One-step photocatalytic benzene hydroxylation over iron (II) phthalocyanine: A new application for an old catalyst

In the present study, iron (II) phthalocyanine was introduced as an effective and recyclable photocatalyst for direct hydroxylation of benzene to phenol as a model reaction under photocatalytic conditions at ambient temperature. The effect of different parameters such as solvent, concentration of the oxidant, irradiation time, and amount of the catalyst was investigated. Acetonitrile was selected as the optimum solvent, where hydrogen peroxide plays the role of the oxidant which is considered as an eco-friendly process. The results not only showed a 15.2 % yield of phenol at a selectivity of higher than 99 % under optimized condition but also exhibited a highly stable and reusable behavior. The catalyst was thoroughly characterized by UV-vis spectroscopy, Fourier transform infrared spectroscopy (FT-IR), field emission electron microscopy (FE-SEM), high-resolution transmittance electron microscopy (HR-TEM), X-ray diffraction (XRD), nitrogen adsorption-desorption isotherm (BET), and X-ray photoelectron spectroscopy (XPS). Density-Functional Tight-Binding (DFTB+ ) calculation was used to study the catalyst transition energy on the Materials Studio software.