Synthesis, spectroscopic, SC-XRD characterizations and DFT based studies of ethyl2-(substituted-(2-benzylidenehydrazinyl))thiazole-4-carboxylate derivatives

Abstract

In the present study, ethyl-2-(2-(2-methylbenzylidene)hydrazinyl)thiazole-4-carboxylate (1) and ethyl-2-(2-(4-bromobenzylidene)hydrazinyl)thiazole-4-carboxylate (2) were synthesized. The characterization of synthesized compounds was accomplished by employing analytical techniques of spectroscopy as 1H NMR, 13C NMR, FT-IR, UV–Vis and final confirmation was furnished using single crystal X-ray diffraction (SC-XRD) technique. The informations regarding optimized geometry, nonlinear optical (NLO) properties and frontier molecular orbitals (FMOs) were obtained by applying B3LYP level of DFT and 6-311 + G(d,p) basis set. As a whole, the computed results from DFT were found in close agreement to that of experimental results. The combination of B3LYP level of time dependent DFT (TDDFT) and 6-311 + G (d,p) basis set were employed for computational calculations of vertical electronic transition states. The stability on account of hyperconjugation and charge delocalization factors was evaluated through the study of natural bond orbitals (NBO). The capabilities of the title compounds with respect to charge transfer and involvement of various sites in chemical activities were evaluated quantitatively by employing the analysis involving frontier molecular orbitals (FMOs). The studies revealed that the compounds possess sizable NLO character as the NLO properties of urea molecule were found smaller as compared to the compounds under investigation which means that such compounds are significant in perspective of technology applications.