Computational study of the chemical reactivity properties of 4-[(1H-indol-3-ylmethylene)-amino] benzenesulfonamide derivatives

Abstract

This study represents an integral approach towards understanding the electronic and structural aspects of 4-[(1H-indol-3-ylmethylene)-amino] benzenesulfonamide derivatives 1-4 by the DFT/B3LYP method and 6-31G (d,p) basis set. The geometrical parameters of title compounds are also obtained by the same method. From the MEP map it is evident that the negative electrostatic potential regions are mostly localized over the sulfamide function and are possible sites for electrophilic attack and positive regions are localized around the hydrogen atoms indicating possible sites for nucleophilic attack. The frontier molecular orbital is determined by means the HOMO and LUMO analysis which is used to explain the charge transfer within the molecule. The chemical reactivity descriptors were calculated to study the reactive sites within molecules and the results show that compound 3 is the most reactive. Furthermore the Mulliken population analysis on atomic charges is calculated and interpreted. Natural bond orbital (NBO) analysis was carried out to interpret the hyperconjugative interactions. Nonlinear optical property calculations of the compounds 1-4 indicate that these compounds cannot be used as a NLO material.