Topics in Current Chemistry最新文献

The direct functionalization of unactivated C(sp³)–H bonds is crucial for the synthesis of organic compounds, enabling the efficient generation of C(sp³)–X bonds (X = carbon, heteroatom) in natural products and pharmaceuticals. Despite the natural inertness of these bonds and the challenges associated with regioselectivity in alkanes, various approaches, primarily coordination-assisted and radical methods, have been developed to address these issues and enable effective catalytic activation. This review provides a comprehensive overview of transition-metal-catalyzed direct functionalization of nonactivated C(sp³)–H bonds. It analyzes the literature published since 2021 to showcase the most advanced methods available today and their respective limitations. This review reveals that, during this time, most efforts have concentrated on coordination-assisted methods, whereas fewer radical mechanisms have been investigated for C(sp³)–H bond activation. However, radical mechanisms are important because they often occur under milder conditions and typically use simpler starting materials, which are crucial for our needs. In this review, we divide reactions according to the type of metal employed (Pd, Co, Ni, Fe, Ru, Rh, Ir, or Cu) and then further on the basis of their mechanisms: coordination-assisted transition-metal mechanisms and radical mechanisms. Additionally, we occasionally categorize the reactions of metals on the basis of different directing groups: (i) native directing groups, (ii) exo directing groups, and (iii) traceless directing groups. This review underscores that effectively addressing the challenges associated with C(sp³)–H bond activation, including regioselectivity and the activation of flexible and stable C(sp³)–H bonds, relies on the employment of appropriate ligands in the reactions. The use of these ligands is examined in detail throughout the review.

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The direct functionalization of unactivated C(sp³)−H bonds is crucial for chemical synthesis, enabling the efficient creation of C(sp³)–X bonds (X = carbon, hetroatom) in natural products and pharmaceuticals. However, the inherent inertness of these bonds and regioselectivity issues in alkanes pose significant challenges for effective catalytic systems. In this review, we organize reactions according to the type of metal employed (Pd, Co, Ni, Fe, Ru, Rh, Ir, or Cu) and then further on the basis of their mechanisms: radical mechanisms and coordination-assisted transition-metal mechanisms.

Deuterium is a safe bioisostere of hydrogen, and its selective labeling has a great prominence in medicinal chemistry for the amelioration of the pharmacokinetic profiles of the drugs. The deuterium-labeled pharmaceutically active compounds have been observed to exhibit broad applications, either as deuterated drugs or as pharmacokinetic probes (biomarkers). The deuterated drugs offer improved bioactivity and metabolic profile in terms of tolerability, efficacy, and reduced toxicity. In this manuscript, the synthetic strategies of various deuterated drugs including antiviral, anticancer, antiarrhythmic, antidiabetic, anticholinergic, antibiotics, antidepressants, and antipyretics have been documented. In addition, this review article also comprises a broad class of miscellaneous drugs i.e., antiasthmatic drugs, antiseptics, topical analgesics, antifibrotic agents, immunosuppressants, and central nervous system (CNS) suppressants. Additionally, the synthesis of several deuterated pharmaceutically active compounds as biomarkers has also been compiled in this review. Leveraging the modern platform of precision deuteration, this review article provides a repertoire of synthetic strategies for the synthesis of several deuterated drugs reported over a period of 2005–2024 (two decades).

Aptamers are oligonucleotide sequences selected in vitro that possess advantages such as small size, non-toxicity, and ease of modification. Aptamer-based biosensing is advancing rapidly owing to the high affinity and specificity of aptamers for target molecules. Nevertheless, their relatively flexible structure and susceptibility to degradation in biological environments pose challenges for practical applications. To address these issues, researchers are developing functionally engineered aptamers through structural modifications such as chimera formation and splitting. These advancements have significantly accelerated aptamer research across multiple fields. This review highlights recent progress in functionally engineered aptamers, summarizing their construction strategies and applications in sensing. It also analyzes the characteristics of different types of engineered aptamers and their multi-field applications. Finally, current bottlenecks and future prospects are critically discussed. This review provides a systematic overview of engineered aptamers from a functional perspective, offering valuable insights for ongoing research in this dynamic field.

Patterning techniques have significantly advanced materials science by enabling precise control over structural and functional features of materials. Metal–organic frameworks (MOFs), covalent organic frameworks (COFs), and conjugated polymers possess exceptional properties, including high porosity and tunable surface chemistry, making them promising candidates for patterning strategies. This review examines how these materials can be integrated with photolithography, self-assembly, and direct writing, emphasizing their synthesis, compatibility with fabrication methods, and performance advantages. Potential applications in electronics, optoelectronics, and catalysis are discussed, along with current challenges related to stability, scalability, and device integration. Finally, the review identifies emerging directions for patterning technologies that could drive the next generation of functional devices.

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Ionic liquids (ILs) are unique materials made of cations and anions that have seen a resurgence in recent decades owing to their wide applicability. The utility of ILs in the field of high-energy molecules and energetic materials has been widely studied. These compounds have an enormous reservoir of chemical energy that can be liberated under specified conditions. With increased environmental and safety concerns, much effort has been put into developing ecologically friendly, high-energy molecules. ILs have shown the potential to be one of them. This article covers ILs based on imidazole, triazole, and tetrazole molecules as well as their synthesis, properties as high-energy molecules, and applications.

Triazoles, a captivating class of nitrogen-containing heterocyclic compounds, have emerged as pivotal players in contemporary chemistry, drawing significant attention for their exceptional versatility and wide-ranging applications. They have become essential building blocks in modern chemistry, exhibiting remarkable adaptability in a multiple areas of utility. Artificial intelligence (AI)-driven drug discovery in medicinal chemistry has sped up the process of finding bioactive triazole derivatives with improved therapeutic potential. Green chemistry techniques, such as metal-free protocols, ionic liquid-mediated synthesis, and click chemistry, have transformed their synthesis, which guarantees sustainability, effectiveness, and low environmental impact. Beyond the pharmaceutical industry, triazoles are essential to next-generation material science, helping to create anticorrosion coatings, biosensors, and high-performance solar cells. Their incorporation into organic electronics and nanotechnology has led to revolutionary breakthroughs in several industries by greatly enhancing energy storage systems, protective coatings, and sensor sensitivity. As studies continue, combining artificial intelligence and environmentally friendly synthesis techniques broadens the range of triazole applications, confirming their position as essential facilitators of scientific and technological advancement. These advancements not only streamline the creation of triazole derivatives but also expand the scope of their applications, propelling research and development across multiple domains.

Research on heterocyclic compounds is an area of continuous focus, capturing the interest of both synthetic and natural product chemists. Indazoles are one of the rare heterocycles that are available in nature. Indazole and its derivatives are one of the most important classes of heterocycles in pharmacological molecules. The structurally different indazole motifs, with impressive bioactivity, have drawn increasing attention from medicinal chemists in recent years for the continuous development of novel drug moieties. Thus, knowledge of the biological activities and synthetic pathways of indazole scaffolds is essential to enhancing further developments in the number of indazole-based lead molecules. The goal of the present review is to highlight information on the biological properties of some existing indazole-based drugs and activities of novel bioactive indazole compounds in clinical trails, with specific attention to the most recent advances in various synthetic strategies towards indazole and its derivatives over the past 7 years (2017–2024). Moreover, we discuss the substrate tolerance and mechanistic insights for most of the summarized synthetic protocols.

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Bioorthogonal bond-cleavage reactions have evolved into powerful tools for chemical biology, representing a promising strategy for achieving controlled release of molecules under physiologically relevant conditions, even in living organisms. Since their discovery, significant efforts have been invested in the development and understanding of the underlying chemistries to enhance the click-to-release performance, biocompatibility, and stability of bioorthogonal tools. In this review, we aim to provide a concise overview of click-triggered bioorthogonal bond-cleavage reactions, with an emphasis on the mechanisms and characteristics of the most commonly applied click-to-release chemistries.

This review systematically analyzes recent advances in transition metal-catalyzed carbene and nitrene insertion into unactivated aliphatic C(sp³)–H bonds through inner-sphere mechanisms, offering a critical synthesis of mechanistic insights and synthetic applications from 2016 to 2024. By contrasting inner- and outer-sphere pathways, we elucidate how metal–substrate coordination governs regioselectivity, catalyst design, and substrate compatibility. Key discussions focus on breakthroughs in Rh(III), Pd(II), Co(III), Ir(III), and Ni(II) catalytic systems, emphasizing their distinct electronic and steric control strategies for directing C–H activation and migratory insertion. Notable achievements include the functionalization of sterically hindered substrates, enantioselective aminations via chiral ligand engineering, and cascade transformations enabled by metal-mediated β-elimination. We highlight emerging trends in sustainable catalysis using earth-abundant metals (e.g., Co, Ni), while addressing persistent challenges such as directing group dependency, catalyst deactivation, and limited substrate scope. The review further proposes strategic frameworks for future innovation, including (1) computational ligand optimization to enhance regiochemical control, (2) transient directing group strategies for native functional group tolerance, and (3) bifunctional catalyst design to differentiate electronically equivalent C–H bonds. By bridging mechanistic understanding with practical synthetic goals, this work establishes a roadmap for advancing precision C(sp³)–H functionalization in complex molecule synthesis and industrial applications.

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Spiroethers, a subset of natural and synthetic spirocycles, possess various biological activities. These motifs are found in natural products and exhibit anticancer, antidepressant, antiviral, antimalarial, and antituberculosis properties. Because of their exceptional structures, spiroethers can serve as important bioactive scaffolds in the pharmaceutical industry to improve bioavailability and stability and in drug discovery. Many of these compounds can also be used in perfumes and flavors owing to their olfactory properties. Given the increasing interest in spiroether-derived compounds in the pharmaceutical industry and the low yields of spiroethers provided by natural sources, which are not economically viable for industrial demand, synthetic approaches have garnered significant attention. In this review, we provide insight into 16 different approaches suggested for the synthesis of spiroethers; these methods are classified in the following five categories: catalytic methods (four methods), cyclization reactions (three methods), nucleophilic/electrophilic additions (two methods), functional group transformation (three methods), and miscellaneous (four methods). Certain advantages including material availability, high yield, simple procedures, low cost, ability to enhance biological properties of the final products, and so on are reported for these approaches.