scholarly journals 1,3,4-Thiadiazole-Containing Azo Dyes: Synthesis, Spectroscopic Properties and Molecular Structure

Molecules ◽  
2020 ◽  
Vol 25 (12) ◽  
pp. 2822
Author(s):  
Agnieszka Kudelko ◽  
Monika Olesiejuk ◽  
Marcin Luczynski ◽  
Marcin Swiatkowski ◽  
Tomasz Sieranski ◽  
...  
Keyword(s):  
Azo Dyes ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Spectroscopic Properties ◽  
Radiation Absorption ◽  
Functional Theory ◽  
Chemical Structures ◽  
Vis Spectroscopy ◽  
High Yields

Three series of azo dyes derived from 2-amino-5-aryl-1,3,4-thiadiazoles and aniline, N,N-dimethylaniline and phenol were synthesized in high yields by a conventional diazotization-coupling sequence. The chemical structures of the prepared compounds were confirmed by 1H-NMR, 13C-NMR, IR, UV-Vis spectroscopy, mass spectrometry and elemental analysis. In addition, the X-ray single crystal structure of a representative azo dye was presented. For explicit determination of the influence of a substituent on radiation absorption in UV-Vis range, time-dependent density functional theory calculations were performed.

scholarly journals N-Heterocyclic carbene-catalyzed enantioselective hetero-[10 + 2] annulation

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Qiupeng Peng ◽  
Shi-Jun Li ◽  
Bei Zhang ◽  
Donghui Guo ◽  
Yu Lan ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Higher Order ◽  
Heterocyclic Carbenes ◽  
Wide Scope ◽  
Functional Theory ◽  
One Step ◽  
High Yields ◽  
Powerful Strategy

AbstractHigher-order cycloadditions are a powerful strategy for the construction of polycycles in one step. However, an efficient and concise version for the induction of asymmetry is lacking. N-heterocyclic carbenes are widely used organocatalysts for asymmetric synthesis and could be an ideal choice for enantioselective higher-order cycloadditions. Here, we report an enantioselective [10 + 2] annulation between catalytically formed aza-benzofulvene intermediates and trifluoromethyl ketone derivatives. This protocol exhibits a wide scope, high yields, and good ee values, reflecting a robust and efficient higher-order cycloaddition. Density functional theory calculations provide an accurate prediction of the reaction enantioselectivity, and in-depth insight to the origins of stereocontrol.

scholarly journals UV–Vis Absorption Properties of New Aromatic Imines and Their Compositions with Poly({4,8-bis[(2-Ethylhexyl)oxy]Benzo[1,2-b:4,5-b′]Dithiophene-2,6-diyl}{3-Fluoro-2-[(2-Ethylhexyl)Carbonyl]Thieno[3,4-b]Thiophenediyl})

Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4191 ◽  
Author(s):  
Agnieszka Gonciarz ◽  
Robert Pich ◽  
Krzysztof Artur Bogdanowicz ◽  
Beata Jewloszewicz ◽  
Wojciech Przybył ◽  
...  
Keyword(s):  
Absorption Spectra ◽  
Organic Solar Cells ◽  
Density Functional ◽  
Bulk Heterojunction ◽  
Theoretical Calculations ◽  
Dft Methods ◽  
Functional Theory ◽  
Chemical Structures ◽  
Vis Spectroscopy ◽  
Aromatic Imines

In this paper, four new aromatic imines containing at least one thiazole-based heterocycle were analyzed in detail by UV–Vis spectroscopy, taking into consideration their chemical structures and interactions with PTB7, a known polymeric electron donor widely used in bulk heterojunction organic solar cells. It is demonstrated that the absorption spectra of the investigated active compositions can be modified not only by changing the chemical structure of imine, but also via formulations with PTB7. For all investigated imines and PTB7:imine compositions, calibration curves were obtained in order to find the optimum concentration in the composition with PTB7 for expansion and optimization of absorption spectra. All imines and PTB7:imine compositions were investigated in 1,2-dichlorobenzene by UV–Vis spectroscopy in various concentrations, monitoring the changes in the π–π* and n–π* transitions. With increasing imine concentrations, we did not observe changes in absorption maxima, while with increasing imine concentrations, a hypochromic effect was observed. Finally, we could conclude that all investigated compositions exhibited wide absorptions of up to 800 nm and isosbestic points in the range of 440–540 nm, confirming changes in the macromolecular organization of the tested compounds. The theoretical calculations of their vibration spectra (FTIR) and LUMO–HOMO levels by Density Functional Theory (DFT) methods are also provided. Finally, IR thermal images were measured for organic devices based on imines and the imine:PTB7 composite.

scholarly journals Physicochemical Insight into Coordination Systems Obtained from Copper(II) Bromoacetate and 1,10-Phenanthroline

Molecules ◽  
2020 ◽  
Vol 25 (22) ◽  
pp. 5324
Author(s):  
Ewelina Krejner ◽  
Tomasz Sierański ◽  
Marcin Świątkowski ◽  
Marta Bogdan ◽  
Rafał Kruszyński
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Building Blocks ◽  
Radiation Absorption ◽  
Ir Absorption ◽  
Bromoacetic Acid ◽  
Functional Theory ◽  
Hirshfeld Analysis ◽  
Coordination Systems

Two different coordination compounds of copper were synthesized from the same building blocks (1,10-phenanthroline, bromoacetate anions, and copper cations). The synthesis parameters were carefully designed and evaluated to allow the change of the resulting compounds molecular structure, i.e., formation of mononuclear (bromoacetato-O,O’)(bromoacetato-O)aqua(1,10-phenanthroline-N,N’)copper(II) and dinuclear (μ-bromido-1:2κ2)bis(μ-bromoacetato-1κO,2κO’)bis(1,10-phenanthroline-N,N’)dicopper(II) bromoacetate bromoacetic acid solvate. The crystal, molecular and supramolecular structures of the studied compounds were determined and evaluated in Hirshfeld analysis. The UV-Vis-IR absorption and thermal properties were studied and discussed. For the explicit determination of the influence of compounds structure on radiation absorption in UV-Vis range, density functional theory and time-dependent density functional theory calculations were performed.

scholarly journals Structural determination of niobium-doped silicon clusters by far-infrared spectroscopy and theory

2016 ◽  
Vol 18 (8) ◽  
pp. 6291-6300 ◽  
Author(s):  
Xiaojun Li ◽  
Pieterjan Claes ◽  
Marko Haertelt ◽  
Peter Lievens ◽  
Ewald Janssens ◽  
...  
Keyword(s):  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Far Infrared ◽  
Silicon Cluster ◽  
Silicon Clusters ◽  
Functional Theory ◽  
Infrared Multiple Photon Dissociation ◽  
Niobium Doped ◽  
Doped Silicon

The structures of niobium doped silicon cluster cations are determined by a combination of infrared multiple photon dissociation spectroscopy and density functional theory calculations.

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