Structural, spectroscopical, electronic, non-linear optical characterization and antioxidant activity of 2-hidroxychalcones para-derivatives: An experimental and theoretical approach

Abstract

The molecular structures of the chalcones were synthesized because of the crescent interest in the chemistry of chalcones, whose properties demonstrate a wide range of applications. This work aims to characterize the structural, spectroscopic, and electronic properties and propose the reaction mechanism for the antioxidant activity of the four chalcone derivatives. The results for the structural characterization showed that the experimental and theoretical data for the RMN (1H and 13C) and the Infrared are in excellent agreement. Furthermore, the nonlinear optical properties demonstrated that chalcones (1) and (4) had a higher NLO character. Hence, these chalcones can be used in optoelectronic devices due to their enhanced non-linear optical properties. The electronic properties of the four chalcones were fully characterized by the FMO, QCRD, Fukui functions, and the MEP: chalcone (1) showed a higher nucleophilic character, chalcones (2) and (3) a higher electrophilic character, and chalcone (4) demonstrated to have a balance between the nucleophilic and electrophilic character. Finally, the antioxidant assays exhibited that all four chalcones are weak antioxidants and the mechanism thermodynamically favorable is the Hydrogen Atom Transfer (HAT) with the phenolic hydroxyl target for chalcones (2) - (4) and the methyl from the dimethylamine group for chalcone (1).