Study of <i>N</i> ‐methyl‐5‐nitroindazolylacrylonitriles as a Function of Quantum Parameters Employing Density Function Theory Methods: Comparative Theoretical Study and Nonlinear Optical Properties

Abstract

Abstract The synthesis of N ‐methyl‐5‐nitroindazolylacrylonitriles 2 a – l by a Knoevenagel condensation reaction with a series of aldehydes in the presence of piperidine allowed the preparation of the desired products the yields are good to excellent. N ‐Methyl‐5‐nitroindazolylacrylonitriles ( 2 a – l ) were verified by 1 H, 13 C NMR and mass spectrometry. In this current work, the reactivity indices defined within the Conceptual DFT of the targeted molecules through DFT/B3LYP/6‐311G(d,p) calculations were studied. The 1 H NMR, UV‐vis and IR spectroscopy chemical shifts of all synthesized 5‐nitroindazoles 2 a – l were calculated and the results were compared to the results of the experimental data. In this series of compounds, the 2 e has the lowest hyperpolarizability, which results being the most stable and having the least response to nonlinear optics (NLO). In contrast, the compound 2 l has the highest hyperpolarizability, which fallouts being the least stable and having a high response to NLO. Every chemical has a significant three‐dimensional p‐electronic delocalization, which is crucial for understanding NLO responses.