scholarly journals Synthesis, structure, and theoretical studies of a calcium complex of a unique dianion derived from 1-methylpyrrolidin-2-one

Author(s):  
Ray J. Butcher ◽  
Andrew P. Purdy ◽  
Paul A. Brown ◽  
Daniel Gunlycke

The title compound, catena-poly[[tetrakis(1-methylpyrrolidin-2-one-κO)calcium(II)]-μ-(E)-1,1′-dimethyl-2,2′-dioxo-1,1′,2,2′-tetrahydro-[3,3′-bipyrrolylidene]-5,5′-bis(thiolato)-κ2 O:O′], [Ca(C10H8N2O2S2)(C5H9NO)4] n , 1, crystallizes in the triclinic space group P\overline{1}. The crystal studied was twinned by non-merohedry via two different twofold operations, about the normals to (001) and (1\overline{1}0), giving four twin domains with refined occupancies of 0.412 (4), 0.366 (4), 0.055 (1), 0.167 (4). The Ca atoms are located on centers of inversion. Each Ca is surrounded by four 1-methylpyrrolidin-2-one (NMP) ligands and coordinated through one of the two O atoms to two (E)-1,1′-dimethyl-2,2′-dioxo-1,1′,2,2′-tetrahydro-[3,3′-bipyrrolylidene]-5,5′-bis(thiolate), [C10H8N2O2S2]2−, dianions (abbreviation: DMTBT). This dianion thus facilitates the formation of a 1-D polymer, which propagates in the [011] direction. These ribbons are linked by intermolecular C—H...S interactions. Each Ca atom is in an octahedral CaO6 six-coordinate environment with Ca—O bond lengths ranging from 2.308 (6) to 2.341 (6) Å, cis bond angles ranging from 88.2 (2) to 91.8 (2)° and the trans angles all 180° due to the Ca atoms being located on centers of inversion. Theoretical calculations were carried out using density functional theory (DFT) and the results showed that although the central DMTBT dianion is planar there is likely some resonance across the central bond between both azapentyl rings, but this is not sufficient to establish a ring current. The calculated UV–vis spectrum shows a peak at 625 nm, which accounts for the deep blue–purple color of solutions of the complex.

2018 ◽  
Author(s):  
Mihails Arhangelskis ◽  
Athanassis Katsenis ◽  
Novendra Novendra ◽  
Zamirbek Akimbekov ◽  
Dayaker Gandrath ◽  
...  

By combining mechanochemical synthesis and calorimetry with theoretical calculations, we demonstrate that dispersion-corrected periodic density functional theory (DFT) can accurately survey the topological landscape and predict relative energies of polymorphs for a previously inaccessible fluorine-substituted zeolitic imidazolate framework (ZIF). Experimental screening confirmed two out of three theoretically anticipated polymorphs, and the calorimetric measurements provided an excellent match to theoretically calculated energetic difference between them.<br>


2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Ali I. Ismail

Ibrutinib, a Bruton’s tyrosine kinase that plays an essential role in the B-cell development and cancer cells, has been recently approved to treat chronic, lymphocytic, and other types of leukemia. This study focused on investigating ibrutinib by its electronic transitions, vibrational frequencies, and electrospray mass spectra. The experimental peaks for electronic spectrum were found at 248.0 and 281.0 nm, whereas the νC = 0 stretching frequency was found at 1652.4 and 1639.19 cm−1. These experimental properties were compared with the corresponding theoretical calculations in which density functional theory was applied. The optimized structure was obtained with the calculations using a hybrid function (B3LYP) and high-level basis sets [6-311G++(d,p)]. Most of the calculated vibrational frequencies showed a relatively good agreement with the experimental ones. The electronic transitions of ibrutinib calculated using time-dependent DFT method were performed at two different solvation methods: PCM and SMD. The mass spectrum of ibrutinib, its fragments, and its isotopic pattern agreed well with the expected spectra.


2021 ◽  
Vol 32 ◽  
Author(s):  
Hieu Nguyen-Truong

We calculate excitation spectra of cubic perovskites ATiO3 (A = Ca, Sr, Ba, Pb). The calculations are performed within the time-dependent density functional theory, including local field effects. The theoretical calculations show that the perovskites have a plasmon mode at around 12 eV, which is not observed in experiments.


Proceedings ◽  
2019 ◽  
Vol 41 (1) ◽  
pp. 28
Author(s):  
Dawid Zych

In this work, the necessity of synthesis of 1,3-di(hetero)aryl-7-substituted pyrenes is presented based on the results of theoretical calculations by using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) by using Gaussian 09 program with B3LYP exchange-correlation functional and 6-31G** basis set. What is more, the synthetic routes with feasible reagents and conditions are presented. The subject of theoretical considerations are two pyrene derivatives which contain at position 1 and 3 pyrazolyl substituents and at position 7 amine (1) or boron (2) derivative. The theoretical calculations were also performed for the osmium complexes with mentioned ligands (3 and 4). The influence of electron-donating/accepting character of the substituent at position 7 of pyrene on the properties of molecules has been established.


2020 ◽  
Vol 44 (5) ◽  
pp. 1254-1264
Author(s):  
Shaya AL-RAQA ◽  
İpek ÖMEROĞLU ◽  
Doğan ERBAHAR ◽  
Mahmut DURMUŞ

Phenyl-4,4-di(3,6-dibutoxyphthalonitrile) (3) was synthesized by the reaction of 1,4-phenylenebisboronic acid (1) and 4-bromo-3,6-dibutoxyphthalonitrile (2), using Suzuki cross-coupling reaction. The newly synthesized compound (3) was characterized by FT-IR, MALDI-MS, ESI-MS, 1H-NMR, 13C-NMR, and 13C-DEPT-135-NMR. The fluorescence property of phenyl-4,4-di(3,6- dibutoxyphthalonitrile) (3) towards various metal ions was investigated by fluorescence spectroscopy, and it was observed thatthe compound (3) displayed a significantly ‘turn-off’ response to Fe3+, which was referred to 1:2 complex formation between ligand (3) and Fe3+. The compound was also studied via density functional theory calculations revealing the interaction mechanism of the molecule with Fe3+ ions.


RSC Advances ◽  
2020 ◽  
Vol 10 (57) ◽  
pp. 34493-34500
Author(s):  
Mei-Chun Huang ◽  
Wei-Hao Chen ◽  
Chen-Wei Huang ◽  
Kuei-Yen Huang ◽  
Jia-Cherng Horng ◽  
...  

The low-wavenumber Raman spectra in combination with theoretical calculations via solid-state density functional theory (DFT)-D3 are displayed. The vibrational structures and interaction with solvent of poly-l-proline and the oligoproline P12 series are identified.


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