Quantum chemical studies and spectroscopic investigations on 2-amino-3-methyl-5-nitropyridine by density functional theory

Abstract

Quantum chemical calculations on energy and molecular structure of 2-amino-3-methyl-5-nitropyridine (2A3M5NP) have been attempted by implementing DFT/B3LYP method using 6-311G (d,p), 6-311G++ (d,p) and cc-pVTZ basis sets. The optimized geometry and the vibrational analysis for energetically most stable configuration, are carried out theoretically by using B3LYP/cc-pVTZ basis set. The computed vibrational frequencies were scaled by using scaling factors and compared with the experimental Fourier Transform Infra-Red (FTIR) solid phase spectrum in the region 4000-400 cm −1 and FT-Raman spectrum in the region 4000-100 cm −1 . The complete vibrational assignments, analysis and correlation of fundamental modes of the compound have been carried out using the potential energy distribution (PED). The intramolecular charge transfer, hyperconjugative interaction of the compound is investigated from natural bonding orbital (NBO) analysis. The UV-Visible spectrum of 2A3M5NP was obtained with ethanol as a solvent. The electronic properties such as HOMO (Highest Occupied Molecular Orbital) and LUMO (Lowest Unoccupied Molecular Orbital) energies are determined by B3LYP/cc-pVTZ basis set. The electronic absorption spectrum of the compound was studied from UV-Visible analysis by using time-dependent density functional theory (TD-DFT). The electron density distribution and chemical reactive sites of 2A3M5NP were analyzed from molecular electrostatic potential (MEP) analysis and frontier molecular orbital (FMO) analysis.

A Comparative Study on Electro-Optic Effects of Organic N-Benzyl-2-Methyl-4-Nitroaniline and Morpholinium 2-Chloro-4-Nitrobenzoate Doped in Nematic Liquid Crystals E7

“…As shown in Table 2, the increments in µ, α, and ∆α were more significant than the decrement in S of LC mixture with the addition of organic molecule, indicating that the increased ∆ε was mainly attributed to the increments in µ, α, and ∆α according to Equations (1)- (3). Figure 6a,b show the normalized absorbance peaks for 5CB, BNA, 5CB + BNA, M2C4N, and 5CB + M2C4N appear at 292 (π → π *), 345, 339, 315, and 330 nm (n → π *), respectively, due to the presence of nitro, amine, and methyl groups [43,44]. By correlating the optimized geometries (Figure 2), the BNA dopant shifts the absorbance peak of the LCs toward the long-wavelength side, due to the amine group in BNA has a strong intermolecular interaction with the CN group in LCs.…”

“…Figure 6 a,b show the normalized absorbance peaks for 5CB, BNA, 5CB + BNA, M2C4N, and 5CB + M2C4N appear at 292 (π → π *), 345, 339, 315, and 330 nm ( n → π *), respectively, due to the presence of nitro, amine, and methyl groups [ 43 , 44 ]. By correlating the optimized geometries ( Figure 2 ), the BNA dopant shifts the absorbance peak of the LCs toward the long-wavelength side, due to the amine group in BNA has a strong intermolecular interaction with the CN group in LCs.…”

Spectroscopic characterization, DFT studies, molecular docking and cytotoxic evaluation of 4‐nitro‐indole‐3‐carboxaldehyde: A potent lung cancer agent

“…The asymmetric stretching and symmetric stretching modes of NO 2 normally occur in the region at 1570 to 1485 cm −1 and 1370 to 1320 cm −1 , respectively 50 . In the NICA molecule, a strong band, observed at 1578 cm −1 , in FT‐IR spectrum and 1577 cm −1 in FT‐Raman spectrum was assigned to asymmetric stretching of NO 2 .…”

Synthesis, X-ray crystal structure, IR and Raman spectroscopic analysis, quantum chemical computational and molecular docking studies on hydrazone-pyridine compound: As an insight into the inhibitor capacity of main protease of SARS-CoV2

“…These transitions of oscillator strengths ( f ) 0.1551/0.9191 and excitation energies (eV) 4.1801/3.7101 were obtained from simulation results and these data are given in Table 4 . The π-π* transitions of the CCPEHP arise from the electrons of the pyridine ring, while the n-π* band is due to hydrazone groups of atoms [ 2 , 58 ].

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“…It also plays a key role in catalyzing biological and chemical systems. Pyridine derivatives contain multi-functional groups and streptonigrone, steroidigrin, and lavendamycin of these groups have been reported as anti-cancer drugs and cerivastatin as HMG-CoA enzyme inhibitor drugs [ 2 , 3 ]. The importance of pyridine and phenol vibration spectra in biological and industrial systems attracts great attention from a spectroscopic point of view [4] .…”