Crystal, spectroscopic and quantum mechanics studies of Schiff bases derived from 4-nitrocinnamaldehyde

Abstract

Two Schiff bases, (E)-1-(4-methoxyphenyl)-N-((E)-3-(4-nitrophenyl)allylidene)methanamine (compound 1) and (E)-N-((E)-3-(4-nitrophenyl)allylidene)-2-phenylethanamine (compound 2) have been synthesized and characterized using spectroscopic methods; time of flight MS, 1H and 13C NMR, FT-IR, UV–VIS, photoluminescence and crystallographic methods. The structural and electronic properties of compounds 1 and 2 in the ground state were also examined using the DFT/B3LYP functional and 6-31 + G(d,p) basis set, while the electronic transitions for excited state calculations were carried out using the TD-DFT/6-31 + G(d,p) method. The Schiff base compounds, 1 and 2 crystallized in a monoclinic crystal system and the P21/c space group. The emission spectra of the compounds are attributed to conjugated π-bond interaction while the influence of the intra-ligand charge transfer resulted in a broad shoulder for 1 and a double emission peak for 2. The calculated transitions at 450 and 369 nm for 1 and 2 respectively are in reasonable agreement with the experimental results. The higher values of dipole moment, linear polarizability and first hyperpolarizability of 1, suggest a better optical property and better candidate for the development of nonlinear optical (NLO) materials.

Synthesis, Crystal Structure, Hirshfeld Surface Analysis, and Computational Study of a Novel Organic Salt Obtained from Benzylamine and an Acidic Component

“…The metal complexes of Schiff bases derived from 4-carboxybenzaldehyde have potential antifungal, antibacterial (Gram positive and Gram negative), cytotoxic, antioxidant, and urease inhibition activities. , Priyadarshini et al have explored quinoline-based Schiff bases for the calculation of their optical and nonlinear optical (NLO) properties. From an experimental point of view, the studies of Kamaal et al and Ani et al are very interesting where they performed experimental investigations to study the NLO properties of Schiff bases consisting of 4-[(2-hydroxy-3-methoxybenzylidene) amino] benzoic acid and methanamine/phenylethanamine derivatives, respectively. In lieu of the immense potential application of Schiff bases and in continuation of our previous research, , we are reporting the synthesis, crystal structure, Hirshfeld surface (HS) analysis, and density-functional theory (DFT) studies of a novel Schiff base.…”

Crystal Structure, Hirshfeld Surface Analysis, and Biological Activities of Schiff-Base Derivatives of 4-Aminoantipyrine

“…The great majority of reports on Schiff bases derived from 4-AAP have concentrated primarily on the use of substituted benzaldehydes, with relatively few reports involving the use of cinnamaldehydes. The presence of a double-bound conjugated with the imino moiety is attractive not only for the synthesis of novel compounds with potential biological activity but also for potential uses in optical applications. , We recently synthesized several Schiff base derivatives obtained from 4-AAP with various cinnamaldehydes and preliminary data show that these compounds present antibacterial activity and antiproliferative activity against several carcinoma cell lines . In order to continue our investigation of these compounds, we report here vibrational (IR), electronic (UV–vis) spectroscopy, electrochemical characterization of these Schiff base derivatives, and X-ray diffraction studies of four compounds.…”

Synthesis, spectroscopic, topological, hirshfeld surface analysis, and anti-covid-19 molecular docking investigation of isopropyl 1-benzoyl-4-(benzoyloxy)-2,6-diphenyl-1,2,5,6-tetrahydropyridine-3-carboxylate

“…Spectroscopic techniques like Fourier Transform Infrared (FTIR), Nuclear Magnetic Resonance (NMR) and Mass Spectroscopy are helpful in establishing the structures of molecules 41 , 42 , 43 , 44 , 45 . Density Functional Theory (DFT) has been used solely and/or in conjunction with experimental methods for understanding the bonding and structural properties, characterization and applications of molecules 46 , 47 , 48 , 49 , 50 .…”