Prehliadanie podľa Autor "Sarfaraz, Sehrish"
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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 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.