Chemical record最新文献

The transition metal catalyzed coupling reaction has revolutionized the strategies for forging the carbon-carbon bonds. In contrast to traditional cross-coupling methods using pre-prepared nucleophilic organometallic reagents, reductive coupling reactions for the C−C bonds formation provide some advantages. Because both coupling partners are reduced in the final products using a stoichiometric amount of a reductant, this approach not only avoids the need to use sensitive organometallic species, but also provides an orthogonal and complementary access to classical coupling reaction. Notably, the reductive coupling reactions feature readily available fragments, promote good step economy, exhibit high functional group tolerance and unique chemoselectivity, which have propelled their increasingly popular in the organic synthesis. In recent years, due to the low price, minimal toxicity, and environmentally benign character, iron-catalyzed carbon-carbon coupling reactions have garnered significant attention from the organic synthetic chemists and pharmacologists, especially the iron-catalyzed reductive coupling. This review aims to provide an insightful overview of recent advances in iron-catalyzed reductive coupling reactions, and to illustrate their possible reaction mechanisms.

Industry, agriculture, and a growing population all have a major impact on the scarcity of clean-water. Desalinating or purifying contaminated water for human use is crucial. The combination of thermal membrane systems can outperform conventional desalination with the help of synergistic management of the water-energy nexus. High energy requirement for desalination is a key challenge for desalination cost and its commercial feasibility. The solution to these problems requires the intermarriage of multidisciplinary approaches such as electrochemistry, chemical, environmental, polymer, and materials science and engineering. The most feasible method for producing high-quality freshwater with a reduced carbon footprint is demanding incorporation of industrial low-grade heat with membrane distillation (MD). More precisely, by using a reverse electrodialysis (RED) setup that is integrated with MD, salinity gradient energy (SGE) may be extracted from highly salinized MD retentate. Integrating MD-RED can significantly increase energy productivity without raising costs. This review provides a comprehensive summary of the prospects, unresolved issues, and developments in this cutting-edge field. In addition, we summarize the distinct physicochemical characteristics of the membranes employed in MD and RED, together with the approaches for integrating them to facilitate effective water recovery and energy conversion from salt gradients and freshwater.

A superhydrophobic surface is defined as having a contact angle exceeding 150 °C, indicating a remarkable ability to repel water. Generally, superhydrophobicity originates from the utilization of low-surface-energy materials with unique micro- and nanostructures. Superhydrophobic surfaces have gained considerable recognition and are widely employed in diverse areas for anti-icing, oil-water separation, anticorrosion, self-cleaning, blood-repellent, and antibacterial applications. These surfaces can greatly enhance industrial processes by yielding significant performance improvements. In this review, we introduce the basic theories that provide a foundation for understanding the hydrophobic properties of superhydrophobic surfaces. We then discuss current techniques for fabricating superhydrophobic coatings, critically analyzing their strengths and limitations. Furthermore, we provide an overview of recent progress in the application of superhydrophobic materials. Finally, we summarize the challenges in developing superhydrophobic materials and future trends in this field. The insights provided by this review can help researchers understand the basic knowledge of superhydrophobic surfaces and obtain the latest progress and challenges in the application of superhydrophobic surfaces. It provides help for further research and practical application of superhydrophobic surfaces.

Polycyclic heterocycles are the most common and critical structural motifs found in a variety of natural products, medicines, fertilizers, and advanced materials. Because of their widespread use in biologically active compounds and material chemistry, functionalised dibenzo heterocyclic compounds, especially dibenzofuran, dibenzothiophene, and carbazole derivatives, garnered much attention over time. Scientists are especially interested in elucidating more efficient techniques for developing these industrially essential compounds. Dibenzo-fused heterocycles can rapidly be synthesised using highly efficient transition metal-catalysed strategies as well as by economic metal-free reaction conditions. This review includes a detailed overview of the most recent significant synthetic techniques, both metal-catalysed and metal-free, to produce these industrially significant and medicinally important dibenzo-fused heterocycles.

In this account, we will highlight recent progress in the development of multichannel lanthanide-doped (MC−Ln) nanoprobes for highly efficient serodiagnosis and therapy, with a particular focus on our own work. First, we first provide a classification of the types of MC−Ln nanoprobes based on the contained type and number of signals. The merits of different types of nanoprobes and the reason using lanthanides are elucidated. Then, we provide an overview of the current uses of MC−Ln nanoprobes in serodiagnosis and therapy, focusing on the strategic exploration to improve the diagnostic and therapeutic performance from different perspectives. Finally, we present a prospective outlook on the future development and potential issues of next-generation MC−Ln nanoprobes. We hope that this timely account will update our understanding of MC−Ln and similar nanoprobes for bioapplications and provide helpful references for the state-of-the-art tools for serodiagnosis and therapy.

Unlike fossil fuels, biomass has oxygen amounts exceeding 10 wt%. Hydrodeoxygenation (HDO) is a crucial step in upgrading biomass to higher heating value liquid fuels. Oxygen removal has many challenges due to the complex chemistry and the high reactivity leading to irreversible catalyst deactivation. In this study, the focus is on the catalytic HDO of aromatic oxygen-containing model compounds in biomass: phenols and cresols. In the current work, literature on catalytic HDO of phenols using molecular hydrogen is reviewed, with a focus on non-nickel-based mono- and bi-metallic catalysts, as nickel-based catalysts were reviewed elsewhere. In addition, the catalytic HDO of m-cresol using molecular hydrogen is examined. This review also addresses the use of hydrogen donors for the HDO of phenols and cresols. The operating conditions, catalysts, products, and yields are summarized to find the catalyst with promising activity and high selectivity toward aromatics. A critical review of the reactions that successfully led to HDO is presented and research gaps related to the HDO of phenols and cresols are highlighted. The conclusions provide potential successful catalyst combinations that can be used for HDO of phenols, cresols, and liquid aromatic hydrocarbons.

On May 1, 1965, Roald Hoffmann and R. B. Woodward published their second joint communication, Selection Rules for Concerted Cycloaddition Reactions, in the Journal of the American Chemical Society. Herein is presented a historical analysis of Woodward and Hoffmann's determination of the mechanism of cycloadditions. This analysis is based on thorough analyses with Roald Hoffmann of his 1964 and 1965 laboratory notebooks and his archived documents and on numerous in-person, video, and email interviews. This historical research pinpoints several seminal moments in chemistry and in the professional career of Hoffmann. For example, now documented is the fact that Woodward and Hoffmann had no anticipation that their collaboration would continue after the publication of their first 1965 communication on electrocyclizations. Also pinpointed is the moment in Hoffmann's professional and intellectual trajectories that he became a full-fledged, equal collaborator with Woodward and Hoffmann's transition from a “calculator” to an “explainer.”

Cover Picture: The cover image shows the recommendation of nitrogen circulating based on the development of a catalytic technology to recycle harmful nitrogen oxides (NO_x), that should be purified to N₂ before releasing to the atmosphere but artificially supplied through high-temperature combustion, as nitrogen compounds like valuable ammonia (NH₃), possibly contributing to the sustainability with saving green land and blue sky in future. More details can be found in article number e2024000094 by Tatsuo Kimura (DOl: 10.1002/tcr.202400094.

Pd-catalyzed stereoselective glycosylations using unsaturated sugar derivatives, glycals, have been successfully achieved in recent years. This review focuses on approaches to control the stereoselectivities of glycosides via π-allyl intermediates that mimic the Tsuji–Trost asymmetric allylic alkylation reactions, enabling stereoselectivity control through rational design. In the reaction process, zwitterionic Pd-π-allyl complexes, formed after the oxidative addition and decarboxylation, play a crucial role in increasing reactivities and enhancing the stereoselectivities of α- and β-glycosides. We summarized recently developed Tsuji–Trost type glycosylations using 3,4-carbonate galactals, featuring high efficiency, exclusive stereoselectivities, and a broad reaction scope including O-, N-, S-, and C-glycosylations.

Catalysis has been at the forefront of the developments that has revolutionised synthesis and provided the impetus in the discovery of platform technologies for efficient C−C or C−X bond formation. Current environmental situation however, demands a change in strategy with catalysis being promoted more in solvents that are benign (Water) and for that the development of hydrophilic ligands (especially phosphines) is a necessity which could promote catalytic reactions in water, allow recyclability of the catalytic solutions and make it possible to isolate products using column-free techniques that involve lesser usage of hazardous organic solvents. In this review, we therefore critically analyse such catalytic processes providing examples that do follow the above-mentioned parameter.