Purine-Functionalized Ferrocene Derivatives: Efficient Redox Catalysts for Oxidation of Methyl Blue and Reduction of Trinitrophenol

Abstract

Herein, we report a novel organometallic series of potent purine-functionalized ferrocene derivatives (PFD) as redox catalysts. The synthesized PFDs were characterized through FTIR, ^H/CNMR, and liquid chromatography–mass spectrometry (LCMS). Their thermogravimetric analysis (TGA) revealed the thermal stability up to 250 °C, and degradation was noted in the range of 300–500 °C. Their catalytic performance was tested and found for oxidative degradation of methyl blue (MB) up to 99% and reductive conversion of trinitrophenol (TNP) into triaminophenol (TAP) up to 92%, which is supported by their band gap analysis (2.7 eV). The highest unoccupied molecular orbital (HUMO) and lowest unoccupied molecular orbital (LUMO) calculations confirmed the stable geometry of PFDs, and negative values of HOMO and LUMO have supported the oxidation and reduction performance of PFDs as they were noted as Vb > Va > Vc > Vd > Ve due functions of variable substitution. The analysis of the Lagergren pseudo-first-order kinetic model, in support of catalytic performance, revealed that the mobility of dye/phenol molecules with the PFD is what regulates the catalytic conversion rate.