New ethylferrocenyl based pyranylidene bridge dyads: Synthesis, characterization and investigation of electrochemical and optical properties

Abstract

In this research, we designed and synthesized six new pyranylidene backbone end-capped with donor and acceptor groups. Ethylferrocene was presented as new donor to evaluate the effect of alkyl chain substituted in ferrocene unit on linear optical and electrochemical properties of push-pull systems and compare it with their unsubstituted ferrocene analogues. Proposed structures were confirmed via FT-IR, 1H NMR, 13C NMR, elemental analyses and mass spectra. Optical band gaps were determined in the range of 1.85–2.24 using UV–vis spectroscopy for synthesized chromophores. Electrochemical studies were performed by cyclic voltammetry and show the reversible redox behavior with ΔEp=Epa−Epc≤0.08V, and diffusion limited for the redox process.