Synthesis, structural and vibrational spectroscopic investigation of molecules: N-n-butyl, S-2-nitro-1-phenylethyl dithiocarbamate and N-n-butyl, S-2-nitro-1-(4-flurophenyl)ethyl dithiocarbamate

Abstract

The present work deals with the synthesis as well as molecular modeling and vibrational spectroscopic analysis of two biorelevant molecules, namely N-n-butyl, S-2-nitro-1-phenylethyl dithiocarbamate and N-n-butyl, S-2-nitro-1-(4-flurophenyl)ethyldithiocarbamate in gas phase. The optimization of the molecular structures of these compounds was performed at Density Functional Theory with exchange functional B3LYP and Hartree-Fock theory. The customary basis set 6-31++G(d,p) was employed during computations at both the level. The experimental FTIR spectra of both thecompounds were recorded in range 4000–400 cm-1 to correlate with the calculated spectra of the compounds. The normal coordinate analysis (NCA) method was used for the calculation of potential energy distributions. Most of the DFT calculated frequencies were found to agree with the experimental FTIR frequencies. To ensure the stability of electronic structures of these compounds the natural bond orbital analysis (NBO) for each compound was also performed and the analysis revealed that the intramolecular interactions resulting from overlapping of bonding and antibonding orbitals provoke the intramolecular charge transfer (ICT) causing stabilization of the system. The frontier bond orbital analysis was also performed to study the interaction profile of the compounds. © 2020 Elsevier B.V.