Computational Chemistry Approach for the Investigation of Structural, Electronic, Chemical and Quantum Chemical Facets of Twelve Biginelli Adducts

The rising concerns about the Biginelli reaction are mainly attributable to the therapeutic and pharmacological features of Biginelli adducts, especially dihydropyrimidinones (DHPMs). The DFT framework could be used to explore molecular properties such as molecular structures, molecular energies, ionisation potentials, dipole moments, and electronic parameters. It also contributes to the correlative analysis of theoretical and experimental findings through providing valuable perspectives. Using density functional theory (DFT) at the 6-311++G(d,p) basis set, twelve Biginelli adducts were focused to ascertain various structural and chemical parameters. The important structural parameters such as optimized molecular structures, frontier molecular orbital (FMO) analysis, and molecular electrostatic potential analysis were addressed in the present report. In addition, different quantum chemical parameters have been calculated to gain a deeper comprehension of the molecules' synthetic reactivity. The FMO and quantum chemical exploration revealed that BA7 molecule has a lower HOMO-LUMO energy gap, indicating that charge transfer interactions are inevitable within the molecule. The BA7 molecule was also found to have a higher global softness value than the other derivatives. The absolute hardness of the BA6 molecule, on the other hand, is higher. With a value of 2.3228 eV, the BA3 molecule was revealed to have the highest charge transfer.