Electronic structure theory study of the reactivity and structural molecular properties of halo-substituted (F, Cl, Br) and heteroatom (N, O, S) doped cyclobutane

Abstract

Cyclobutane and its halo-substituted derivatives and its heteroatom doped derivatives have been extensively investigated in this study because of the vast applications and interesting chemistry associated with them, the vibrational assignments, Natural Bond Orbital (NBO) analysis, Conceptual Density Functional Theory, Quantum Mechanical Descriptors and Molecular Electrostatic Potential (MEP) analysis have been explored in this study. The corresponding wavenumbers of the studied compounds have as well been assigned by Potential Energy Distribution analysis. Several inter and intramolecular hyperconjugative interactions within the studied compounds have been revealed by the NBO analysis with a confirmation of geometric hybridization and electronic occupancy. The compounds reactivity was observed to decrease down the halo group in manners such as the stability, both were observed to decrease from azetidine to thietane. The distribution of charge was observed to be affected by the ring substituent as observed from the charge population analysis; in addition, adjacent atoms are very much affected by the inherent properties of the substituted atoms. The NBO result suggests that the molecules are stabilized by lone pair delocalization of electrons from the substituted atoms and molecular electrostatic potential (MEP) studies revealed that substituted halogens and doped heteroatoms are important and most probable sites of electrostatic interactions.