Prehliadanie podľa Autor "Mkrtchyan, Satenik"
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Položka Mechanochemical sequential deoxygenative cross-coupling reactions of phenols under ruthenium-nickel catalysis(Multidisciplinary Digital Publishing Institute : Basel, 2025) Mkrtchyan, Satenik; Purohit, Vishal; Jakubczyk, Michał; Prajapati, Vaibhav D.; Prajapati, Ronak V.; Garcia, Michael G.; Karpun, Yevhen; Yepishev, Vitaliy; Saini, Manoj K.; Sarfaraz, Sehrish; Ayub, Khurshid; Addová, Gabriela; Filo, Juraj; Iaroshenko, Viktor O.One of the key modeling procedures is model verification, which ensures its reliability and confidence. In many respects, the length of the crown is an interesting biophysical property. Precise determination of crown length can be one of the components used in estimating the mass of needles or leaf area index (LAI), and consequently the amount of transpiration or the amount of carbon dioxide bound, which is crucial in the context of climate change. The objective of this study was to calculate the length of the crown Pinus sylvestris using an allometric model and to compare these results with the actual ones to establish the degree of discrepancy. The model that was tested was based on three predictor variables, i.e., diameter at breast height, tree height, and stand density index. The verification was carried out using empirical data collected for 300 sample trees on 20 experimental plots located in south-western Poland. All the stands were pine monocultures located in the habitats of fresh or mixed fresh forest aged from 28 to 40 years. The studied stands differed in terms of diameter at breast height, height, and density (0.68–1.81). The comparison between empirical (𝐶𝐿𝑒𝑚𝑝 ) and calculated (𝐶𝐿𝑐𝑎𝑙 ) mean crown lengths in the stand using the model was expressed by the correlation coefficient’, which was R = 0.955, with a divergence (±) of 4.57%. The tested model is dedicated to calculating the length of tree crowns at the population level. The model uses a density index, which is a constant value for all trees within the area. Further work is needed to improve the model and allow for precise calculation of the crown length of a single tree, taking into account the space it has at its disposal.Položka Mechanochemical synthesis of aromatic ketones: pyrylium tetrafluoroborate mediated deaminative arylation of amides(Royal Society of Chemistry : Cambridge, 2024) Mkrtchyan, Satenik; Shalimov, Oleksandr O.; Garcia, Michael G.; Zapletal, Jiří; Iaroshenko, Viktor O.A new method has been introduced that is able to tackle the complexities of N–C(O) activation in amide moieties through utilization of pyrylium tetrafluoroborate in a mechanochemical setting, where amide bonds undergo activation and subsequent conversion to biaryl ketones. Due to the employment of a mechanochemical setting, the reaction conforms to green chemistry principles, offering an environmentally friendly approach to traditional amide derivatization techniques that rely on transition metals to achieve further functionalization.Položka Mechanochemical trifluoromethoxylation of aryltrimethylammonium triflates, aryldiazonium tetrafluoroborates, and aryl pinacolboranes(Cell Press : Cambridge, 2024) Mkrtchyan, Satenik; Purohit, Vishal; Zapletal, Jiří; Shalimov, Oleksandr O.; Nociarová, Jela; Addová, Gabriela; Filo, Juraj; Garcia, Michael G.; Kupcová, Elena; Benická, Barbora; Iaroshenko, Viktor O.Aryl trifluoromethyl ethers (ArOCF3) are important structural motifs in pharmaceuticals, agrochemicals, and functional materials. However, the methods reported for the efficient synthesis of these scaffolds are extremely underdeveloped and limited. Here, we report a highly efficient mechanochemical approach for the selective transformation of aryltrimethylammonium triflates, aryldiazonium tetrafluoroborates, and aryl pinacolboranes to aryl trifluoromethyl ethers via in situ-generated OCF3 source using triphosgene and Co(II) fluoride (CoF2). The proposed synthetic protocol also shows potential for the selective transformation of other groups such as arylsulfonium and diaryliodonium functionalities. The present trifluoromethoxylation strategy exhibited a broad functional group tolerance and found to be superior over other existing protocols in terms of substrate scope, yields, operational simplicity, and reaction times.Položka Nanocellulose as a reaction media and stoichiometric reagent for FeCl3-mediated reductive functionalization of nitro compounds(The American Chemical Society : Washington, 2024) Mkrtchyan, Satenik; Purohit, Vishal; Zapletal, Jiří; Shalimov, Oleksandr O.; Iaroshenko, Viktor O.Among a wide array of synthetic amides, N-aryl/alkyl amides are an important class of structural motifs having significant importance in pharmaceutical and agrochemical industries. In this regard, a rapid, low-cost, and environmentally friendly synthesis of N-aryl/alkyl amides still remains in a high demand. Herein, we report a convenient route for the mechanochemical synthesis of N-aryl/alkyl amides via FeCl3-catalyzed reductive amidation of nitro compounds, as well as acylation of aliphatic/aromatic amines with carboxylic acids using nanocellulose as the reaction media/stoichiometric reducing agent. The protocol was found to be simple, efficient, and environmentally benign to obtain a diverse array of the respective amides with good to excellent yields. Furthermore, the use of nitro compounds, amines, and carboxylic acids as cheap and readily available starting materials, FeCl3 as a nontoxic catalyst, and nanocellulose as the biodegradable reaction media as well as the stoichiometric reducing agent makes this protocol in the category of a green chemical transformation.Položka One-step Ru-catalyzed conversion of phenolic OH groups to trifluoromethyl under mechanochemical conditions(Cell Press : Cambridge, 2024) Mkrtchyan, Satenik; Jakubczyk, Michał; Sarfaraz, Sehrish; Ayub, Khurshid; Purohit, Vishal; Shalimov, Oleksandr O.; Iaroshenko, Viktor O.Direct and selective transformation of the phenolic hydroxy group in a concise way without prior derivatization is relevant in many industrial processes, particularly late-stage modification of pharmaceuticals and for lignin-material treatment. The introduction of fluorine has a profound impact on the molecular properties of both small molecules and biopolymers. Herein, we report a Ru-catalyzed transformation of phenols into trifluoromethyl-arenes under mechanochemical conditions. The protocol accepts a wide scope of starting materials and allows for gram-scale synthesis in excellent yields. The developed approach may offer an important alternative to known methods in the context of PASE (pot, atom, and step economy) synthesis and, therefore, green chemistry.Položka Ru-catalyzed activation of free phenols in a one-step Suzuki Miyaura cross-coupling under mechanochemical conditions(Royal Society of Chemistry : Cambridge, 2024) Mkrtchyan, Satenik; Jakubczyk, Michał; Sarfaraz, Sehrish; Ayub, Khurshid; Iaroshenko, Viktor O.Activation of phenols by a Ru-catalyst allows for the resulting η5-phenoxo complex to selectively react with a variety of nucleophiles under mechanochemical conditions. Conversion of phenolic hydroxy groups without derivatization is important for late-stage modifications of pharmaceuticals and in the context of lignin-material processing. We present a one-step, Ru-catalyzed cross-coupling of phenols with boronic acids, aryl trialkoxysilanes and potassium benzoyltrifluoroborates under mechano-chemical conditions. The protocol accepts a wide scope of starting materials and allows for gram-scale synthesis in excellent yields. The developed approach constitutes a very interesting and waste-limiting alternative to the known methods.