Synthesis and DFT Quantum Chemical Calculations of 2-Oxopyrimidin-1(2H)-yl-Urea and Thiorea Derivatives

2019 ◽  
Vol 41 (5) ◽  
pp. 841-841
Author(s):  
Murat Saracoglu Murat Saracoglu ◽  
Zulbiye Kokbudak Zulbiye Kokbudak ◽  
Esra Yalcin and Fatma Kandemirli Esra Yalcin and Fatma Kandemirli

A series of the new 2-oxopyrimidin-1(2H)-yl-urea (3a-c) and thiourea (4a-d) derivatives were synthesized by the reaction of arylisocyanates (2a-c) or arylisothiocyanates (2d-g) and the 1-amino-5-(4-methoxybenzoyl)-4-(4-methoxyphenyl)pyrimidin-2(1H)-one (1). The structures of the compounds 3a-c and 4a-d were characterized by elemental analysis, FT-IR, 1H and 13C-NMR spectroscopic techniques. In addition to experimental study in order to find molecular properties, quantum-chemical calculations of the synthesized compounds were carried out by using DFT/B3LYP method with basis set of the 6-311G(d,p). Quantum chemical features such as HOMO, LUMO, HOMO-LUMO energy gap, Ionization potential, chemical hardness, chemical softness, electronegativity, chemical potential, dipole moment etc. values for gas and solvent phase of neutral molecules were calculated and discussed.

2019 ◽  
Vol 41 (3) ◽  
pp. 479-479
Author(s):  
Murat Saracoglu Murat Saracoglu ◽  
Zulbiye Kokbudak Zulbiye Kokbudak ◽  
Zeynep imen and Fatma Kandemirli Zeynep imen and Fatma Kandemirli

In this study, a convenient procedure for the preparation of pyrazolo[1,5-c]pyrimidin-7(1H)-one derivatives is described. The new pyrazolo[1,5-c]pyrimidin-7(1H)-one derivatives (2a, b) were synthesized from the cyclocondensation reaction of the compounds 1-amino-5-(4-methoxybenzoyl)-4-(4-methoxyphenyl)pyrimidin-2(1H)-one (1a) and 1-amino-5-(4-methylbenzoyl)-4-(4-methylphenyl)pyrimidin-2(1H)-one (1b) with α-chloroacetone. The structures of the compounds (2a, b) were characterized by elemental analysis, FT-IR, 1H-NMR and 13C-NMR spectroscopic techniques. In addition to experimental study in order to find molecular properties, quantum-chemical calculations of the new pyrazolo[1,5-c]pyrimidin-7(1H)-one derivatives (2a, b) were carried out by using DFT/B3LYP method with the 6-311G(d,p) and 6-311++G(2d,2p) basic sets. Quantum chemical features such as HOMO, LUMO, HOMO-LUMO energy gap, chemical hardness, chemical softness, electronegativity, chemical potential, dipole moment etc. values for gas and solvent phase of neutral molecules were calculated and discussed.


2020 ◽  
Vol 42 (5) ◽  
pp. 746-746
Author(s):  
Murat Saracoglu Murat Saracoglu ◽  
Zulbiye Kokbudak Zulbiye Kokbudak ◽  
M Izzettin Yilmazer and Fatma Kandemirli M Izzettin Yilmazer and Fatma Kandemirli

Pyrimidine derivatives have biological and pharmacological properties. Therefore, in this study we focused on the synthesis various Pyrimidine derivatives to make noteworthy contributions this class of heterocyclic compounds. In the present study, the new compounds (4-6) were obtained by the reactions of 1-amino-5-benzoyl-4-phenylpyrimidin-2(1H)-one (1), 1-amino-5-(4-methylbenzoyl)-4-(4-methylphenyl)pyrimidin-2(1H)-one (2) and 1-amino-5-(4-methoxybenzoyl)-4-(4-methoxyphenyl)pyrimidin-2(1H)-one (3) with dimethyl acetylenedicarboxylate. The structures of these compounds were proved by elemental analysis, FT-IR, 1H and 13C-NMR spectra. In addition to, quantum chemical calculations were made to find molecular properties of the pyrimidin-1(2H)-ylaminofumarate derivatives (4-6) by using DFT/B3LYP method with 6-311++G(2d,2p) basis set. Quantum chemical features such as EHOMO, ELUMO, energy gap, ionization potential, chemical hardness, chemical softness, electronegativity etc. values for gas and solvent phase of neutral molecules were calculated and discussed.


2022 ◽  
Vol 12 ◽  
Author(s):  
Rameshwar K. Dongare ◽  
Shaukatali N. Inamdar ◽  
Radhakrishnan M. Tigote

Herein, we report the density functional study of benzoyl thiourea derivatives linked to morpholine and piperidine to evaluate their antifungal activity. Overall six compounds BTP 1-3 and BTM 4-6 were optimized with DFT using the B3LYP method with 6-31G(d,p) basis set. The molecular geometry, bond lengths, bond angles, atomic charges and HOMO-LUMO energy gap have been investigated. The structural parameters have been compared with the reported experimental results and structure- antifungal activity relationship is explored in details. The calculated results from DFT were discussed using all Quantum chemical parameters of the compounds. Introduction: Benzoyl thiourea derivatives linked with morpholine and piperidine were reported to have good antifungal activity. Objective: To find the correlations between the quantum chemical calculations and the antifungal activity for the benzoyl thiourea derivatives linked with morpholine and piperidine. Method: Optimization was carried out with DFT using B3LYP method utilizing 6-31G(d,p) basis set. Results: A good correlation between the quantum chemical calculations and the antifungal activity for the benzoyl thiourea derivatives linked with morpholine and piperidine was found. Conclusion: The DFT study of benzoyl thiourea derivatives linked to morpholine and piperidine was evaluated for their antifungal activity and it showed good correlations of activity with the quantum chemical parameters.


Quantum chemical calculations of molecular geometry, HOMO-LUMO, Mulliken charge distributions and vibrational assignments of 4-methoxyaniline hydroquinone (4MAHQ) were carried out by DFT (B3LYP) and HF methods. Spectral analysis on 4MAHQ has been studied both by the computational and experimental methods to assign vibrational modes of all the functional groups. The investigation is extensive to calculate the FMOs, population analysis, Molecular Electrostatic Potential and Non Linear Optical efficiency of 4MAHQ. The electron affinity, ionization and chemical potential, electrophilicity index, chemical hardness, electro negativity and global softness of 4-methoxyaniline hydroquinone were calculated by FMO analysis


2015 ◽  
Vol 19 (05) ◽  
pp. 651-662 ◽  
Author(s):  
Hossein Kavousi ◽  
Abdolreza Rezaeifard ◽  
Heidar Raissi ◽  
Maasoumeh Jafarpour

The effect of different electronic and structural nitrogen donors (L) on the N ( ax )- Mn - O properties in the high valent manganese-oxo meso-tetraphenylporphyrin intermediate is investigated by the density functional B3LYP method with 6-31g* basis set. The geometric structures, frontier molecular orbitals, thermodynamic parameters and physical properties such as chemical potential and chemical hardness of [( TPP )( L ) MnO ]+ complexes in the gas phase as well as water solution are calculated. Our theoretical results confirm that the Mn - O distances in [( TPP )( L ) MnO ]+ species decrease by replacing imidazoles with pyridines, amins as well as electron-poor and hindered nitrogen donors resulting from extending the Mn – N ( ax ) bonds. These results are supported by vibrational frequencies, atoms in molecules (AIM) and natural bond orbital (NBO) analysis. It is worth mentioning that the co-catalytic activity trend of different nitrogen donors observed experimentally in the presence of title Mn porphyrin is consistent with the calculated Mn – N ( ax ) and Mn – O bond lengths in this work.


2017 ◽  
Vol 31 (6) ◽  
pp. 729-744 ◽  
Author(s):  
Feride Akman

In this article, coumarin-based random copolymer which can be utilized for atom transfer radical polymerization was investigated both theoretically and experimentally. The thermal degradation mechanism and the activation energies ( Ea) were obtained by means of the Coats–Redfern (CR), Tang, and Flynn–Wall–Ozawa (FWO) methods. The thermal degradation reaction mechanism for random copolymer obeyed the phase boundary model (contracting volume, R3) of solid-state mechanism. The thermodynamic properties in the range from 100 K to 500 K have been obtained. The calculated HOMO–LUMO energy gap and electronic properties, such as chemical hardness ( η), electron affinity ( A), chemical potential ( μ0), global softness ( ζ), electronegativity ( χ), global electrophilicity ( ω), and dipole moment ( μ), were investigated and discussed. The molecular electrostatic potential analysis of the random copolymer was also computed.


2017 ◽  
Vol 1 (3) ◽  
pp. 1-37
Author(s):  
D. Sumathi ◽  
H. Saleem ◽  
A. Nathiya ◽  
N. RameshBabu ◽  
D. Usha

A combined experimental and theoretical study on molecular and vibrational structure of E-N¢ (ICINH) had been carried out. The FTIR, FT-Raman and UV-Vis spectra of ICINH were recorded in the solid phase. The optimized geometry was calculated by B3LYP method with 6-311++G(d,p) level of basis set. The harmonic vibrational frequencies, IR intensities and Raman scattering activities of the title compound were calculated at same level of theory. The scaled theoretical wavenumber showed very good agreement with the experimental values. The mulliken charges and thermodynamic functions of the ICINH were also performed at same level of theory. NLO and a study on the electronic properties such as excitation energies and wavelength, were performed by TD-DFT approach. HOMO–LUMO energy gap was also calculated and interpreted.


2021 ◽  
Vol 14 (2) ◽  
pp. 139-154

Abstract: Here, an attempt is made to theoretically study and predict the electronic and spectroscopic (UV-Vis and IR) and structural properties, quantum chemical descriptors and subsequent application of diacetylaminoazopyrimidine in dye-sensitized solar cells (DSSCs). Ground- and excited-state time-dependent density functional theory (TD-DFT) calculations were carried out using material studio and ORCA software, respectively. The computed ground-state energy gap, chemical hardness, chemical softness, chemical potential, electronegativity and electrophilicity index are: 3.60 eV, 1.80 eV, 0.56 eV, 4.49 eV, -4.49 eV and 5.68, respectively. Conversely, the DFT-predicted excited-state quantum chemical descriptors are: 1.67 eV, 0.83 eV, 1.20 eV, 4.71 eV and -4.71 eV, corresponding to the energy gap, chemical hardness, chemical softness, chemical potential and electronegativity, respectively. Furthermore, vibrational frequency calculations confirm the presence of some key functional groups (N=N, C=O, C-H) present in the dye molecules. The computed optoelectronic parameters, such as light-harvesting efficiency, electron injection and open-circuit voltage are 0.06 eV, -8.59 eV and -5.75 eV, respectively. Overall, the dye possesses a relatively good current conversion efficiency as compared to other dyes studied in the literature; hence, it could be used as a novel material for photovoltaic technological applications. Keywords: Diacetylaminoazopyrimidine, DFT, Excited state, Spectroscopy, DSSCs.


2021 ◽  
Vol 33 (11) ◽  
pp. 2817-2825
Author(s):  
Mohammed Alsawat ◽  
Hamdy S. El-Sheshtawy ◽  
Tariq Altalhi ◽  
Amine Mezni ◽  
Tushar Kumeria ◽  
...  

The metformin perchlorate (MetH+·ClO4 −) with a new crystal structure was synthesized, characterized and comparatively studied with other metformin salts of Cl− and NO3 − by different spectroscopic techniques such as TGA-DSC and FT-IR as well as UV-visible spectroscopic studies. DFT calculations were performed by rwb97xd and 6-31G+(d,p) basis set for structure optimization and frequency calculations. Similar to MetH+·Cl−, the crystal packing of MetH+·ClO4 −andMetH+·NO3 − were stabilized by hexagonal hydrogen bond elongated network. The relative stability and reactivity of these salts were determined by exploring the DFT chemical descriptors such as chemical hardness, electronegativity, electronic chemical potential, electrophilicity and hardness. These calculations were employed to get the subset of variables that could categorize the metformin salts according to their reactivity.


2020 ◽  
Author(s):  
Sopanant Datta ◽  
Taweetham Limpanuparb

<p>This article presents theoretical data on geometric and energetic features of halobenzenes and xylenes. Data were obtained from <i>ab initio</i> geometry optimization and frequency calculations at HF, B3LYP, MP2 and CCSD levels of theory on 6-311++G(d,p) basis set. In total, 1504 structures of halobenzenes, three structures of xylenes and one structure of benzene were generated and processed by custom-made codes in Mathematica. The quantum chemical calculation was completed in Q-Chem software package. Geometric and energetic data of the compounds are presented in this paper as supplementary tables. Raw output files as well as codes and scripts associated with production and extraction of data are also provided.</p>


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