Chemical record最新文献

Ammonia is a key chemical in the production of fertilizers, refrigeration and an emerging hydrogen-carrying fuel. However, the Haber-Bosch process, the industrial standard for centralized ammonia production, is energy-intensive and indirectly generates significant carbon dioxide emissions. Electrochemical nitrogen reduction offers a promising alternative for green ammonia production. Yet, current reaction rates remain well below economically feasible targets. This work examines the application of electrochemical microfluidics for the enhancement of the rates of electrochemical ammonia synthesis. The review is built on the introduction to electrochemical microfluidics, corresponding cell designs, and the main applications of microfluidics in electrochemical energy conversion/storage. Based on recent advances in electrochemical ammonia synthesis, with an emphasis on the critical role of robust experimental controls, electrochemical microfluidics represents a promising route to environmentally friendly, on-site and on-demand ammonia production. This review aims to bridge the knowledge gap between the disciplines of electrochemistry and microfluidics and promote interdisciplinary understanding and innovation in this transformative field.

Owing to their wide utilizations in synthesis and their products prevalence in numerous natural products, pharmaceuticals and functional materials, the alkene difunctionalization methods for the selective transformations of the olefins are important and have attracted much attention form the synthetic chemists. Among them, the electrochemical alkene difunctionalization reaction is particularly promising and has becoming a potent and sustainable tool for the selective transformations of alkenes into vicinal difunctionalized structures in organic synthesis through simultaneous incorporation of two functional groups. Herein, we summarize recent progress in the electrochemical alkene difunctionalization reactions according to the alkene difunctionalization types as well as the category of the radicals over the past five years. By selecting the remarkable synthetic examples, we have elaborately discussed the substrate scope and the mechanisms for the electrochemical olefin difunctionalization reaction.

Since the introduction of the concept of inherent chirality by Böhmer, an important part of research focused on the asymmetric synthesis of calixarene macrocycles. However, long synthetic procedures and tedious separation strategies hampered the application of this technology in many topics of organic chemistry, including enantioselective molecular recognition and catalysis. Very recently, a new generation of enantioselective catalytic methodologies has been reported, able to provide highly functionalized, inherently chiral calixarenes in a straightforward manner. In this review, we will discuss these new catalytic methods and the versatile properties of such macrocycles that call for potential applications in many areas of science.

In recent times, chemical looping offered a sustainable alternative for upgrading light hydrocarbons into olefins. Olefins are valuable platform chemicals that are utilized for diverse applications. To close the wide shortfall in their global supply, intensified efforts are ongoing to develop on-purpose production technologies. Herein, we provide discussions on the emerging olefin production routes and chemical looping as a frontier concept in catalytic production of chemicals, especially light olefins. Moreover, we discuss the various rational strategies for designing and tuning of oxygen carriers with high catalytic activity and tailored selectivity to desired products. These strategies include creation of oxygen vacancies, controlled doping, synergistic metal-support interactions, regulating oxygen mobility, modulation of crystal structure, functionalization and controlled treatment. The insights presented aim to inspire the development of robust, stable, and efficient oxygen carriers, ensuring catalytic activity, selectivity, and prolonged operational stability.

This paper emphasizes the critical role of electrolyte selection in enhancing the electrochemical performance of nonaqueous Li-O₂ batteries (LOBs). It provides a comprehensive overview of various electrolyte types and their effects on the electrochemical performance for LOBs, offering insights for future electrolyte screening and design. Despite recent advancements, current electrolyte systems exhibit inadequate stability, necessitating the urgent quest for an ideal nonaqueous electrolyte. Such an electrolyte should demonstrate superior physicochemical and electrochemical stability, particularly in the presence of superoxide radicals (O₂ ^-), with high oxygen solubility, rapid diffusion rates, and the capability to form a stable SEI film on the lithium anode. The paper advocates for further research in three key areas: the selection of suitable electrolytes, the construction of stable electrode/electrolyte interfaces, and the mechanistic exploration of byproduct formation. Addressing these challenges will advance the development of electrolyte technology for LOBs, paving the way for its commercialization and broad application.

Front Cover: This cover illustrates the six key stages of carbon capture technology, progressing from material design to technology deployment. Central to the design is a carbon dioxide molecule encircled by an arrow, symbolizing the pursuit of a circular economy. The artwork highlights integrating scientific fundamentals with practical implementation, underscoring the pathway toward sustainable carbon management solutions. More details can be found in the article number e202400188 by Mahmoud M. Abdelnaby and co-workers. (DOI: 10.1002/tcr.202400188).

Cover Feature: The 1,2,4-triazole nucleus is highly prominent due to its versatility in various fields. This AZA-heterocycle acts as an organocatalyst in diverse reactions and as a key scaffold in synthesizing pharmaceuticals, advanced materials (such as energetic compounds), and agrochemicals, underscoring its significant industrial and scientific importance. More details can be found in the article number e202400190 by Anna Claudia Cunha and co-workers. (DOl: 10.1002/tcr.202400190.

Direct methane to methanol conversion is a dream reaction in industrial chemistry, which takes inspiration from the biological methanol production catalysed by methane monooxygenase enzymes (MMOs). Over the years, extensive studies have been conducted on this topic by bioengineering the MMOs, and tailoring methods to isolate the MMOs in the active form. Similarly, remarkable achievements have been noted in other methane activation strategies such as the use of heterogeneous catalysts or molecular catalysts. In this review, we outline the methane metabolism performed by methanotrophs and detail the latest advancements in the active site structures and catalytic mechanisms of both types of MMOs. Also, recent progress in the bioinspired approaches using various heterogeneous catalysts, especially first-row transition metal zeolites and the mechanistic insights are discussed. In addition, studies using molecular complexes such as "Periana catalyst" for methane to methanol conversion through methyl ester formation in the presence of strong acids are also detailed. Compared to the progress noted in the metal zeolites-mediated methane activation field, the utilisation of molecular catalysts or MMOs for this application is still in its nascent phase and further research is required to overcome the limitations of these methods effectively.

Selectfluor, [1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate)], is a highly valuable reagent in contemporary chemistry, serving not only as an electrophilic fluorinating agent but also as an effective catalyst in the synthesis of various pharmaceutically relevant heterocycles. This review article seeks to present a comprehensive overview of the significant heterocyclic ring formations facilitated by selectfluor. Both metal-free and metal-catalyzed recent advancement on selectfluor mediated cyclisation processes are discussed in this review mainly over last eight years (2017-April 2024).

Target identification is crucial for drug screening and development because it can reveal the mechanism of drug action and ensure the reliability and accuracy of the results. Chemical biology, an interdisciplinary field combining chemistry and biology, can assist in this process by studying the interactions between active molecular compounds and proteins and their physiological effects. It can also help predict potential drug targets or candidates, develop new biomarker assays and diagnostic reagents, and evaluate the selectivity and range of active compounds to reduce the risk of off-target effects. Chemical biology can achieve these goals using techniques such as changing protein thermal stability, enzyme sensitivity, and molecular structure and applying probes, isotope labeling and mass spectrometry. Concurrently, computational biology employs a diverse array of computational models to predict drug targets. This approach also offers innovative avenues for repurposing existing drugs. In this paper, we review the reported chemical biology and computational biology techniques for identifying different types of targets that can provide valuable insights for drug target discovery.