Spectroscopic and quantum mechanical studies of 4,6-dimethyl-2-hydroxy pyrimidine by density functional method

The electronic characteristics and molecular structure of 4,6-dimethyl-2-hydroxy pyrimidine were examined using theoretical and experimental methods. Density functional theory (DFT) at the B3LYP/6-31G(d, p) level was used to determine the optimized molecular geometry and vibrational frequencies, which were then compared to the observed FT-IR spectra. The theoretical and experimental vibrational frequencies were found to be in good agreement. The HOMO and LUMO energies were − 8.96 and − 4.46 eV, respectively, with an energy gap of 4.50 eV, according to frontier molecular orbital analysis, indicating moderate chemical stability. Compared to urea, the computed first-order hyperpolarizability value (1.138 × 10–32 esu) is higher, indicating possible nonlinear optical behavior. Intramolecular charge transfer interactions inside the molecule were verified by a Natural Bond Orbital (NBO) study. Electrophilic and nucleophilic reactive areas were identified using molecular electrostatic potential (MEP) analysis. Additionally, Lipinski’s rule of five drug-likeness evaluation showed that the molecule has advantageous physicochemical characteristics for possible medicinal use.