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This report outlines the evolution and recent progress about the different protocols to synthesize the N‐heterocycles fused hybrids, specifically [1,2,3]triazolo[1,5‐a]quinoline. This review encompasses a broad range of approaches, describing several reactions for obtaining this since, such as dehydrogenative cyclization, oxidative N−N coupling, Dieckmann condensation, intramolecular Heck, (3+2)‐cycloaddition, Ullman‐type coupling and direct intramolecular arylation reactions. We divided this review in three section based in the starting materials to synthesize the target [1,2,3]triazolo[1,5‐a]quinolines. Starting materials containing quinoline or triazole units previously formed, as well as starting materials which both quinoline and triazole units are formed in situ. Different methods of obtaining are described, such as metal‐free or catalyzed conditions, azide‐free, using conventional heating or alternative energy sources, such as electrochemical and photochemical methods. Mechanistic insights underlying the reported reactions were also described in this comprehensive review. [ABSTRACT FROM AUTHOR]

Atropisomeric compounds have been discovered in pharmaceuticals and materials science, and their enantioselective syntheses have gained tremendous attention. Among strategies for catalytic atroposelective synthesis, desymmetrization provides robust and straightforward approaches to axially chiral biaryls. Due to the relative ease of substrate design compared to other atroposelective strategies, desymmetrization has emerged as a pivotal stage for converting fascinating chemistry into its atroposelective counterpart, despite challenges such as the formation of achiral products by subsequent catalytic reactions and the long distance between the reaction site and the stereogenic axis. This review offers a comprehensive overview of recent advancements in atroposelective desymmetrization using chiral organo‐ and metal catalysts, addressing challenges and solutions, and aims to provide insights into future developments in this field. [ABSTRACT FROM AUTHOR]

The combination of metal‐based homogeneous and heterogeneous catalysts in the same reaction media is a powerful, yet relatively unexplored approach in organic chemistry. This strategy can address important limitations associated with purely homogeneous or heterogeneous catalysis such as the incompatibility of different catalytic species in solution, or the limited tunability of solid catalysts, respectively. Moreover, the facile reusability of the solid catalyst, contributes to increase the overall sustainability of the process. As a result, this semi‐heterogeneous multi‐catalytic approach has unlocked significant advances in organic chemistry, improving existing reactions and even enabling the discovery of novel transformations, exemplified by the formal alkane metathesis. This concept article aims to showcase the benefits of this strategy through the exploration of diverse relevant examples from the literature, hoping to spur research on new metal‐based homogeneous‐heterogeneous catalyst combinations that will result in reactivity challenging to achieve by conventional homogeneous or heterogeneous catalysis alone. [ABSTRACT FROM AUTHOR]

This paper introduces a novel method for preparing high-performance, metal-containing carbon foam wave-absorbing materials. The process involves foaming glucose through catalysis by transition metals followed by high-temperature pyrolysis. The resulting carbon foam materials exhibit a highly porous structure, which is essential for their wave-absorption properties. Notably, at a thickness of 2.0 mm, the glucose-derived carbon foam composite catalyzed by Fe and Co (GCF-CoFe) achieved a minimum reflection loss (RLmin) of −51.4 dB at 15.11 GHz, along with an effective absorption bandwidth (EAB) of 5.20 GHz, spanning from 12.80 GHz to 18.00 GHz. These impressive performance metrics indicate that this approach offers a promising pathway for developing low-density, efficient carbon foam materials for wave-absorption applications. This advancement has significant implications for fields requiring effective electromagnetic interference (EMI) shielding, stealth technology, and other related applications, potentially leading to more efficient and lightweight solutions. [ABSTRACT FROM AUTHOR]

This article provides a comprehensive overview of various methods for the synthesis of substituted naphthalene derivatives. Naphthalene is a versatile organic compound with applications in materials chemistry, electronics, and medicine. The synthesis of naphthalene involves metal-catalyzed reactions, such as palladium-catalyzed carboannulation, and yields derivatives with diverse substituents. These derivatives have medicinal importance and exhibit a wide range of therapeutic activities. The article discusses different metal-catalyzed reactions, their mechanisms, and examples of reactions. It also highlights the need for more environmentally friendly approaches to naphthalene synthesis. [Extracted from the article]

This article provides a comprehensive review of recent advancements in the synthesis of tetrahydroindole compounds, which are important for natural alkaloids and synthetic medications. The authors discuss various methods for synthesizing these compounds, including intramolecular cyclization reactions and intermolecular condensations. They highlight the advantages of these methods, such as high yields, shorter reaction times, and low cost of reagents. The authors also identify areas for further development, particularly in the functionalization of the indole benzene ring. [Extracted from the article]

Abstract Cancer has always posed a significant threat to human health, prompting extensive research into new treatment strategies due to the limitations of traditional therapies. Starvation therapy (ST) has garnered considerable attention by targeting the primary energy source, glucose, utilized by cancer cells for proliferation. Glucose oxidase (GOx), a catalyst facilitating glucose consumption, has emerged as a critical therapeutic agent for ST. However, mono ST alone struggles to completely suppress tumor growth, necessitating the development of synergistic therapy approaches. Metal catalysts possess enzyme-like functions and can serve as carriers, capable of combining with GOx to achieve diverse tumor treatments. However, ensuring enzyme activity preservation in normal tissue and activation specifically within tumors presents a crucial challenge. Nanodelivery systems offer the potential to enhance therapy effectiveness by improving the stability of therapeutic agents and enabling controlled release. This review primarily focuses on recent advances in the mechanism of GOx combined with metal catalysts for synergistic tumor therapy. Furthermore, it discusses various nanoparticles (NPs) constructs designed for synergistic therapy in different carrier categories. Finally, this review provides a summary of GOx-metal catalyst-based NPs (G-M) and offers insights into the challenges associated with G-M therapy, delivery design, and oxygen (O2) supply.

Benzo‐fused five‐membered N/O/S heterocyclic compounds, such as indole, benzofuran, and benzothiophene, possessing a single heteroatom, have important applications in medicinal chemistry, agrochemistry, and material chemistry. Metal‐catalysed reactions are well‐established synthetic pathways for the formation of C−X bonds, enabling the direct synthesis of heterocycles. This approach offers advantages over traditional methods, such as fewer steps, increased atom economy, low catalyst loading, regioselectivity, and stereoselectivity. Due to their widespread use in the pharmaceutical industry, the formation of C−N, C−O, and C−S bonds has gained significant attention. This article focusses on the metal‐catalysed synthesis and corresponding mechanistic approaches for N/O/S‐heterocycles, particularly indole, benzofuran, and benzothiophene, reviewing the progress of the past five years and discussing unexplored future opportunities. [ABSTRACT FROM AUTHOR]

α-Substituted-7-azaindoline amides and α,β-unsaturated 7-azaindoline amides have emerged as new versatile synthons for various metal-catalyzed and organic-catalyzed asymmetric reactions, which have attracted much attention from chemists. In this review, the progress of research on 7-azaindoline amides in the asymmetric aldol reaction, the Mannich reaction, the conjugate addition, the 1,3-dipole cycloaddition, the Michael/aldol cascade reaction, aminomethylation and the Michael addition-initiated ring-closure reaction is discussed. The α-substituted-7-azaindoline amides, as nucleophiles, are classified according to the type of α-substituted group, whereas the α,β-unsaturated 7-azaindoline amides, as electrophiles, are classified according to the type of reaction. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Knowledge of asymmetric catalytic reaction mechanism is very important for rational design and synthesis of new chiral catalysts or catalytic systems with high catalytic activity and stereoselectivity. The studies of nonlinear effect have attracted wide attentions as a simple and practical mechanistic tool to probe complex asymmetric catalytic reactions. This review documents the application of the study of nonlinear effects on how to reveal the mechanism in asymmetric catalytic reactions that were catalyzed by the first‐row transition‐metals in the last decade and gives a brief discussion on the different models of nonlinear effect. [ABSTRACT FROM AUTHOR]

The use of energetic nanoparticles to tailor the properties of a base liquid fuel has attracted attention due to the possibility of decreasing fuel consumption and increasing control over the combustion process. In this study, the role of nanomaterials in the consumption of hydrocarbon fuel vapor is investigated using reactive molecular dynamics. Simulations are performed with aluminum and iron nanoparticles inside an n-heptane and oxygen gas mixture. The role of atomic charges on the dynamics of nanoparticle-hydrocarbon interactions is also investigated using different charge equilibration methods. Results show that both nanomaterials act as catalysts and enhance fuel decomposition. The decomposition of fuel molecules is initiated by dehydrogenation at the particle's surface. This reaction path occurs significantly faster than the oxidation and pyrolysis paths observed for n-heptane in absence of nanoparticles. The oxidation in the presence of aluminum is characterized by more rapid particle heating and fragmentation compared to iron. Metal fragments further enhance the reactivity of the system due to a higher surface area available for reactions. The atomic charge distribution was found to affect the kinetics and reactivity of the system, showing that the non-bonded interactions influence the oxidation process. This study confirms that the use of nanomaterials is beneficial to accelerate the decomposition of fuel and that the combustion behavior of the selected hydrocarbon is strongly dependent on the type of nanomaterial used in combination with the base fuel. [ABSTRACT FROM AUTHOR]

Cancer has always posed a significant threat to human health, prompting extensive research into new treatment strategies due to the limitations of traditional therapies. Starvation therapy (ST) has garnered considerable attention by targeting the primary energy source, glucose, utilized by cancer cells for proliferation. Glucose oxidase (GOx), a catalyst facilitating glucose consumption, has emerged as a critical therapeutic agent for ST. However, mono ST alone struggles to completely suppress tumor growth, necessitating the development of synergistic therapy approaches. Metal catalysts possess enzyme-like functions and can serve as carriers, capable of combining with GOx to achieve diverse tumor treatments. However, ensuring enzyme activity preservation in normal tissue and activation specifically within tumors presents a crucial challenge. Nanodelivery systems offer the potential to enhance therapy effectiveness by improving the stability of therapeutic agents and enabling controlled release. This review primarily focuses on recent advances in the mechanism of GOx combined with metal catalysts for synergistic tumor therapy. Furthermore, it discusses various nanoparticles (NPs) constructs designed for synergistic therapy in different carrier categories. Finally, this review provides a summary of GOx-metal catalyst-based NPs (G-M) and offers insights into the challenges associated with G-M therapy, delivery design, and oxygen (O2) supply. [ABSTRACT FROM AUTHOR]

The utilization of CO2 as an efficient and environmentally friendly chemical analogue of CO is becoming a solid reality in the chemical scenario. CO2‐based carbonylations have started paralleling the more consolidated carboxylation procedures, opening new horizons and perspectives in the utilization of carbon dioxide as an organic C1‐containing building block. The advent of efficient and site‐selective metal‐catalyzed protocols for the fixation of CO2 into organic scaffolds, under controlled reductive conditions, contributed substantially to the development of robust, efficient, and convenient protocols. In the present Review article, a collection of the most recent examples of metal‐catalyzed CO2‐based carbonylations is documented with a particular emphasis on mechanistic aspects. [ABSTRACT FROM AUTHOR]

Glycosyl radical functionalization is one of the central topics in synthetic carbohydrate chemistry. Recent advances in metal‐catalyzed cross‐coupling chemistry and metallaphotoredox catalysis provided powerful platforms for glycosyl radical diversification. In particular, the discovery of new glycosyl radical precursors in conjunction with these advanced reaction technologies have significantly expanded the space for glycosyl compound synthesis. In this Review, we highlight the most recent progress in this area starting from 2021, and the reports included will be categorized based on different reaction types for better clarity. [ABSTRACT FROM AUTHOR]

Quaternary stereogenic centers are of great importance because of their prevalence in a series of bioactive natural products and pharmaceuticals. Although the catalytic asymmetric construction of these highly congested centers poses a formidable challenge, this field has been extensively explored in the past few decades, and several elegant strategies, such as the asymmetric conjugate addition to β,β‐disubstituted nitroalkenes, have been developed. The resultant β‐nitro quaternary stereocenters can be conveniently transformed into the corresponding β‐amino quaternary stereocenters commonly found in bioactive compounds. This review summarizes the recent advances in the construction of all‐carbon quaternary or hetero‐carbon quaternary stereocenters via metal‐catalyzed and organocatalyzed asymmetric conjugate addition to β,β‐disubstituted nitroalkenes, focusing on the scope, applications, and mechanisms of these reactions. [ABSTRACT FROM AUTHOR]

Polymersome nanoreactors that can be employed as artificial organelles have gained much interest over the past decades. Such systems often include biological catalysts (i.e., enzymes) so that they can undertake chemical reactions in cellulo. Examples of nanoreactor artificial organelles that acquire metal catalysts in their structure are limited, and their application in living cells remains fairly restricted. In part, this shortfall is due to difficulties associated with constructing systems that maintain their stability in vitro, let alone the toxicity they impose on cells. This study demonstrates a biodegradable and biocompatible polymersome nanoreactor platform, which can be applied as an artificial organelle in living cells. The ability of the artificial organelles to covalently and non‐covalently incorporate tris(triazolylmethyl)amine‐Cu(I) complexes in their membrane is shown. Such artificial organelles are capable of effectively catalyzing a copper‐catalyzed azide‐alkyne cycloaddition intracellularly, without compromising the cells' integrity. The platform represents a step forward in the application of polymersome‐based nanoreactors as artificial organelles. [ABSTRACT FROM AUTHOR]

N−O σ bonds containing compounds are versatile substrates for organic synthesis under transition metal catalysis. Their ability to react through both polar (oxidative addition, formation of metallanitrene, nucleophilic substitution) and radical pathways (single electron transfer, homolytic bond scission) have triggered the development of various synthetic methodologies, particularly toward synthesizing nitrogen‐containing compounds. In this review, we discuss the different modes of activation of N−O bonds in the presence of transition metal catalysts, emphasizing the experimental and computational mechanistic proofs in the literature to help to design new synthetic pathways toward the synthesis of C−N bonds. [ABSTRACT FROM AUTHOR]

The alkali metal tert‐butoxides have found wide application as catalysts and activators for the conversion of numerous organic molecules. These formidable additives in catalytic amounts are extensively employed in the transition metal‐free approaches to serve for the single‐electron transfer processes towards the formation of C−C and C‐heteroatom bond formation. This review elucidates their multifaceted roles encompassing a series of novel synthetic methodologies, in‐depth analyses of their reactivity patterns, and catalytic efficiencies across a myriad of reactions. The involvement of alkali metal tert‐butoxides either directly or in combination with other metals as catalysts are discussed along with the detailed mechanistic pathways in various reactions. Overall, this article summarises approximately all reactions those have been influenced by the catalytic amounts of tert‐butoxides and reported in the last decades. [ABSTRACT FROM AUTHOR]

The catalytic methodologies for the derivatization of aza‐QM have recently appeared in the literature and involve organocatalytic and organometallic approaches. This review aims at analyzing the diverse catalytic systems involving chiral NHC carbenes, phosphoric acids, phosphoramidites, phosphine and copper and palladium catalysis showing its applicability for the synthesis of a diverse away of N‐containing compounds which in many cases have biological activity. [ABSTRACT FROM AUTHOR]

Hydrothermal systems are areas in which heated fluids and organic molecules rush through basaltic material rich in metals and minerals. By studying malononitrile and acetonitrile, we examine the effects of metal and mineral nanoparticles on nitrile compounds in anoxic, hydrothermal conditions representing a prebiotic environment of early Earth. Polymerization, reduction, cyclization, and a phenomenon colloquially known as 'chemical gardening' (structure building via reprecipitation of metal compounds or complexing with organics) are all potential outcomes with the addition of metals and minerals. Reduction occurs with the addition of rhodium (Rh) or iron (II) sulfide (FeS), with positive identification of ethanol and ethylamine forming from acetonitrile reduction. We find that polymerization and insoluble product formation were associated with oxide minerals, metallic nickel (Ni), and metallic cobalt (Co) acting as catalysts. Oxide minerals strongly promoted polymerization into insoluble, tar-like products of nitriles. FeS, iron-nickel alloy (FeNi), and rhodium are unique cases that appear to act as reagents by actively participating in chemical gardening without returning to their initial state. Further, FeS tentatively had a phase change into the mineral parabutlerite. This research aims to identify metals and metal minerals that could best serve nitrile catalysis and reactions on early Earth. [ABSTRACT FROM AUTHOR]

Sequential reactions of aminoalkynes represent a powerful tool to easily assembly biologically important polyfunctionalized nitrogen heterocyclic scaffolds. Metal catalysis often plays a key role in terms of selectivity, efficiency, atom economy, and green chemistry of these sequential approaches. This review examines the existing literature on the applications of reactions of aminoalkynes with carbonyls, which are emerging for their synthetic potential. Aspects concerning the features of the starting reagents, the catalytic systems, alternative reaction conditions, pathways and possible intermediates are provided. [ABSTRACT FROM AUTHOR]

In this short review, we describe applications of hypervalent iodine reagents for the azidation of organic compounds from seminal publications to the most recent reports. After reviewing selected examples of azidations based on the use of in situ formed unstable non-cyclic reagents, we focus in more detail on stable cyclic hypervalent iodine reagents. Important advances in the azidation of C–H bonds, alkenes, as well as other transformations are described. Rather than being comprehensive, we highlight selected key reports that, in our opinion, especially contributed to the advancement of research in the field. 1 Introduction 2 Non-Cyclic λ3-Iodanes 3 Heterocyclic λ3-Iodanes 3.1 Azidation of Aliphatic C–H Bonds 3.2 Azidation of Alkenes 3.3 Other Azidations 4 Conclusion and Outlook [ABSTRACT FROM AUTHOR]

The carbon–nitrogen bond is one of the most prevalent chemical bonds in natural and artificial molecules, as many naturally existing organic molecules, pharmaceuticals, agrochemicals, and functional materials contain at least one nitrogen atom. Radical decarboxylative carbon–nitrogen bond formation from readily available carboxylic acids and their derivatives has emerged as an attractive and valuable tool in modern synthetic chemistry. The promising achievements in this research topic have been demonstrated via utilizing this strategy in the synthesis of complex natural products. In this review, we will cover carbon–nitrogen bond formation via radical decarboxylation of carboxylic acids, Barton esters, MPDOC esters, N–hydroxyphthalimide esters (NHP esters), oxime esters, aryliodine(III) dicarboxylates, and others, respectively. This review aims to bring readers a comprehensive survey of the development in this rapidly expanding field. We hope that this review will emphasize the knowledge, highlight the proposed mechanisms, and further disclose the fascinating features in modern synthetic applications. [ABSTRACT FROM AUTHOR]

5‐hydroxymethylfurfural (HMF), one of the most significant biomass‐derived renewable resources, has been widely utilized to create furan‐based value‐added chemicals such as 2,5‐diformylfuran (DFF), 5‐hydroxymethyl‐2‐furancarboxylic acid (HMFCA), 5‐formyl‐2‐furancarboxylic acid (FFCA), and 2,5‐furan dicarboxylic acid (FDCA). Indeed, DFF, HMFCA and FFCA are key intermediate products during the oxidation of HMF to FDCA. Herein, this review aims to demonstrate the recent advances in metal‐catalyzed oxidation of HMF into FDCA via two different reaction routes (HMF‐DFF‐FFCA‐FDCA and HMF‐HMFCA‐FFCA‐FDCA). All the four furan‐based compounds are comprehensively discussed by the selective oxidation of HMF. Additionally, various metal catalysts, reaction conditions, and reaction mechanisms used to obtain the four different products are systematically reviewed. It is anticipated that this review will provide related researchers with new perspectives and speed up the development of this field. [ABSTRACT FROM AUTHOR]

Sulfur poisoning is a major challenge in catalytic processes where it can result in a gradual decline in the activity of the metal catalyst or a complete deactivation of the catalyst. Many studies were conducted to investigate the effects of sulfur poisoning on metals and address this challenge by developing a catalyst that is resistant to sulfur poisoning without compromising its performance. Boron doping showed to be a promising approach to modify the properties of metal catalysts and improve their performance in various applications. In this work, periodic density functional theory (DFT) calculations were conducted to study boron doping on a number of metals and its impact on sulfur poisoning. The DFT calculations show that boron doping impacts metals differently. Boron doping is favourable on few metals (Pd, Pt, Rh and Ru) and very unfavourable on other metals (e. g. Ag and Cu). On Pd, Pt and Rh, boron doping has a positive impact on reducing sulfur poisoning, with the impact varying with boron concentration. Finally, as a case study, the impact of boron doping on H2S splitting to create H2 was examined and boron doping was shown to have a positive impact on the performance of Pd‐based catalyst. [ABSTRACT FROM AUTHOR]

Chiral primary amines widely exist in drugs and are exceptionally important subunits or synthons in the syntheses of chiral secondary and tertiary amines of medicinal interest. Metal-catalyzed enantioselective reductive amination (ERA) of ketones with ammonium salts or ammonia provides a direct method for their synthesis. Although very useful, progress in this field has been very slow and important advances have only been achieved in the last few years. Several major challenges exist in this reaction, including (1) the reversible formation of unstable NH-imine intermediates; (2) the strong coordination property of N-containing reagents toward metal species; and (3) the lack of efficient catalytic systems that enable high enantiocontrol. Generally, the efficiency and enantiocontrol of this reaction is dependent on the substrate type, for instance, the use of α-keto esters/amides or aryl alkyl ketones is well established and they have even been used in the industrial production of chiral amine drugs. However, highly enantioselective control in dialkyl ketones, cyclic ketones, and α-keto acids remains unsolved. Herein, the historical development of ERA reactions with ammonium salts or ammonia gas is summarized, and novel synthetic applications toward useful synthons or drugs are presented. In addition, the factors restricting the growth of this method are also discussed. 1 Introduction 2 Enantioselective Reductive Amination via Hydrogenation 2.1 Enantioselective Reductive Amination of β-Keto Esters/Amides 2.2 Enantioselective Reductive Amination of Simple Ketones 2.3 Enantioselective Reductive Amination of α-Functionalized Ketones 2.4 Enantioselective Reductive Amination/Cyclization Cascade Reactions 2.5 Others 3 Enantioselective Reductive Amination via Transfer Hydrogenation 4 Synthetic Applications 5 Conclusions and Outlook [ABSTRACT FROM AUTHOR]

Asymmetric oxidation reaction is one of the significant pathways in stereoselective reactions, which is a prominent performer in academic and industrial research. However, ligands are vital for planning an ideal metal‐catalyzed asymmetric oxidation reaction as they interact with the metal to construct catalytically active metal complexes, which can catalyze numerous asymmetric reactions. Designing and synthesizing novel chiral ligands is essential for researchers in modern asymmetric synthesis. In this course, exploring the applicability and the survey of hydroxamic acid as a vital ligand has been presented, which is essential for various metal‐catalyzed transformations. [ABSTRACT FROM AUTHOR]

Abstract Background The combination of metal-catalyzed reactions and enzyme catalysis has been an essential tool for synthesizing chiral pharmaceutical intermediates in the field of drug synthesis. Metal catalysis commonly enables the highly efficient synthesis of molecular scaffolds under harsh organic conditions, whereas enzymes usually catalyze reactions in mild aqueous medium to obtain high selectivity. Since the incompatibility between metal and enzyme catalysis, there are limitations on the compatibility of reaction conditions that must be overcome. Findings We report a chemoenzymatic cascade reaction involved Palladium (Pd) catalyzed Suzuki–Miyaura coupling and whole-cell catalyzed C = O asymmetric reduction for enantioselective synthesis of value-added chiral alcohol. The cell membrane serves as a natural barrier can protect intracellular enzymes from organic solvents. Conclusions With dual advantages of cascade catalysis and biocompatibility, our work provides a rational strategy to harvest chiral alcohols in high yield and excellent enantioselectivity, as a channel to establish chemoenzymatic catalysis.

The construction of C(sp³)-P bonds is of paramount importance in organic synthesis, catalysis, and materials science. Organophosphorus compounds containing C(sp³)-P bonds serve as pivotal structural motifs in ligands, pharmaceuticals, agrochemicals, and functional materials. While traditional methods for C(sp³)-P bond formation largely rely on nucleophilic substitution or coupling of reactive organometallic reagents, recent years have witnessed significant advancements in metal-catalyzed approaches. This review highlights the recent developments in C(sp³)-P bond formation enabled by metals including Cu, Fe, Bi, Pd, Ni, Ru, Rh, and Co, with particular emphasis on methodologies that activate simple C(sp³)-H bonds or utilize readily available chemical feedstocks. Key mechanistic paradigms, including photoredox/transition metal dual catalysis, metal-catalyzed radical processes, and photo-induced ligand-to-metal charge transfer (LMCT), are critically discussed. This review evaluates the mechanistic insights, applications, and limitations of these methodologies in the synthesis of organophosphorus compounds, and provides perspectives on future directions to promote further advancements in C(sp³)-P bond formation strategies. [Display omitted] [ABSTRACT FROM AUTHOR]

α-Substituted-7-azaindoline amides and α,β-unsaturated 7-azaindoline amides have emerged as new versatile synthons for various metal-catalyzed and organic-catalyzed asymmetric reactions, which have attracted much attention from chemists. In this review, the progress of research on 7-azaindoline amides in the asymmetric aldol reaction, the Mannich reaction, the conjugate addition, the 1,3-dipole cycloaddition, the Michael/aldol cascade reaction, aminomethylation and the Michael addition-initiated ring-closure reaction is discussed. The α-substituted-7-azaindoline amides, as nucleophiles, are classified according to the type of α-substituted group, whereas the α,β-unsaturated 7-azaindoline amides, as electrophiles, are classified according to the type of reaction.

Allenes with two carbon–carbon double bonds belong to a unique class of unsaturated hydrocarbons. The central carbon atom of allene is sp hybridized and forms two σ-bonds and two π-bonds with two terminal sp2 hybridized carbon atoms. The chemistry of allenes has been well documented over the last decades. They are more reactive than alkenes due to higher strain and exhibit significant axial chirality, thus playing a vital role in asymmetric synthesis. Over a variety of organic transformations, allenes specifically undergo classical metal catalyzed cycloaddition reactions to obtain chemo-, regio- and stereoselective cycloadducts. This review briefly describes different types of annulations including [2+2], [2+2+1], [3+2], [2+2+2], [4+2], [5+2], [6+2] cycloadditions using titanium, cobalt, rhodium, nickel, palladium, platinum, gold and phosphine catalyzed reactions along with a mechanistic study of some highlighted protocols. The synthetic applications of these reactions towards the synthesis of natural products such as aristeromycin, ent-[3]-ladderanol, waihoensene(−)-vindoline and (+)-4-epi-vindoline have also been described. [ABSTRACT FROM AUTHOR]

Thioester constitutes a fundamentally unique intermediate, engaged in various biosynthesis processes in living systems as well as a versatile synthon in modern organic synthesis. Transition metal catalysis and radical reaction manifolds have enabled to enrich the repertoire of synthetic methods for thioesters. In this review, we have accommodated the recent reports on modern strategies towards thioester synthesis from a plethora of readily available feedstocks, such as alkenes, alkynes, alcohols, phenols or commodity chemicals/synthetic building blocks like organic aldehydes, halides or organoboron reagents under various catalysis domains. Furthermore, the momentous advancements of employing progenitors of odorous thiols as well as CO‐surrogates have contextually been emphasized, alongside the utilization of native free thiols and CO gas. [ABSTRACT FROM AUTHOR]

In recent years, organoboron compounds has attracted much attention due to their unique chemical properties. In this Review, we summarize catalytic reactions via the dual catalysis of boron and another catalyst, which showed specific catalytic activity in organic transformations. [ABSTRACT FROM AUTHOR]

This critical review discusses the synthesis of alcohols via hydrogenation of carboxylic acids promoted by heterogeneous metal catalysis. The introductory chapter rationalizes the comparative reactivity of carboxylic acid derivatives, which is proceeded by a description of different mechanisms for carboxylic acid hydrogenation. Reaction pathways are discussed that give rise to undesired side products, before comparing the reactivity of different classes of carboxylic acid substrates with a focus on biomass‐derived carboxylic acids. The final portion of the review aims to guide researchers in the selection of appropriate reaction conditions, such as the choice of solvent, transition metal, and catalyst support. [ABSTRACT FROM AUTHOR]

This account highlights work from my laboratory at the University of Wollongong (UOW), concerning nitrogen heterocycles and alkaloids, from my appointment as lecturer in Chemistry in February 1985 to the present time as an Emeritus Professor since 2022. I am thankful to the Royal Australian Chemical Institute for the recognition of my work through the recent award of a Distinguished Fellow at the national conference in Brisbane in July 2022. This Account highlights the work of Stephen G. Pyne on nitrogen heterocycles and alkaloids over 37 years at the University of Wollongong, NSW, Australia. [ABSTRACT FROM AUTHOR]

The necessity of more sustainable conditions that follow the twelve principles of Green Chemistry have pushed researchers to the development of novel reagents, catalysts and solvents for greener asymmetric methodologies. Solvents are in general a fundamental part for developing organic processes, as well as for the separation and purification of the reaction products. By this reason, in the last years, the application of the so-called green solvents has emerged as a useful alternative to the classical organic solvents. These solvents must present some properties, such as a low vapor pressure and toxicity, high boiling point and biodegradability, and must be obtained from renewable sources. In the present revision, the recent application of these biobased solvents in the synthesis of optically active compounds employing different catalytic methodologies, including biocatalysis, organocatalysis and metal catalysis, will be analyzed to provide a novel tool for carrying out more ecofriendly organic processes. [ABSTRACT FROM AUTHOR]

Convergent paired electrolysis combines both anodic and cathodic reactions simultaneously in an electrochemical transformation. It provides a highly energy‐efficient and divergent approach to conventionally challenging and useful structures. However, the physical separation of the two half‐electrode reactions makes it extremely difficult to couple the intermediates arising from the two electrodes. In this concept article, four strategies used in convergent paired electrolysis will be discussed from the perspective of the reaction mechanism: a) metal‐catalyzed convergent paired electrolysis, b) convergent paired electrolysis enabled by persistent radical effects, c) microfluidic chemistry applied to convergent paired electrolysis, and d) alternating current electrolysis. [ABSTRACT FROM AUTHOR]

The synthesis of organoboron compounds have attracted the attention of the synthetic community. In particular, molecules with C(sp2)‐B bonds enable the transformation to new C−C or C‐heteroatom bonds by well‐established methodologies. Alkenyl boronates have the possibility for further conversion of the boron moiety or functionalization of the double bond. This review gives an overview on the recent methodologies for the selective preparation of the challenging highly substituted alkenyl boronates from alkynes. [ABSTRACT FROM AUTHOR]

Ipatasertib is a potent small molecule Akt kinase inhibitor currently being tested in Phase III clinical trials for the treatment of metastatic castration-resistant prostate cancer and triple negative metastatic breast cancer. In this paper an overview of the development achievements towards the commercial manufacturing process is given. The convergent synthesis consists of ten steps with eight isolated intermediates and utilizes a wide range of chemical techniques and technologies to build-up this complex drug. All three stereocenters are introduced using enzyme or metal catalysis.

Optically pure 3,4-dihydroquinoxalin-2-ones, being members of the privileged quinoxaline family, received significant interest in organic synthesis, more particularly in medicinal chemistry, proving also to be useful building blocks for facile entry to a relevant bioactive pharmacophore, namely tetrahydroquinoxalines. The first asymmetric approaches to 3,4-dihydroquinoxalin-2-ones relied on classical use of chiral pool available reagents and auxiliares, such as α-amino acids and mandelates/tartaric acid derivatives, respectively. Over the years, more general and appealing enantioselective catalytic routes have been developed, mainly concerned with metal- and organocatalyzed reduction of quinoxalinones. Additionally, different organocatalytic cyclization strategies, including sustainable one-pot processes, have been added to the synthetic toolbox. This perspective aims to showcase the state of art of asymmetric approaches developed to prepare 3,4-dihydroquinoxalin-2-ones with a focus on catalytic routes, highlighting challenges and opportunities for future developments.

Hydrothermal systems are areas in which heated fluids and organic molecules rush through basaltic material rich in metals and minerals. By studying malononitrile and acetonitrile, we examine the effects of metal and mineral nanoparticles on nitrile compounds in anoxic, hydrothermal conditions representing a prebiotic environment of early Earth. Polymerization, reduction, cyclization, and a phenomenon colloquially known as ‘chemical gardening’ (structure building via reprecipitation of metal compounds or complexing with organics) are all potential outcomes with the addition of metals and minerals. Reduction occurs with the addition of rhodium (Rh) or iron (II) sulfide (FeS), with positive identification of ethanol and ethylamine forming from acetonitrile reduction. We find that polymerization and insoluble product formation were associated with oxide minerals, metallic nickel (Ni), and metallic cobalt (Co) acting as catalysts. Oxide minerals strongly promoted polymerization into insoluble, tar-like products of nitriles. FeS, iron-nickel alloy (FeNi), and rhodium are unique cases that appear to act as reagents by actively participating in chemical gardening without returning to their initial state. Further, FeS tentatively had a phase change into the mineral parabutlerite. This research aims to identify metals and metal minerals that could best serve nitrile catalysis and reactions on early Earth.

Sequential reactions of aminoalkynes represent a powerful tool to easily assembly biologically important polyfunctionalized nitrogen heterocyclic scaffolds. Metal catalysis often plays a key role in terms of selectivity, efficiency, atom economy, and green chemistry of these sequential approaches. This review examines the existing literature on the applications of reactions of aminoalkynes with carbonyls, which are emerging for their synthetic potential. Aspects concerning the features of the starting reagents, the catalytic systems, alternative reaction conditions, pathways and possible intermediates are provided.

Background: The combination of metal-catalyzed reactions and enzyme catalysis has been an essential tool for synthesizing chiral pharmaceutical intermediates in the field of drug synthesis. Metal catalysis commonly enables the highly efficient synthesis of molecular scaffolds under harsh organic conditions, whereas enzymes usually catalyze reactions in mild aqueous medium to obtain high selectivity. Since the incompatibility between metal and enzyme catalysis, there are limitations on the compatibility of reaction conditions that must be overcome. Findings: We report a chemoenzymatic cascade reaction involved Palladium (Pd) catalyzed Suzuki–Miyaura coupling and whole-cell catalyzed C = O asymmetric reduction for enantioselective synthesis of value-added chiral alcohol. The cell membrane serves as a natural barrier can protect intracellular enzymes from organic solvents. Conclusions: With dual advantages of cascade catalysis and biocompatibility, our work provides a rational strategy to harvest chiral alcohols in high yield and excellent enantioselectivity, as a channel to establish chemoenzymatic catalysis. [ABSTRACT FROM AUTHOR]

The catalytic enantioselective alkynylation of isatins, catalyzed by a Zn(OCOCF3)2/chiral bis(sulfonamide)‐diamine (BSDA) catalyst under mild condition, has been developed. The desired chiral 3‐alkynyl‐3‐hydroxy‐2‐oxindoles were obtained in moderate to excellent yields (up to 96%) and good to excellent enantioselectivites (up to 97% ee). The reaction is broad in scope with respect to aryl‐substituted terminal alkynes and substituted isatins. [ABSTRACT FROM AUTHOR]

The kinetic resolution (KR) of racemates is one of the most widely used approaches to access enantiomerically pure compounds. Over the past two decades, catalytic nonenzymatic KR has gained popularity in the field of asymmetric synthesis due to the rapid development of chiral catalysts and ligands in asymmetric catalysis. Chiral tertiary alcohols are prevalent in a variety of natural products, pharmaceuticals, and biologically active chiral compounds. The catalytic nonenzymatic KR of racemic tertiary alcohols is a straightforward strategy to access enantioenriched tertiary alcohols. This short review describes recent advances in catalytic nonenzymatic KR of tertiary alcohols, including organocatalysis and metal catalysis. 1 Introduction 2 Organocatalysis 2.1 Peptide Catalyst 2.2 Chiral Phosphoric Acid Catalyst 2.3 Chiral Lewis Base Catalyst 2.4 Chiral Quaternary Ammonium Salt Catalyst 3 Metal Catalysis 3.1 Mixed La-Li Heterobimetallic Catalyst 3.2 Rh Catalyst 3.3 Hf Catalyst 3.4 Pd Catalyst 3.5 Cu Catalyst 3.6 Ag Catalyst 4 Conclusion and Outlook [ABSTRACT FROM AUTHOR]

C−H activation and functionalization is quite promising in recent days as the strategy offers a go‐to general method for different bond formations and hence grants synthetic versatility. At the same time, imidazopyridine, a fused bicycle of imidazole moiety with pyridine ring, has a profound impact due to its ubiquitous and prodigious application in medicinal as well as material chemistry. The presence of N‐1 atom in 2‐arylImidazo[1,2‐a]pyridine facilitates the coordination with metal catalysts leading to the formation of ortho‐substituted products. This review summarizes all the articles on ortho C−H functionalization of 2‐arylImidazo[1,2‐a]pyridines published till August 2021. [ABSTRACT FROM AUTHOR]

The use of (benzo)pyrylium salts as versatile synthetic building blocks has become an attractive platform for the preparation of valuable heterocyclic compounds. Besides other numerous direct applications of (benzo)pyryliums, the intrinsic electrophilic nature of these species or the dipole character of the related oxidopyrylium derivatives have been exploited towards the development of enantioselective transformations such as nucleophilic dearomatization and cycloaddition reactions. This review aims at providing an overview on the relevant catalytic enantioselective methodologies developed in the past years, which are presented considering the involved metal- and/or organic catalytic system, as well as the type of reaction.

This review briefly describes the evolution of organometallic chemistry and photoredox catalysis as independent fields; followed by a more in-depth presentation and discussion of representative examples derived from their synergistic combination, which generally leads to powerful cross-coupling protocols. In this context, the rational deconvolution of these complex catalytic systems into their isolated, more simple components are evaluated in order to understand their properties and reactivities.