Phosphonylated p-aminophenol derivatives: Microwave Assisted Synthesis, Density Functional Theory study and biological activities evaluation

Abstract

A series of three α-aminomethylphosphonates have been synthesized in excellent yields, via Kabachnik-Fields reaction, under different conditions, at reflux heating and under microwave irradiations, by condensation of 4-aminophnol, trimethylphosphite and various aromatic aldehydes. The structures of the obtained compounds were confirmed by Elemental analysis, UV-vis, FT-IR, 1H-NMR and 31P-NMR spectra. Then, we present a detailed DFT study, based on B3LYP/6-31G(d,p) level of theory, of geometrical structures, vibrational, electronic properties of these compounds in order to make comparative study between these molecules. The Density Functional Theory method was beneficially used to analyze the HOMO-LUMO molecular orbitals and to calculate the energy gap (∆E), Ionization potential (IP), Electron Affinity (EA), Global Hardness (η), Chemical Potential (μ) and Global Electrophilicity (ω). The title compounds were screened for their antibacterial activity. All the title compounds exhibited promising antibacterial activity.