CREATION OF TEMPERATURE INHOMOGENITIES WITH THE USE OF PELTIER ELEMENT FOR THE MASS-EXCHANGE PROCESSES INTENSIFICATION OF THE OIL AND GAS INDUSTRY

The intensification of technological processes in the oil and gas industry is an urgent task for industrial production. Improving the efficiency of the processes leads to a decrease in the consumption of materials by the apparatus and the cost of their manufacture, an improvement in the quality of the produced product, and simplifies the transportation and installation of equipment. To achieve these goals, a new highly efficient equipment is being developed based on the use of various physical and chemical phenomena, their combinations, and new technological approaches. One of the most effective ways to solve such problems is pulse impact on the materials being processed, in which inhomogeneities of the process driving force are artificially created. The challenge of intensifying the processes occurring during the direct contact of the phases is the need to influence the system being processed locally - in the area of the interface, since it is there that the substances transfer from one phase to another. The object of article's scientific research – mass-exchange process, which is most widespread in oil and gas technology. As a model, the process of liquid evaporation is chosen, on which the separation of mixtures by rectification is based – the main process of the oil and gas processing industry. The heterogeneity of the driving force of the mass transfer process was created using a thermoelectric converter, the principle of which is based on the Peltier effect, in a series of experiments. Such converters allow creation of higher temperature gradient and, consequently, a greater temperature heterogeneity in the investigated system compared with traditional resistance electric heaters at the same energy expenditure. The article discusses the influence of the temperature inhomogenities location on the efficiency of mass-exchange processes, specifically the evaporation process. In experimental studies, the evaporation rate was estimated by measuring the mass evaporation velocity of a liquid. It is noted that the creation of a temperature gradient on the free surface of the liquid phase using a Peltier element with a specific power of 1.8 kW/m2 leads to a twofold intensification of the evaporation process

Synthesis of Enantioenriched Amines by Iron-Catalysed Amination of Alcohols Employing at Least One Achiral Substrate

The synthesis of a broad range of enantioenriched amines by the direct Fe-catalysed coupling of amines with alcohols through the borrowing hydrogen strategy, while at least one of these substrates is achiral is reported. When starting from α-chiral amines and achiral alcohols, a wide range of enantioenriched amine products, including N-heterocyclic moieties can be obtained with complete retention of stereochemistry and the power of this method is demonstrated in the one-step synthesis of known pharmaceuticals from commercially available, simple enantiopure primary amines and achiral alcohols. It was also found that the use of β-branched enantioenriched primary alcohols and achiral amines as reaction partners leads to a partial loss of stereochemical integrity in the final product, however, a systematic optimization enabled partial retention of enantiopurity and possible parameters effecting for racemization were identified.</p

Structural data of phenanthrene-9,10-dicarbonitriles

In this data article, we present the single-crystal XRD data of phenanthrene-9,10-dicarbonitriles. Detailed structure analysis and photophysical properties were discussed in our previous study, "Intermolecular interactions-photophysical properties relationships in phenanthrene-9,10-dicarbonitrile assemblies" (Afanasenko et al., 2020). The data include the intra- and intermolecular bond lengths and angles. (c) 2019 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)

Intermolecular interactions-photophysical properties relationships in phenanthrene-9,10-dicarbonitrile assemblies

Phenanthrene-9,10-dicarbonitriles show various luminescence behaviour in solution and in the solid state. Aggregation patterns of phenanthrene-9,10-dicarbonitriles govern their luminescent properties in the solid state. Single crystal structures of phenanthrene-9,10-dicarbonitriles showed head-to-tail intraplane (or quasi-intraplane) intermolecular interactions and π-stacking patterns with eclipsing of molecules when viewed orthogonal to the stacking plane. The π-stacking interactions were detected in the X-ray structures of phenanthrene-9,10-dicarbonitriles and studied by DFT calculations at the M06–2X/6–311++G(d,p) level of theory and topological analysis of the electron density distribution within the framework of QTAIM method. The estimated strength of the C⋯C contacts responsible for the π-stacking interactions is 0.6–1.1 kcal/mol. The orientation of molecules in crystals depends on the substituents in phenanthrene-9,10-dicarbonitriles. Distinct molecular orientation and packing arrangements in crystalline phenanthrene-9,10-dicarbonitriles ensured perturbed electronic communication among the nearest and non-nearest molecules through an interplay of excimer and dipole couplings. As a result, the intermolecular interactions govern the solid state luminescence of molecules

Structures and photophysical properties of 3,4-diaryl-1H-pyrrol-2,5-diimines and 2,3-diarylmaleimides

Structural features of 3,4-diaryl-1H-pyrrol-2,5-diimines and their derivatives have been studied by molecular spectroscopy techniques, single-crystal X-ray diffraction, and DFT calculations. According to the theoretical calculations, the diimino tautomeric form of 3,4-diaryl-1H-pyrrol-2,5-diimines is more stable in solution than the imino-enamino form. We also found that the structurally related 2,3 exist in the solid state in the dimeric diketo form. 3,4-Diary1-1H-pyrrol-2,5-diimines and 2,3-diarylmaleimides exhibit fluorescence in the blue region of the visible spectrum. The fluorescence spectra have large Stokes shifts. Aryl substituents at the 3,4-positions of 1H-pyrrol-2,5-diimine do not significantly affect fluorescence properties. The insertion of donor substituents into 2,3diarylmaleimides leads to bathochromic shift of emission bands with hyperchromic effect. (C) 2017 Elsevier B.V. All rights reserved

Front Cover Picture:Synthesis of Enantioenriched Amines by Iron-Catalysed Amination of Alcohols Employing at Least One Achiral Substrate (Adv. Synth. Catal. 24/2021)

The Front Cover Picture, designed by Anastasiia Afanasenko, illustrates the methodology for the synthesis of enantioenriched amines by the direct Fe-catalysed coupling of amines with alcohols through the borrowing hydrogen strategy, while at least one of these substrates is achiral. As in the well-known “The Tortoise and the Hare” fable by Aesop, tortoise – stands for chiral amine – won the race retaining the stereochemical integrity in the final product, whereas beta-branched enantioenriched primary alcohol – depicts by the hare – lost the competition due to its racemization that led to the partial loss of the chirality in the target amine. Details can be found in the Research Article by Katalin Barta and collaborators (G. Bottari, A. Afanasenko, A. A. Castillo-Garcia, B. L. Feringa, K. Barta, Adv. Synth. Catal. 2021, 363, 5436–5442; DOI: 10.1002/adsc.202100231).<br/