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This Short Review summarizes the synthesis and applications of triarylboranes (BAr3), including both homoleptic and heteroleptic species, with a focus on the modification of their electronic and structural properties via the introduction of meta -substituents with respect to the B atoms to their Ar groups. This approach constitutes a complementary alternative to conventional strategies for the design of BAr3 , which are usually based on a modification of their ortho - and/or para -substituents. An initial analysis revealed that CH3 and F are the most common meta -substituents in hitherto reported BAr3 (apart from the H atom). Thus, an extensive exploration of other substituents, e.g., heavier halogens, longer or functionalized alkyl groups, and aryl groups, will increase our knowledge of the structure and reactivity of BAr3 and eventually lead to a range of new applications. 1 Introduction 2 Scope of this Review 2.1 The Electronic and Steric Influence of meta -Substituents 2.2 Molecular Transformations Mediated by meta -Substituted Boranes 2.3 Other Examples of meta -Functionalization of BAr3 3 Conclusions and Perspectives [ABSTRACT FROM AUTHOR]

Vicinal stereogenic centers represent prevalent structural motifs in organic synthetic chemistry, and their construction poses a longstanding challenge. Transition-metal-catalyzed asymmetric allylic substitution has become a well-established enantioselective C–C bond-forming reaction. When these reactions involve a prochiral nucleophile and an allylic electrophile with a terminal substituent, the creation of vicinal stereogenic centers becomes feasible. However, despite remarkable achievements having been accomplished, realizing this transformation with precise control over both the enantio- and diastereoselectivity remains a significant challenge. To address the stereoselective challenges, the introduction of a second catalyst to the transition-metal-catalyzed asymmetric allylic alkylation to control the diastereoselectivity during C–C bond formation has proven particularly fruitful. In this short review, we aim to highlight recent advances in dual catalysis that enable diastereo- and enantioselective allylic substitutions. 1 Introduction 2 Construction of Vicinal Stereogenic Centers by Organo and Metal Dual Catalysis 2.1 Chiral Phase-Transfer Catalysis and Transition-Metal Dual Catalysis 2.2 Chiral Amine and Transition-Metal Dual Catalysis 2.3 NHC and Transition-Metal Dual Catalysis 2.4 Chiral Aldehyde and Transition-Metal Dual Catalysis 2.5 Chiral Lewis Base and Transition-Metal Dual Catalysis 3 Construction of Vicinal Stereogenic Centers by Metal and Metal Dual Catalysis 3.1 Lewis Acidic Metal and Iridium Dual Catalysis 3.2 Lewis Acidic Metal and Palladium Dual Catalysis 3.3 Palladium and Ruthenium Dual Catalysis 3.4 Other Advancements in the Construction of Vicinal Stereogenic Centers through Synergistic Bimetallic Catalysis Enabling Asymmetric Allylic Alkylation 4 Conclusions and Future Outlook [ABSTRACT FROM AUTHOR]

A relay catalytic system is developed for the asymmetric hydrogenative coupling of indoles with α,β-unsaturated ketones, affording enantioenriched chiral γ-indole alcohols with broad substrate scope and excellent enantioselectivities (32 examples, up to >99% ee). Mechanistic studies suggest that the relay catalytic system consists of copper-catalyzed alkylation and ruthenium-catalyzed asymmetric hydrogenation. [ABSTRACT FROM AUTHOR]

Nickel catalysis is a well-established and powerful tool for C–C cross-coupling reactions, and its versatility has expanded significantly over past decades by its combination with visible-light photocatalysis in metallaphotoredox chemistry. Photocatalysis enables the activation of traditionally inert substrates and turnover of the Ni catalyst through a single-electron transfer processes. In recent years, dual catalysis has been further empowered by photoactive Ni intermediates, which exhibit distinct reactivity profiles from their ground states and complement existing protocols. This short review focuses on the emergent subclass of metallaphotoredox catalysis in which the synergy of a photoactive Ni catalyst and a typical photocatalyst (e.g., a polypyridyl Ir complex) provide solutions to challenging C–C bond formation. 1 Introduction 2 Photoactive Nickel Complexes 3 HAT-Mediated C–C Cross-Coupling 4 Halofunctionalization of π-Systems 5 Photoelimination of an Aryl Radical 6 Conclusion [ABSTRACT FROM AUTHOR]

We describe the use of acyl imidazoles derived from aliphatic carboxylic acids for the N-heterocyclic carbene/organic photoredox co-catalyzed meta -selective functionalization of electron-rich arenes. Compared to our previous work, a change of the wavelength of the applied LED light from 440 nm to 390 nm promotes this reaction efficiently. [ABSTRACT FROM AUTHOR]

A diversity-oriented total synthesis for Amaryllidaceae alkaloids incorporating the frequently found C3a-arylated hydroindole moiety was developed. Chiral-anion-induced gold(I) catalysis was employed for the cyclization of 1,4-diynes to the pyrrolidine and the installation of the all-carbon quaternary stereocenter. Both enantiomeric series of crinine-type alkaloids in high enantiopurity were accessible by this methodology. The formal synthesis of a wide range of Amaryllidaceae alkaloids is described, such as (+)-vitattine, (–)- epi -vitattine, (–)-elwesein, (–)- epi -elwesein, (–)-crinine, (–)- epi -crinine, (–)-buphanisine, (–)-flexinine, and (+)-gracilamine. [ABSTRACT FROM AUTHOR]

The organocatalytic asymmetric benzylation of Morita–Baylis–Hillman (MBH) carbonates with 2,4-dinitrotoluene derivatives as nucleophiles is described. The developed reaction provides a straightforward access to functionalized 2,4-dinitrotoluene derivatives of biological and synthetic relevance. Highly functionalized products have been chemoselectively and efficiently obtained in good to high yields (up to 84%) and with excellent stereoselectivity (up to >20:1 dr, >99 ee). [ABSTRACT FROM AUTHOR]

In the past few decades, transition-metal-catalyzed direct amination of aryl halides with ammonia has attracted significant attention from chemists because of its broad substrate scope, good functional group compatibility, and high reaction selectivity. Herein, recent examples of transition-metal-catalyzed syntheses of aniline derivatives starting from aryl halides are reviewed. 1 Introduction 2 Heat-Driven Transition-Metal-Catalyzed Amination of Aryl Electrophiles 2.1 Palladium-Catalyzed Amination 2.2 Copper-Catalyzed Amination 2.3 Nickel-Catalyzed Amination 3 Light-Driven Transition-Metal-Catalyzed Amination of Aryl Electrophiles 4 Conclusion and Outlook [ABSTRACT FROM AUTHOR]

A general Pd-catalyzed approach for the conversion of phenols into benzonitriles via aryl imidazolylsulfonates with a non-toxic cyanide source, potassium ferrocyanide, has been developed. Salient features of this method include low palladium precatalyst loadings (as low as 1.0 mol% total Pd), mild reaction conditions, and environmentally benign by-products compared to other (pseudo)halide aryl electrophiles. The initial scope of the reaction on a range of phenolic precursors is demonstrated including a one-pot, two-step approach to convert phenols directly into benzonitriles. [ABSTRACT FROM AUTHOR]

Reported here is the iridium-catalyzed regio- and enantio-selective secondary benzylic C–H borylation using benzothiazole as the directing group. Various monosubstituted 2-arylalkylbenzo[ d ]thiazole were well-tolerated, affording the corresponding products in moderate to good yields with good enantioselectivity. The C–B bond in one boryl-ated product could undergo stereospecific transformations to form a series of C–C and C–heteroatom bonds. [ABSTRACT FROM AUTHOR]

A simple, direct, and regioselective protocol to substituted 5-iodo-4 H -quinoxalines through double C–N arylations of 1,2,3-triiodobenzenes and 1,2-diamines is reported. Remarkably, the N-arylation couplings proceed unimolecularly at the vicinal positions, the most active and less hindered positions. This process tolerates a wide range of aromatic substrates. The reactions of electron-deficient 1,2,3-triiodoarene systems and DMEDA under the optimized conditions provided the highest isolated yields. The chemical transformation of the target compound, which serves as a valuable precursor in synthesis, was successfully demonstrated in the Suzuki–Miyaura reaction, giving the desired coupling derivatives with excellent isolated yields. This article describes a method for the first and unprecedented synthesis of 5-iodo-4 H -quinoxalines that is regioselective, scalable, and provides useful derivatives for other chemical reactions [ABSTRACT FROM AUTHOR]

Five- and six-membered cyclic amide structures with an embedded endocyclic α-aza group (α-aza-lactams) not only represent masked or protected forms of α-amino acids, but also form the core of other medicinally relevant compound families such as (thio)hydantoins and di(tri)ketopiperazines. In recent years, catalytic methods have been discovered to synthesize these molecular scaffolds, particularly those bearing an α-stereogenic tri- or tetrasubstituted carbon center, enantioselectively. The wide variety of methods and catalytic activation strategies that have been successfully applied to this end in a short period of years is notable. This short review covers the most significant, highlighting their differences and complementarities. The methods are organized according to the disconnection approach to the target α-aza-lactam structure, which in most cases is deeply bound to the type of catalysis applied. 1 Introduction 2 Catalyst-Controlled Cα –H Functionalization (Approach a) 3 Decarboxylative α-AAA Reactions (Approach b) 4 Cα –X Substitution Reactions (Approach c) 5 De Novo Synthesis from Acyclic Precursors (Approach d) 6 Hydrogenation of (Addition to) α-Alkyliden-α-aza-lactams (Approach e) 7 Kinetic Resolution and Deracemization (Approach f) 8 Conclusions [ABSTRACT FROM AUTHOR]

The Vilsmeier–Haack reaction of ketones with DMF and POCl3- produced 3-chloroacrylcarbaldehydes, which were converted into the corresponding (Z)-4-[(Z)- or (Z)-4-[(E)-3-chloroallylidene)-2-phenyloxazol-5(4 H)-ones] (azlactones) or their isomeric mixtures when heated with hippuric acid in propionic anhydride. It was shown that the alcoholysis products of these compounds, resulting from the opening of the oxazolone ring, undergo copper-catalyzed intramolecular cross-coupling reactions with the formation of methyl 1 H -pyrrole-2-carboxylates. Thus, a one-pot method was developed for the synthesis of methyl 1 H -pyrrole-2-carboxylates starting from 4-(3-chloroallylidene)-2-phenyloxazol-5(4 H)-ones. [ABSTRACT FROM AUTHOR]

This short review showcases the developing field of C–H activation reactions, with a particular focus on green catalysis through the use of environmentally friendly solvents. It evaluates the effects of these solvents on reaction outcomes, environmental aspects and general efficacy, highlighting their advantages that lead to greater selectivity, lower levels of toxicity and enhanced reaction rates. Water and biobased alternatives such as polyethylene glycols, glycerol, 2-methyltetrahydrofuran, γ-valerolactone, methanol, ethanol, p -cymene and diethyl carbonate are representative examples of such solvents. The scope of this short review encompasses studies of different methodologies, catalysts, and reaction conditions that help to develop C–H activation reactions utilizing green solvents. 1 Introduction 2 Water 3 Polyethylene Glycols (PEGs) 4 Glycerol 5 2-Methyltetrahydrofuran (2-MeTHF) 6 γ-Valerolactone (GVL) 7 Methanol 8 Ethanol 9 p -Cymene 10 Diethyl Carbonate 11 Conclusion [ABSTRACT FROM AUTHOR]

In this article we have focused on the use of selenium in catalysis along with the proposed reaction mechanisms. With increasing interest in selenium chemistry, we have highlighted the most significant features of this subject, mainly in the last years. Selenium-containing catalysts have a key role in many transformations; for example, oxidation reactions that are performed under very mild and controlled conditions. In addition, utilizing the weak selenium–oxygen bonding interaction has proved to be very useful as a catalytic approach for specific transformations. The catalytic cycles of each appropriate transformation are fully reviewed. 1 Introduction 2 Use of Selenium in Catalysis: Perspectives 2.1 Selenium as Directing Group: Preparation of Organoselenium Compounds via C–H Borylation 2.2 Multicomponent Reactions Employing Selenium as a Catalyst 2.3 Selenium-π-Acid Catalysts 2.4 Electrochemical Selenium-Catalyzed Reactions 2.5 Stereoselective Synthesis Employing Organoselenium Catalysts 2.6 Transition-Metal Catalysts Containing Selenium-Based Ligands 2.6.1 Selenium-Ligated Palladium(II) Complexes as Catalysts for the Heck Reaction 2.6.2 Pincer Selenium Catalyst for the Allylation of Aldehydes and Closely Related Functional Groups 2.6.3 Selenium Employed in Buchwald-Type C–N Coupling Reactions 2.6.4 Organoselenium Catalysts in Suzuki–Miyaura Coupling Reactions 2.7 Organoselenium Catalysis in Michael-Type Reactions 2.8 Catalytic Cycle for Glutathione Peroxidase 2.9 Epoxidation 2.10 Dihydroxylation 2.11 Oxidation 2.12 Bromolactonization 2.13 Preparation of Alkenes from Vicinal Diols 2.14 Preparation of α-Selanyl Enals from Propargylic Alcohols 2.15 Miscellanea 3 Concluding Remarks [ABSTRACT FROM AUTHOR]

This document provides information on the use of photoacid generators (PAGs) in catalysis, specifically in the Friedel-Crafts alkylation of indoles with aldehydes/ketones. The study focuses on diarylethenes and terarylenes as PAGs, which have advantages such as high quantum yields and autonomy. The researchers developed an environmentally friendly method for synthesizing diindolylmethane derivatives with potential antibacterial, antitumor, and antifungal activities. The document also provides detailed information on the synthesis and characterization of various compounds, including their physical properties and spectroscopic data. This information can be useful for researchers studying these compounds and their properties. [Extracted from the article]

This article explores the synthesis of α,β-unsaturated carbonyl compounds, which have applications in pharmacology and materials science. It discusses various methods for synthesizing these compounds, with a focus on the use of earth-abundant metals like iron and cobalt as catalysts. The authors explain the mechanisms involved in these reactions and highlight the advantages of using earth-abundant metals. While these methods have been used in the synthesis of pharmaceuticals and bioactive molecules, there are still challenges to overcome, and more research is needed to develop more efficient and environmentally friendly catalytic systems. [Extracted from the article]

This document explores the use of ligand-to-metal charge transfer (LMCT) catalysis with base metals, such as nickel, cobalt, and copper, in organic transformations. The authors discuss recent advancements in the field and the potential for expanding the synthetic repertoire of this strategy. They emphasize the importance of refining ligands to promote organometallic mechanisms and further developing photoinduced LMCT for sustainable synthetic methods. The document includes contributions from researchers Sean M. Treacy and Tomislav Rovis, who have made significant contributions to the field. [Extracted from the article]

This article discusses a new method for synthesizing homoallylic alcohols, which are commonly found in synthetic intermediates and bioactive molecules. The authors describe a three-component reaction using specific catalysts, which allows for the creation of a diverse range of homoallylic alcohols. The article also includes detailed procedures for the synthesis and purification of these compounds, as well as their characterization using various analytical techniques. The information is presented in a technical manner and is intended for researchers in the field. [Extracted from the article]

This article explores the use of light-controlled catalysis triggered by ligand photodissociation from cobalt complexes. The researchers developed a method that allows for the switching between two different reaction outcomes based on the presence or absence of visible light. They demonstrated this approach in hydroboration reactions and achieved selective catalysis for 1,2- or 1,4-addition depending on the reaction conditions. The researchers also investigated the mechanism behind these reactions and used the method to access enolborates and syn-aldol products. This research has the potential to expand the possibilities for catalytic reactions and could lead to further advancements in the field. [Extracted from the article]

This document provides technical information about the synthesis and characterization of three chemical compounds. The compounds are described in terms of their nuclear magnetic resonance (NMR) spectra, high-resolution mass spectrometry (HRMS) data, and physical properties. The text also acknowledges financial support from the CAS-TWAS fellowship. The information is presented in a scientific manner and may be useful for researchers studying organic chemistry. [Extracted from the article]

This article explores the use of thioether-containing ligands in catalysis applications. Thioether ligands, which contain a sulfur atom, have traditionally been less considered due to their lower donor and acceptor character compared to phosphorus ligands. However, ligands with a low degree of oxidation and a combination of sulfur with another heteroatom have shown promise in generating interesting catalysts. The article provides examples of enantioselective and non-enantioselective reactions using thioether ligands and discusses the advantages of combining sulfur with another heteroatom. The paper is organized based on the type of heteroatom that accompanies the thioether function, such as phosphorus and nitrogen. Various catalytic systems involving thioether ligands for different organic transformations are discussed, including dihydroboration, cyclopropanation, silyl-hydrogen insertion, C-H functionalization, and C-H alkenylation. The ligands play a crucial role in enhancing the activity and selectivity of the catalysts, and they have been successfully applied to a wide range of substrates. Mechanistic studies have provided insights into the reaction pathways and the role of the ligands in facilitating the transformations. The article highlights the potential of thioether-functionalized ligands in metal-catalyzed reactions and suggests a promising future for sulfur in catalysis. [Extracted from the article]

This article discusses the development of sustainable catalytic chemical methods for O-glycosylation using iron-based salts as catalysts. The authors experiment with different reaction conditions and optimize the yield of the glycosylation reaction. The study demonstrates the potential of iron-based salts as a sustainable and affordable alternative for large-scale synthesis. The article provides detailed information about the synthesis and characterization of various compounds, including their yields, physical properties, and spectroscopic data. This information can be useful for researchers studying organic chemistry or interested in the synthesis and characterization of specific compounds. [Extracted from the article]

This article discusses the development of a clinical compound, PF-06842874, for the treatment of Pulmonary Arterial Hypertension (PAH). The authors focus on the synthesis of the compound and the challenges faced in the process, such as low purity and the use of undesirable solvents. They explore different coupling methods and identify a Pd-catalyzed Buchwald-Hartwig coupling as the most effective approach. The article provides valuable insights into the development of a potential treatment for PAH and describes a robust and scalable process for the synthesis of the compound. [Extracted from the article]

This article provides an overview of recent advancements in C–H functionalization using NHC-Ni/Al bimetallic catalysis. The combination of N-heterocyclic carbene (NHC) ligands with nickel and aluminum catalysts allows for the activation of C–H bonds, enabling the direct functionalization of aromatic compounds. The use of bulkier and electron-donating NHC ligands has improved reactivity, and chiral NHC ligands have enabled enantioselective C–H alkylation reactions. However, challenges remain, and further research is needed to expand the range of substrates and reactions and develop new ligands and catalysis modes for wider synthetic applications. [Extracted from the article]

This article explores the use of fluorinated triarylborane catalysts to activate diazo compounds in organic synthesis. Traditional metal-catalyzed methods have limitations, but borane catalysis offers a transition-metal-free and environmentally friendly approach. The article discusses the reactivity of diazo compounds with triarylboranes, including the binding sites and mode of N2 release. Various reactions using diazo compounds as a carbene synthon in the presence of borane catalysts are catalogued, including O–H bond insertion, S–H insertion, N-alkylation, C–H functionalization, and synthesis of carbocycles and azides. The authors highlight the potential of borane catalysis to advance organic synthesis and offer new directions in synthetic methodology. [Extracted from the article]

This article discusses the emerging trends in glycoscience, focusing on the importance of synthetic carbohydrate chemistry. Carbohydrates are abundant biomolecules with various applications in chemistry, biology, and medicine. They play a crucial role in biological processes such as energy storage, protein function modulation, and immune response. The article presents advancements in the synthesis of carbohydrates and their applications in catalysis, medicine, and materials science. It also highlights the contributions of various experts in the field and emphasizes the potential of glycoscience for future research and development. [Extracted from the article]

(E)- N -(2-Cyclohexyl-1-phenyl-3-(trimethylsilyl)allyl)aniline (19) General procedure A was used to react I N i -benzylaniline (183 mg, 1.0 mmol) with (cyclohexylethynyl)trimethylsilane (180 mg, 1.0 mmol) in the presence of catalyst B II-Bu b (111 mg, 0.1 mmol) for 24 h at 140 °C. Keywords: alkynes; allylamines; C-H activation; hydroaminoalkyl-ation; titanium; catalysis EN alkynes allylamines C-H activation hydroaminoalkyl-ation titanium catalysis 3759 3776 18 11/01/23 20231116 NES 231116 Graph The catalytic hydroaminoalkylation of alkenes [1][8] (Scheme 1), which takes place by a 100% atom-economical addition of the -C-H bond of a primary, [8] secondary, [8][8][8][8] or tertiary [8][8] amine across the alkene double bond, has received considerable attention over the past 15 years. N -(3,3-Dimethyl-2-methylenebutyl)aniline (1) 4d General procedure A was used to react I N i -methylaniline (107 mg, 1.0 mmol) with I tert i -butylacetylene (99 mg, 1.2 mmol) in the presence of catalyst B II-DIPP b (194 mg, 0.1 mmol) for 24 h at 140 °C. 3-Chloro- N -(3,3-dimethyl-2-methylenebutyl)aniline (5) General procedure A was used to react 3-chloro- I N i -methylaniline (142 mg, 1.0 mmol) with I tert i -butylacetylene (99 mg, 1.2 mmol) in the presence of catalyst B II-DIPP b (194 mg, 0.1 mmol) for 24 h at 140 °C. N -(3,3-Dimethyl-2-methylenebutyl)-4-(trifluoromethoxy)aniline (7) General procedure A was used to react I N i -methyl-4-(trifluoromethoxy)aniline (191 mg, 1.0 mmol) with I tert i -butylacetylene (99 mg, 1.2 mmol) in the presence of catalyst B II-DIPP b (194 mg, 0.1 mmol) for 24 h at 140 °C. [Extracted from the article]

SP 1 sp H NMR (500 MHz, CDCl SB 3 sb ): = 8.33 (d, I J i = 8.1 Hz, 1 H), 7.81 (d, I J i = 6.5 Hz, 1 H), 7.73 (d, I J i = 6.5 Hz, 1 H), 7.67 (d, I J i = 6.8 Hz, 1 H), 7.57 (s, 3 H), 7.48 (d, I J i = 6.8 Hz, 1 H), 7.36-7.27 (m, 4 H), 7.17 (t, I J i = 7.4 Hz, 4 H), 7.08 (s, 1 H), 6.92 (s, 1 H). Keywords: arylation; catalysis; P-ligand directed C-H activation; rhodium; trifluoromethylsulfonates; oxazoles EN arylation catalysis P-ligand directed C-H activation rhodium trifluoromethylsulfonates oxazoles 3589 3599 11 10/19/23 20231102 NES 231102 Graph Selective transition-metal-catalyzed C-H activation/functionalization reactions conducted with pseudo(halide) coupling partners obtained from renewable resources, such as alcohols and phenols, [1] complement advantageously the classical use of organic halides that are typically generated from fossil resources. Benchmark SP 1 sp I J i SB PSe sb value for Ph SB 3 sb P(Se) = 730 Hz; SP 31 sp P NMR (162 MHz, CDCl SB 3 sb ) for [(Ph SB 3 sb P)AuCl] = 57.1 ppm. Aryl Triflates in Phosphorus-Directed Rhodium(III)-Catalyzed C-H Activation. [Extracted from the article]

Keywords: cross-coupling; copper; catalysis; heterocycles; alkynes EN cross-coupling copper catalysis heterocycles alkynes 2370 2376 7 07/14/23 20230801 NES 230801 Graph The FDA has approved 37 new drugs and combination therapies in 2022. [13][14][15] Metalloamination/cyclization promoted by diethylzinc proceeded optimally at 90 °C when benzotrifluoride (BTF) was used as the reaction solvent, although toluene and even 1,2-DME can be substituted. The J. Young tube was placed in a 90 °C oil bath and the cyclization reaction was monitored by NMR (indicated by the recession of the alkene peaks), using BTF as an internal standard. [Extracted from the article]

[1] Our focus will be recent reports of -carbon elimination reactions of cyclopropylcarbinyl intermediates from VCP or ACP starting materials using palladium and rhodium catalysis 5.1 Palladium-Catalyzed -Carbon Eliminations Driven by Release of Ring Strain A commonly used strategy to access cyclopropylcarbinyl palladium species involves the addition of an Ar-Pd(II)-X species to a VCP. [17] Larock [17] and Zhu [17][17] had reported that neopentyl-Pd(II) species can undergo 1,4-palladium migration reactions, which can generate polycyclic scaffolds similar to B int-A b (Scheme 9). The palladium catalyst reacts with the cyclobutanol to effect a C-C bond cleavage that is driven by the release of ring strain to afford an alkyl-Pd(II) species that undergoes reductive elimination to afford the I ipso i -alkylated products. Keywords: catalysis; -carbon elimination; palladium; rhodium; reversible EN catalysis -carbon elimination palladium rhodium reversible 2285 2303 19 07/14/23 20230801 NES 230801 Graph 1 Introduction Transition-metal-catalyzed methodologies have typically sought to forge C-C bonds in order to build molecular complexity. [Extracted from the article]

Anilines selectively arylated at their ortho , meta or para positions are useful building blocks in synthesis and have found applications in many areas. The most straightforward method for their synthesis relies on the direct arylation of a C(sp2)–H bond of anilines, an attractive strategy avoiding the prefunctionalization of the starting anilines provided that such arylations proceed with high levels of regioselectivity. Such reactions are presented and discussed, in a comprehensive manner, in this review article, with an emphasis on the regioselectivity of the processes and factors governing both the reactivity and selectivity. 1 Introduction 2 ortho -Arylation of Anilines 2.1 Direct C(sp2)–H ortho -Arylation of Anilines 2.2 Directed C(sp2)–H ortho -Arylation of Anilines 3 meta -Arylation of Anilines 4 para -Arylation of Anilines 4.1 Direct C(sp2)–H para -Arylation of Anilines via Oxidative Radical Homodimerization 4.2 Direct C(sp2)–H para -Arylation of Anilines via Transition-Metal Catalysis 5 Conclusion and Outlook [ABSTRACT FROM AUTHOR]

In this work, we developed a one-pot, copper-catalyzed aminodifluoroalkylation of enylaniline derivatives. This approach allows the catalytic construction of a broad range of pyrrolidines and piperidines substituted with a gem -difluoro moiety. [ABSTRACT FROM AUTHOR]

A novel approach for the stereoselective construction of N–N atropisomeric compounds by a Pd-catalyzed 5- endo -hydroaminocyclization is described herein. A broad range of bisheterocycles , connected by a configurationally stable N–N stereogenic axis, were prepared with catalyst control in enantioenriched form. [ABSTRACT FROM AUTHOR]

The direct hydrogermylation of alkenes under Lewis acid catalysis is reported. The use of borane B(C6 F5)3 as a catalyst allows for a mild, metal-free hydrogermylation of alkenes and concomitant reduction of ketones and aldehydes. Regardless of electronic biases, anti-Markovnikov hydrogermylation is observed in high yields. Moreover, the process is scalable and proceeds under mild conditions at room temperature. [ABSTRACT FROM AUTHOR]

Trisphosphines, in which two phenylene or vinylene backbones connect three phosphine atoms, belong to an emerging class of ligands in metal-catalyzed organic synthesis and materials applications. However, these ligands were previously known only in a small variety because of the synthetic limitations. We report herein two versatile synthetic routes to a hitherto unavailable variety of trisphosphines. The compounds bearing phenylene backbones were synthesized by sequential addition of two different organolithium reagents to triphenyl phosphite and that with vinylene backbones by stereoretentive addition of lithium diarylphosphide to a cis -bromoalkene. The new trisphosphine compounds will serve as valuable tools for the development of transition-metal-catalyzed reactions and functional materials. [ABSTRACT FROM AUTHOR]

Enantioconvergent transition-metal-catalyzed cross-coupling reactions of racemic α-silyl and α-boryl reagents represent one of the key tools to afford highly enantioenriched α-chiral silanes and boranes. The approach traces back the use of α-silyl nucleophiles, employing palladium precatalysts. More recent work makes use of α-silyl and α-boryl electrophiles under nickel and copper catalysis. The limits of this field have been significantly extended by the design and development of numerous chiral ligands. In this short review, the progress made in this rapidly evolving field is summarized. 1 Introduction 2 α-Silyl Nucleophiles and Electrophiles 2.1 Palladium Catalysis 2.2 Nickel Catalysis 2.3 Copper Catalysis 3 α-Boryl Electrophiles 3.1 Nickel Catalysis 4 Summary and Outlook [ABSTRACT FROM AUTHOR]

Low-valent lanthanide catalysts and reagents are well-established as versatile and tunable mediators for a variety of synthetic transformations. Despite the contemporary interest in electricity as a sustainable alternative to stoichiometric redox reagents, electrochemical (re)generation of such low-valent metal complexes in a synthetic setting is surprisingly limited. With focus on samarium and ytterbium, this review presents a comprehensive overview of electroreductive-mediated transformations with the hope of inspiring further work in this very useful field of research. 1 Introduction 2 Compounds Containing Carbon–Oxygen Bonds 2.1 Ethers 2.2 Aldehydes and Ketones 2.3 Esters and Phthalimides 3 Compounds Containing Nitrogen–Oxygen Bonds 4 Compounds Containing Carbon–Halide Bonds 5 Conclusions [ABSTRACT FROM AUTHOR]

A novel C–H functionalization method was successfully explored by a reductive three molecule coupling of benzaldehydes and esters mediated by samarium and cuprous iodide; thus, the diarylmethanol skeletons were afforded readily via an in situ esterification in one-pot. Substrates including a variety of esters and different benzaldehydes were investigated, and the desired products were readily obtained in moderate to good yields under mild conditions. [ABSTRACT FROM AUTHOR]

Transition-metal-catalyzed asymmetric hydrogenation (AH) is a growing field and a fundamental tool for the construction of chiral compounds. The use of earth-abundant transition metals in AH reactions remains generally limited but has received increased attention in recent years due to cost, sustainability, and environmental concerns. Here, we will summarize progress in first row transition metal catalyzed AH of minimally functionalized alkenes, including scope, mechanism, and challenges in this field. 1 Introduction 2 Ti-Catalyzed AH of Minimally Functionalized Alkenes 3 Zr-Catalyzed AH of Minimally Functionalized Alkenes 4 Co-Catalyzed AH of Minimally Functionalized Alkenes 5 Fe-Catalyzed AH of Minimally Functionalized Alkenes 6 Summary and Outlook [ABSTRACT FROM AUTHOR]

A modified method for iron-catalyzed C–C bond cleavage and amination and alkylation of nonactivated cyclic alcohols has been developed. Using FeCl3 as catalyst, the photoinduced ligand-to-metal charge transfer facilitates the generation of O -radicals from alcohols, the subsequent β-scission, and finally the radical trapping. Compared with the Fe(OR)3 catalysis, this mildly base-free system could enable the amination in a broader substrate scope with higher yields. Moreover, the C–C bond cleavage and alkylation of cyclic alcohols proceeds with electron-deficient olefins under these conditions. [ABSTRACT FROM AUTHOR]

This review highlights transborylation (controlled boron-boron exchange) and its applications as a turnover strategy in boron-catalysed methodologies. Catalytic applications of B –C, B –O, B –N, B –F, B –S, and B –Se transborylations are discussed in the context of transborylation-enabled catalysis, across a wide range of organic transformations including hydroboration, C–C bond formation, C–H borylation, chemoselective reduction, and asymmetric reduction. 1 Introduction 2 B –C Transborylation 3 B –O Transborylation 4 B –N Transborylation 5 B –F Transborylation 6 B –S Transborylation 7 Conclusion [ABSTRACT FROM AUTHOR]

C–H bond oxidation is a powerful means for oxygen incorporation in organic molecules. Its use results in fast structural diversification and in a new way of thinking about retrosynthetic disconnections. In this review, we present the application of five metal-catalyzed methodologies for C(sp 3)–H oxidation in the total synthesis of natural and unnatural products, covering the period of 2004–2022. 1 Introduction 2 Copper-Mediated Hydroxylation of Methylenes β to Imines 3 Palladium Acetoxylation of Methyl Groups β to Oximes 4 Palladium-Mediated Allylic C–H Bond Oxidation of Terminal Olefins 5 Iron- and Manganese-Mediated Aliphatic Oxidation 6 Miscellaneous 7 Conclusion [ABSTRACT FROM AUTHOR]

Chiral sulfoxide is considered to be an ideal candidate ligand for transition-metal-catalyzed asymmetric reactions due to its ease of synthesis, stability, and exceptional S -stereological orientation control. This paper reviews the different types of asymmetrical reactions with chiral sulfoxide ligands in recent years, as well as a discussion of efficient methods for the preparation of some enantiomerically pure sulfoxides. 1 Introduction 2 Chiral Sulfoxides as Ligands in Metal-Catalyzed Asymmetric Catalysis 3 Synthesis of Chiral Sulfoxides 4 Conclusions [ABSTRACT FROM AUTHOR]

A method for radical cyclization of N -methacryloyl-2-arylbenzoimidazoles with nitriles, ketones, and tert -butyl nitrite (TBN) for the preparation of benzimidazo[2,1- a ]isoquinolin-6(5 H)-ones with the advantage of mild reaction conditions, excellent functional group compatibility, and broad substrate scope is reported. The present strategy has favorable characteristics: (1) the use of cheap metal catalysis; (2) N -radical-initiated cyclization of N -methacryloyl-2-arylbenzoimidazoles; and (3) rare example of radical C(sp3)–H functionalization in this cyclization. [ABSTRACT FROM AUTHOR]

A gold-catalysed coupling of aryldiazonium salts with arylboronic acids is described. The reactions proceed in satisfactory yields under irradiation with blue LEDs in the presence of KF and a catalytic amount of ascorbic acid. Notably, 4-nitrobenzendiazonium tetrafluoro-borate is sufficiently reactive to undergo the coupling with a variety of arylboronic acids in the absence of aryl radical initiators. The coupling is applicable for electron-donating and electron-withdrawing groups present at the para , ortho , and meta positions of both substrates. [ABSTRACT FROM AUTHOR]