both the polymers and their cobalt complexes showed high refractive indices (RI up to ∼1.81) at 300-1700 nm, large Abbé numbers (v_D' up to ∼681), and low optical dispersions (D' down to ∼0.0015) in the telecommunication wavelength region. Pyrolyses of the polymers and their complexes furnished magnetic ceramics with high magnetizabilities (M_s up to ∼83 emu/g).