Ferrocene-based hyperbranched poly(phenyltriazolylcarboxylate)s: synthesis by phenylpropiolate-azide polycycloaddition and use as precursors to nanostructured magnetoceramics

Developing new polymerization methodologies for the construction of ferrocene-based hyperbranched polymers is an important research topic and a challenging task. In this work, four ferrocene-based hyperbranched poly(phenyltriazolylcarboxylate)s (hb-PPTCs) with satisfactory molecular weights are facilely synthesized by the catalyst-free polycycloadditions of tris(3-phenylpropiolate)s (1a and 1b) and ferrocene-containing diazides (2a and 2b) in dimethylformamide at 100 °C in high yields. The obtained hb-PPTCs are soluble in common organic solvents. Thanks to the contained ferrocene units, the hb-PPTCs are electrochemically active. The resultant polymers can be used as precursors to yield nanostructured magnetoceramics with high magnetizabilities (M_s up to 90.9 emu g⁻¹) by pyrolysis at high temperature.