The synthesis and redox-induced off–on PL properties of poly(3,4-bisphenyl-N-methylferrocene-pyrrole-2,5-dione)

A novel π-conjugated polymer containing a ferrocene group was designed and synthesized from 3,4-bis(4-bromophenyl)-N-methylferrocene-pyrrole-2,5-dione by dehalogenation polycondensation with the zerovalent nickel complexes (a Yamamoto reaction). The polymer was characterized by FT-IR, 1H NMR, gel permeation chromatography, UV, cyclic voltammetry and Fluorescence spectroscopy. The polymer has the Mw of 2620 and polydispersity index of 1.5. Also this polymer showed high solubility in common organic solvents, good film formability on the glass substrate and redox property. The fluorescence of the model compound and polymer with a diphenylmaleimide moiety is almost quenched due to the ferrocene group because of the intramolecular electron transfer. However, the model compound and the polymer showed a recovered fluorescence when a ferrocene group of them was oxidized chemically and electrochemically.