Organic Chemistry Research Articles

Electrochemical Oxidation of UV Filters: A First-Principles Molecular Dynamics Study.

A theoretical model is proposed to study the oxidation mechanisms of the organic UV filters BP3 and BP4 during electrochemical water treatment utilizing Car-Parrinello molecular dynamics. Factors such as the amount of solvent to be included and how to design the system with the least possible intervention are discussed. The proposed model consist of the optimization of the geometries by density functional theory methods, the equilibration of the structure immersed in a water box, the inclusion of the reactive species, and the analysis of the reaction energies of each reaction pathway. The ab-initio molecular dynamics simulations lead to several products, and some trends can be identified, in accordance with the well-known reactivity rules of organic chemistry. The products proposed in this work are intermediates in longer oxidative pathways.

Development and Application of Electromigration Methods at the Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences

Development and Application of Electromigration Methods at the Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences

Aldoxime dehydratases: production, immobilization, and use in multistep processes.

The synthesis of nitriles is of utmost importance for preparative organic chemistry. The classical routes are often associated with disadvantages such as toxicity of the reagents and drastic conditions. The uses of enzymes like aldoxime dehydratases (Oxds) and hydroxynitrile lyases constitute attractive benign alternatives. In this review, we summarize the recent trends regarding Oxds. Thousands of oxd genes were sequenced but less than thirty Oxds were investigated on protein level. We give an overview of these Oxds, their sequence analysis, conditions required for their overexpression, and their purification and assays. We then focus on the use of Oxds especially in multistep reactions combining the chemical or chemoenzymatic synthesis of aldoximes from different starting materials with the enzymatic dehydration of aldoximes to nitriles, possibly followed by the hydration of nitriles to amides. Progress in Oxd immobilization is also highlighted. Based on data published mainly in the last 5years, we evaluate the industrial prospects of these enzyme processes in comparison with some other innovations in nitrile synthesis. KEY POINTS: • Aldoxime dehydratases (Oxds) are promising for cyanide-free routes to nitriles • A comprehensive overview of wet-lab explored Oxds is provided • Recent trends include combining Oxds with other enzymes or chemical catalysts.

How Are The Science Process Skills of Prospective Science Teacher Students: Studies in Inorganic Chemistry and Gender

Prospective teacher students must be able to design practicums so that the learning process is meaningful. The skills that students develop in carrying out scientific discoveries, namely applying concepts, rules, and characteristics that exist in science, are called science process skills (SPS). Therefore, in building students' knowledge, students must have process skills in teaching so they can teach effectively and must have a good understanding of concepts and strong process skills. This research aims to describe the SPS of prospective science education teacher students through inorganic chemistry courses after going through learning with the discovery learning model. This research uses a quantitative approach with a pre-experimental design one-shot case study research method. The research results show that student SPS as a whole is in the high category with an average percentage of 59.71%. SPS analysis in classes A, B, and C, respectively, has an average percentage of 58.23%, 62.66%, and 58.24% in the high category. SPS analysis based on gender shows that the respective percentage of male students is 53.89% with the medium category for women and 59.81% for the high category.

Computational Studies of Molybdenum-Containing Metal–Sulfur and Metal–Hydride Clusters

The development of transition metal clusters is an active area of research in inorganic chemistry, as they can be used as catalysts to perform chemically or biologically relevant reactions. Computational chemistry, employing density functional theory (DFT), plays a key role in rationalizing the electronic structure and properties of transition metal clusters. This article reviews recent quantum chemical studies of Mo3S4M clusters (M = Fe, Co, Ni), their CO- or N2-bound variants, and metal–hydride clusters. The ground state of the cluster systems was computed, and properties such as metal–metal bonding, orbital interactions, fluxional behavior of ligands, spectroscopy, and reaction mechanisms were rationalized and compared with available experimental results. Our research findings evidence that computational studies employing quantum chemical methods can guide experimental researchers to develop novel transition metal clusters for potential applications in catalysis.

Investigation of the interference between organic and mineral matter in coal and carbonaceous shale using FTIR spectroscopy

ABSTRACT Thirty-two coal (lignite-bituminous in rank) and carbonaceous shale samples, ranging from immature to overmature, were collected from the various coal-bearing basins (Saurashtra Basin, Bikaner Nagaur Basin, Damodar Basin, Mahanadi Basin, and Foreland Basin) in India and characterized petrographically (vitrinite reflectance and maceral composition), geochemically (total organic carbon and total sulfur) and chemically (Fourier Transform Infrared spectroscopy, FTIR). This paper explores utilization of FTIR study on bulk non-demineralized carbonaceous shale and coal to examine the interference between mineral and organic matter visible on FTIR spectra and application of such techniques to assess organic matter chemistry based on FTIR signal. Mineral matter is considerably affecting the organic matter FTIR signal in the region between 1700–1350 and 900–700 cm−1, while the 3100–2800 cm−1 region is unaffected. The general trends of organic matter evolution with thermal maturity, i.e. a decrease of aliphatic and oxygen-bearing groups and increase in aromatic signal, are visible in bulk non-demineralized samples; however, the interpretation of the signal is problematic due to the dilution-related signal weakening and region-specific overlapping. The quality of the FTIR signal is lower than the signal from demineralized kerogens or targeted specific maceral grains via combination of FTIR with microscopy. The spectra can still be useful for more qualitative aspects of FTIR, like assessment of organic functional groups, study of coal impurities, or as a complementary method in conjunction with other analytical techniques such as X-ray for mineral matter characterization.

Cobalt-Hydride-Catalyzed Alkene-Carboxylate Transposition (ACT) of Allyl Carboxylates.

The alkene-carboxylate transposition (ACT) of allyl carboxylates is one of the most atom-economic and synthetically reliable transformations in organic chemistry, as allyl carboxylates are versatile synthetic intermediates. Classic ACT transformations, including [3,3]-sigmatropic rearrangement and transition metal-catalyzed allylic rearrangement, typically yield 1,2-alkene/1,3-acyloxy shifted products through a two-electron process. However, position-altered ACT to produce distinct 1,3-alkene/1,2-acyloxy shifted products remains elusive. Here, we report the first cobalt-hydride-catalyzed ACT of allyl carboxylates, enabling access to these unprecedented 1,3-alkene/1,2-acyloxy shifted products via a 1,2-radical migration (RaM) strategy. This transformation demonstrates broad functional group tolerance, is suitable for late-stage modification of complex molecules, and is amenable to gram-scale synthesis. It also expands the reaction profiles of both allyl carboxylates and cobalt catalysis. Preliminary experimental and computational studies suggest a mechanism involving metal-hydride hydrogen atom transfer (MHAT) and the 1,2-RaM process. This reaction is expected to serve as the basis for the development of versatile Co-H-catalyzed transformations of allyl carboxylates, generating a wide array of valuable building blocks for synthetic, medicinal, and materials chemistry.

Dual Benefits of Tirzepatide: Anti-Obesity and Antidiabetic Efficacy: A Mini review

Background: Diabetes mellitus and obesity are two linked conditions that have reached epidemic proportions globally. According to a study published in 2023 by the Indian Council of Medical Research (ICMR) , India has 10.1 crore people with diabetes. The prevalence of obesity, especially abdominal obesity is increasing continuously due to the intake of foods that are high in carbohydrates and processed foods. Obesity can cause inflammation, insulin resistance, and pancreas overload which lead to diabetes mellitus. Main Body: The present - review focuses on the medicinal chemistry, organic chemistry and pharmacological aspects of trizepatide. Trizepatide is a new chemical moiety that shows dual agonist activity of glucagon-like peptide-1(GLP-1) receptors and glucose-dependent insulinotropic polypeptide(GIP).Trizepatide is a synthetic peptide that constitutes 39 amino acids. Trizepatide has a potent hypoglycemic effect , and it has antiobesity effects because of its adverse effect. Conclusion : Trizepatide's capacity to lower blood sugar and promote weight loss makes it an effective treatment for these conditions. Further research will confirm its safety and long-term advantages. Keywords : Trizepatide , Diabetes mellitus , Obesity, Hypoglycaemia

A novel pillar-layered MOF with urea linkers as a capable catalyst for synthesis of new 1,8-naphthyridines via the anomeric-based oxidation.

Metal-based catalysts play an essential role in organic chemistry and the chemical industry. This research designed and successfully synthesized a pillar-layered metal-organic framework (MOF) with the urea linkers, namely Basu-HDI, as a novel and efficient heterogeneous catalyst. Various techniques such as FT-IR, EDX, elemental mapping, SEM, XRD, BET, and TGA/DTA studied its structure and morphology. Then, we investigated the synthesis of new 1,8-naphthyridines utilizing Basu-HDI in mild conditions via a one-pot, three-component tandem Knoevenagel/Michael/ cyclization/anomeric-based oxidation reaction. Final products were achieved by anomeric-based oxidation without employing an oxidation agent. Remarkably, this tandem process gave a good range of new 1,8-naphthyridines with high yields in a short reaction time. The pure products were confirmed by FT-IR, 1H NMR, 13C NMR, and mass spectrometry techniques. Moreover, the introduced catalyst showed good efficiency and stability and can be reused four times without significantly reducing efficiency.

Regioselective Electrochemical Construction of Csp2−Csp2 Linkage at C5−C5’ Position of 2‐Oxindoles via an Intermolecular Anodic Dehydrogenative Coupling

AbstractApplying electricity as a reagent in synthetic organic chemistry has attracted particular attention from synthetic chemists worldwide as an environmentally benign and cost‐effective technique. Herein, we report the construction of the Csp2−Csp2 linkage at the C5−C5’ position of 2‐oxindole utilizing electricity as the traceless oxidant in an anodic dehydrogenative homo‐coupling process. A variety of 3,3‐disubstituted‐2‐oxindoles were subjected to dimerization, achieving yields of up to 70 % through controlled potential electrolysis at an applied potential of 1.5 V versus Ag/Ag+ nonaqueous reference electrode. This electro‐synthetic approach facilitates the specific assembly of C5−C5’ (para‐para coupled) dimer of 3,3‐disubstituted‐2‐oxindole without the necessity of any external oxidants or additives and DFT (Density Functional Theory) calculations provided confirmation of this pronounced regioselectivity. Furthermore, validation through control experiments and voltammetric analyses substantiated the manifestation of radical‐radical coupling (or biradical pathway) for the dimerization process.

Weekly Cumulative Quizzes in Organic Chemistry

Weekly Cumulative Quizzes in Organic Chemistry

Extending access for all chemistry students with extended reality

Equal access to instructor’s time and attention in chemistry classes and laboratories can be a barrier experienced by students from historically excluded groups. An instructor’s own biases will determine the nature of their interaction with students, and even well-meaning instructors can interact with students in slightly different ways, which might prevent certain students from having access to all the available instructional resources for the class. This is an additive problem, which may or may not be recognized in peer and student evaluations, and an issue that might escape self-reflection even in educators that are committed to diversity, inclusion, and justice. This issue conflates both actual and perceived biases, introducing a complex dynamic between instructor and student. Extended reality (XR) provides an avenue to generate materials that can be used to enhance or replace classroom instruction with a great degree of realism. In this paper we will discuss the implementation of a set of virtual reality (VR) organic chemistry labs. We will show that XR learning tools are by their very nature accessible and inclusive of a wide variety of students and will provide evidence from student reflections that shows that students from historically excluded groups find the XR content offered in our virtual reality labs more personal than in-person activities covering the same material.

Investigating chemistry teachers’ technological, pedagogical, and collaborative skills of using web-based discussion tools in teaching organic chemistry in selected Rwandan secondary schools

Investigating chemistry teachers’ technological, pedagogical, and collaborative skills of using web-based discussion tools in teaching organic chemistry in selected Rwandan secondary schools

Strategy for C−H Functionalization of Cubanes: From Stoichiometric Reaction to Catalytic Methodology

AbstractWe summarized a strategy for C−H functionalization of cubanes, highlighting recent progress in the field. Cubane, known as a bioisostere of benzene ring, and its functionalization hold significant potential for future drug development. However, owing to its highly strained and thermodynamically unstable nature, the methodologies are limited and their precise and diverse functionalization is challenging in current organic chemistry. In this Concept, we categorized and explained these methodologies, which represents a majority of current cubane C−H functionalization. In addition, we discussed recent advancements in catalytic C−H functionalization methods, demonstrating their potential to address these challenges effectively.

Computer prediction of toxicity of new S-alkyl derivatives of 1,2,4-triazole

1,2,4-Triazole derivatives are of researchers’ significant interest due to their diverse biological properties, such as antimicrobial, anti-inflammatory, anticancer, and antioxidant activities. The integration of a 2-bromo-4-fluorophenyl fragment into the triazole structure can significantly enhance these activities. However, the evaluation of the toxicity of such compounds remains a critically important aspect for their practical application. To reduce the time and cost of experimental studies, QSAR (Quantitative Structure-Activity Relationship) methods are actively used, allowing the prediction of toxicity based on the molecular structure of compounds. Aim of the study. To assess the toxicity of new S-derivatives of 5-(2-bromo-4-fluorophenyl)-4-R-1,2,4-triazol-3-thiols using the QSAR method, specifically to predict acute toxicity parameters (LD50), and to determine the influence of different (length) radicals on the toxicity of these compounds. Materials and methods. The objects of the virtual study were derivatives of 5-(2-bromo-4-fluorophenyl)-4-ethyl-1,2,4-triazol-3-thiols. They were evaluated at the Department of Toxicological and Inorganic Chemistry of the Zaporizhzhia State Medical and Pharmaceutical University. The toxicity assessment was conducted using the nearest neighbor method via the Toxicity Estimation Software Tool (TEST). The prediction of the lethal dose (LD50) for rats was based on the structural similarity of the studied compounds with known substances, for which experimental toxicity data are available. Results. The conducted QSAR analysis demonstrated that structural changes in S-derivatives of 5-(2-bromo-4-fluorophenyl)-4-ethyl-1,2,4-triazol-3-thiols significantly affect the predicted toxicity. The primary factor influencing the changes in LD50 values is the variation of radicals at the 5th position of the triazole ring. Conclusions. The results of the study showed, that the toxicity of new S-alkyl derivatives of triazol-3-thiols depends on the type of alkyl substituent. Compounds with propyl to heptyl fragments exhibit increased toxicity, while derivatives with thiol, octyl, nonyl, and decyl residues are characterized by lower toxicity.

QSAR prediction of toxicity for a new 1,2,4-triazole derivatives with 2-bromo-5-methoxyphenyl fragment

New derivatives of 1,2,4-triazole are promising research targets due to their unique biological properties, including antimicrobial, antifungal, antitumor, and antioxidant activities. The introduction of the 2-bromo-5-methoxyphenyl fragment into the triazole structure potentially enhances these properties. However, the issue of toxicity for such compounds remains a critical factor for their further application. To reduce experimental costs and time, QSAR (Quantitative Structure-Activity Relationship) methods are widely applied, allowing to predict compounds toxicity based on their molecular structure. The aim of this study was to evaluate the toxicity of new derivatives of 5-(2-bromo-5-methoxyphenyl)-4-R-1,2,4-triazole-3-thiols, their acids, and esters using the QSAR method to predict parameters of acute toxicity (LD50) and to assess the influence of various radicals on the toxicity of the compounds. Materials and methods. The objects of this study were derivatives of 5-(2-bromo-5-methoxyphenyl)-4-R-1,2,4-triazole-3-thiols, synthesized at the Department of Toxicological and Inorganic Chemistry of Zaporizhzhia State Medical and Pharmaceutical University. The nearest neighbor method was used for toxicity evaluation, applying the Toxicity Estimation Software Tool (TEST). The prediction of rats lethal dose (LD50) was based on the structural similarity of the studied compounds with known substances that have experimental toxicity data. Results. The QSAR analysis revealed that structural modifications in the derivatives of 5-(2-bromo-5-methoxyphenyl)-4-R-1,2,4-triazole-3-thiols significantly influence their toxicity. Specifically, increasing the size of the radicals, especially through the introduction of aromatic fragments, contributed to the enhanced safety of the compounds, as evidenced by the increase in LD50 values. The highest LD50 values were observed for compounds containing phenyl radicals. Conclusions. The results of this study indicate the feasibility of using QSAR models to predict the toxicity of 1,2,4-triazole derivatives containing a 2-bromo-5-methoxyphenyl fragment. The observed trend of increasing safety with the introduction of larger aromatic radicals can be used for the rational design of new compounds with improved toxicological properties.

Catalyst-free and wavelength-tuned glycosylation based on excited-state intramolecular proton transfer

The chemoselectivity of organic reactions is a fundamental topic in organic chemistry. In the long history of chemical synthesis, achieving chemoselectivity is mainly limited to thermodynamic conditions by an exogenous activation strategy. Here, we design an endogenous activation method, which can be used to control the chemoselectivity of phenol and naphthol through the photo-induced excited-state intramolecular proton transfer (ESIPT). A wavelength-tuned glycosylation is developed to showcase the penitential of this new strategy. Traditionally, an exogenous activator (electrophilic promoters) is essential to induce the cleave of a polar single bond, and this strategy has been extensively studied and used in the glycosylation chemistry, for the formation of oxocarbenium cation intermediate. In our systems, the oxocarbenium cation intermediates can be selectively formed from glycosyl donors bearing tunable chromophoric groups under mild conditions of acid-base free and redox neutrality, which enables continuous synthesis of oligosaccharides.

Beyond expectations: the development and biological activity of cytokinin oxidase/dehydrogenase inhibitors.

Cytokinins are one of the main groups of plant hormones that regulate growth and development of plants. Cytokinin oxidase/dehydrogenase (CKX) is an enzyme that rapidly and irreversibly degrades cytokinins and thus directly affects their concentration and physiological effect. Genetically modified plants with reduced CKX activity in the shoot, i.e. with a higher concentration of cytokinins, showed e.g. increased tolerance to drought stress, formed larger inflorescences and had higher grain yield. For these reasons, chemical compounds capable of inhibiting the CKX activity (CKX inhibitors) were sought. First, they were identified among strong synthetic cytokinins, but their inhibitory activity was low. The trend has been to develop potent CKX inhibitors with minimal intrinsic cytokinin activity in the hope of avoiding the negative effect of cytokinins on root growth. Cloning CKX, production of key recombinant enzymes from Arabidopsis (AtCKX2) and maize (ZmCKX1 and ZmCKX4a), development of screening bioassays and progress in X-ray crystallography and synthetic organic chemistry led to extensive progress in the development of these compounds. Currently, the most suitable CKX inhibitors are seeking their application in research and the commercial sphere in two main areas - plant tissue cultures and agriculture. The key milestones that preceded it are summarized in this review.

Investigating the Learning Goals and Expectations of Laboratory Coordinators, Graduate Teaching Assistants, and Students in General and Organic Chemistry Laboratory Courses

Investigating the Learning Goals and Expectations of Laboratory Coordinators, Graduate Teaching Assistants, and Students in General and Organic Chemistry Laboratory Courses

Exceptions, Paradoxes, and Their Resolutions in Chemical Reactivity.

Progress in chemistry has primarily been framed through inductive processes, leading to the frequent emergence of exceptions and unexpected reactivities. These anomalies─ranging from surprising reactivity trends and paradoxical understandings to unanticipated parameter influences and unexpected successes or failures in synthetic methods─offer valuable insights that can drive scientific discovery. While it is commonly accepted that such exceptions can drive progress, many have been passively accepted without being explored for opportunities. Although numerous chemists have addressed exceptions and refined chemical models and theories, employing a systematic framework for actively exploring and understanding the underlying causes of exceptions could resolve paradoxes in broader contexts and create a greater impact than treating anomalies as isolated occurrences. This perspective demonstrates a proactive epistemic approach to uncovering the opportunities presented by exceptions and promotes deliberate, thoughtful engagement with paradoxes and anomalies. While the examples primarily focus on physical organic chemistry, the concepts are broadly applicable across various fields in chemical science. The thinking framework presented here is neither exhaustive nor prescriptive, but it outlines one of many potentially possible ways to inspire further development in how these anomalies could be harnessed for advancement.