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Comprehensive Summary: We herein describe a Cp*RhIII‐catalyzed C(sp3)–H mono‐arylation of 8‐methylquinolines with benign arylsilanes. The use of 1‐adamantane carboxylic acid can benefit the efficiency in this transformation, and AgF was both activator and reoxidant. Control experiments indicated inability of C—H cleavage in determining the rate of the reaction. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Concise assembly of spirooxindoles is of great significance but a challenging task in modern organic synthesis. Described herein is an unusual base‐promoted [4+2] spiroannulation of rarely used isatin‐derived β‐silylcarbinols with o‐halogen aromatic ketones, which enables rapid and modular synthesis of six‐membered carbocyclic spirooxindoles in high yields with excellent functional group tolerance (> 50 examples). Mechanistic experiments revealed that this reaction involved a Peterson olefination, Michael addition and intramolecular C(sp3) arylation cascade. The variegated synthetic derivatization of target products and successful construction of bioactive molecules further illustrate the synthetic potential in spirooxindole‐related drug discovery. [ABSTRACT FROM AUTHOR]

The catalytic asymmetric dearomative arylation of 2‐naphthols enabled by the unconventional reactivity of o‐quinone diimides, i. e. the 1,4‐conjugate addition on quinone sp2 hybridized carbon, has been established. Under the catalysis of chiral phosphoric acid, various cyclohexaenones bearing an all‐carbon quaternary stereocenter have been prepared with excellent yields and enantioselectivities. [ABSTRACT FROM AUTHOR]

Isomerisation reactions provide streamlined routes to organic compounds which are otherwise hard to directly synthesise. The most common forms are positional, geometrical or stereochemical isomerisations which involve the relocation of a double bond or a change in relative location of groups in space. In contrast, far fewer examples of structural (or constitutional) isomerisation exist where the connectivity between atoms is altered. The development of platforms capable of such rearrangement poses a unique set of challenges because chemical bonds must be selectively cleaved, and new ones formed without overall addition or removal of atoms. Here, we show that a dual catalytic system can enable the structural isomerisation of readily available allylic alcohols into more challenging‐to‐synthesise α‐arylated ketones via a H‐atom transfer initiated semi‐pinacol rearrangement. Key to our strategy is the combination of a cobalt catalyst and photocatalyst under reductive, protic conditions which allows intermediates to propagate catalytic turnover. By providing an unusual disconnection to structural motifs which are difficult to access through direct arylation, we anticipate inspiring other advanced catalytic isomerisation strategies that will further retrosynthetic logic for complex molecule synthesis. [ABSTRACT FROM AUTHOR]

We developed a redox-neutral synthesis of isoindoloindolone via intramolecular arylation of 2-(1 H -indole-1-carbonyl)benzoic acids. This protocol facilitates the formation of various substituted isoindoloindolones in yields ranging from 17% to 80%. Our mechanistic investigations indicate the pivotal role of NaI: the iodide anion promotes the formation of the desired isoindoloindolone, and the sodium cation suppresses the formation of acylated byproducts, thereby enabling the selective formation of isoindoloindolones in acceptable yields. [ABSTRACT FROM AUTHOR]

Radical‐involved arylative cross‐coupling reactions have recently emerged as an attractive strategy to access valuable aryl‐substituted motifs. However, there still exist several challenges such as limited scope of radical precursors/acceptors, and lack of general asymmetric catalytic systems, especially regarding the multicomponent variants. Herein, we reported a general copper‐Box system for asymmetric three‐component arylative radical cross‐coupling of vinylarenes and 1,3‐enynes, with oxime carbonates and aryl boronic acids. The reactions proceed under practical conditions in the absence or presence of visible‐light irradiation, affording chiral 1,1‐diarylalkanes, benzylic alkynes and allenes with good enantioselectivities. Mechanistic studies imply that the copper/Box complexes play a dual role in both radical generation and ensuing asymmetric cross‐coupling. In the cases of 1,3‐enynes, visible‐light irradiation could improve the activity of copper/Box complex toward the initial radical generation, enabling better efficiency match between radical formation and cross‐coupling. [ABSTRACT FROM AUTHOR]

We report a dual transition metal electrocatalytic approach for C(sp3)–C(sp3) bond cleavage and arylation of cyclic alcohols, providing an efficient and sustainable method for site-specific arylation of ketones. The reaction involves electrophotochemical cerium-catalysed generation of alkoxyl radicals from readily accessible alcohols. Subsequently, homolytic cleavage of the β-C–C bond leads to the generation of carbon-centered radicals that could be effectively utilized by nickel catalysis powered by cathode reduction to deliver the remote arylated ketone products. [ABSTRACT FROM AUTHOR]

An enantioselective arylation of isoxazoles with N‐Cbz‐protected azonaphthalenes is disclosed, affording a range of axially chiral arylisoxazoles in good yields and excellent enantiocontrol by utilizing chiral phosphoric acid. Cbz protecting group can be readily removed, resulting in five‐six membered axially chiral heterobiaryl amines bearing free amine maintaining enantiomeric purity. [ABSTRACT FROM AUTHOR]

We report the development of a novel synthetic approach for the highly strained atrop‐Tyr C‐6‐to‐Trp N‐1′ linkage, which can be executed on a decagram scale using a modular strategy involving palladium‐catalyzed C−H arylation followed by Larock macrocyclization. The first total synthesis of lapparbin (1) was achieved by applying this synthetic strategy. Furthermore, the modular synthesis utilizing C−H arylation and Larock macrocyclization, discovered in the total synthesis of lapparbin (1), was demonstrated to be applicable to various arbitrary biaryl linkages, including non‐natural types. [ABSTRACT FROM AUTHOR]

In this work, we describe an efficient and modular method for enantiodivergent accessing P(V)‐stereogenic molecules by utilizing the catalytic atroposelective Catellani‐type C−H arylation/desymmetric intramolecular N‐arylation cascade reaction. The enantioselectivity of this protocol was proved to be tuned by the polarity of the solvent, thus providing a wide range of both chiral P(V)‐stereogenic enantiomers in moderate to good yields with good to excellent enantiomeric excesses. Noteworthy is that the strategy developed herein represents an unprecedented example of solvent‐dictated inversion of the enantioselectivity of P(V)‐stereogenic compounds. [ABSTRACT FROM AUTHOR]

A series of palladium‐N‐heterocyclic carbene complexes (2 a‐e) were synthesized from corresponding N‐heterocyclic carbene precursors (1 a‐e) in good yields. The structural analysis of all novel compounds was done by spectroscopic methods and elemental analysis was also performed to evaluate the purity of the complexes. Further confirmations of complexes 2 a‐d were provided by X‐ray crystallography technique. Under optimized reaction conditions, the catalytic activity of the palladium‐N‐heterocyclic carbene complexes was reviewed by direct arylation of furan‐2‐carboxaldehyde and 1‐methylpyrrole‐2‐carboxaldehyde with varied aryl halides. This arylation showed productive and selective reaction at the C5‐position of heteroaryl derivatives. [ABSTRACT FROM AUTHOR]

A library of neutral and cationic palladium complexes of cis‐chelating hetero‐dicarbene ligands have been prepared. These ligands contain two different NHC donors allowing for a wider degree of variation, and the impact of the distinct NHC units has been compared using various spectroscopic means. In addition, the catalytic activities of these complexes in the direct C‐H arylation of thiophenes with aryl halides were studied leading to the finding that the neutral dibromido complexes of the type [PdBr2(diNHC)] generally outperformed their cationic [Pd (NCMe)2(diNHC)](OTf)2 counterparts. More importantly, complexes containing more distinct NHC units give rise to superior catalysts due to an amplified "stereoelectronic asymmetry" within the complex. A preliminary photophysical study of some selected thiophene reaction products has been conducted as well. The ability to individually change each NHC donor in such dicarbene ligands allows for a better fine‐tuning of complex properties in search for superior catalysts. [ABSTRACT FROM AUTHOR]

Recently, PEPPSI‐type palladium‐complexes bearing N‐heterocyclic carbene (NHC) ligand have commonly been used as the effective catalysts in the direct arylation of heteroaromatic compounds. In most of previous studies catalyzed by such complexes, unsaturated ring carbene ligands such as benzo[d]imidazol‐2‐ylidene and imidazol‐2‐ylidene were used. However, the use of saturated ring carbene ligands such as 4,5‐dihydro‐imidazol‐2‐ylidene has been highly limited. Therefore, in this study, four novel 4,5‐dihydro‐1H‐imidazolium salts were synthesized as saturated ring carbene precursors. Then, well‐defined air‐ and moisture‐stable four novel PEPPSI‐type palladium‐complexes with 4,5‐dihydro‐imidazol‐2‐ylidene ligands were prepared. All synthesized carbene precursors and palladium‐complexes were structurally characterized by different spectroscopic and analytical techniques. Further structural characterization of two of the palladium‐complexes was performed by single‐crystal X‐ray diffraction. Next, the palladium‐complexes were tested in the direct arylation of azoles such as 4,5‐dimethylthiazole and 1‐methyl‐1H‐imidazole with (hetero)aryl halides in presence of 1 mol% catalyst loading at 120°C. The results showed that these novel palladium complexes are effective catalysts. [ABSTRACT FROM AUTHOR]

Pd(II)‐catalyzed enantioselective C−H activation has emerged as a versatile platform for constructing point, axial, and planar chirality. Herein, we present an unexpected discovery of a Pd‐catalyzed enantioselective cascade β,γ‐methylene C(sp3)−H diarylation of free carboxylic acids using bidentate chiral mono‐protected amino thioether ligands (MPAThio), enabling one‐step synthesis of a complex chiral 9,10‐dihydrophenanthrene scaffolds with high enantioselectivity. In this process, two methylene C(sp3)−H bonds and three C(sp2)−H bonds were activated, leading to the formation of four C−C bonds and three chiral centers in one pot. A plausible catalytic pathway starts with enantioselective β,γ‐dehydrogenation to form chiral β,γ‐cyclohexene. Intriguingly, this olefin serves as a norbornene‐type reagent (presumably assisted by the carboxyl directing effect), relaying two successive Catellani arylation reactions and a C−H arylation reaction to furnish chiral 9,10‐dihydrophenanthrenes along with meta‐selective homocoupling products of iodoarene. [ABSTRACT FROM AUTHOR]

A new approach for the preparation of a variety of 3-arylated 2-furoic acid derivatives has been developed. The approach involves selective Ru-catalyzed C3-H arylation of the furan moiety of readily available 2-furoyl-1-methylimidazole (using imidazole as a removable N-donor directing group), subsequent N-methylation, and nucleophilic substitution of the imidazole moiety with N, O, S, and C nucleophiles. [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]

We demonstrated that the combination of a Pd(0) catalyst and a water‐soluble TPPMS ligand has high activity for the direct arylation of readily available allylic alcohols in the Tsuji–Trost type cross‐coupling. Various organoboron reagents can be applied, enabling rapid access to the corresponding arylated products with a wide range of functional group tolerance. Kinetic studies revealed a first‐order rate dependence for the allylic alcohol, boronic acid, CsF and Pd(0)/TPPMS concentrations. A Hammett study found a slightly positive ρ value of 0.79, suggesting that a partial negative charge is generated on the aromatic ring of the aryl boronate in the rate‐determining transmetalation step. Based on several control experiments, we concluded that the transmetalation employing CsF would proceed via the oxo‐palladium mechanism. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Key Scientists Organoborons are commonly used building blocks for rapidly increasing molecular complexity. Although significant progress has been made in the selective functionalization of mono‐organoborons, the site‐selective functionalization of poly(organoborons) has attracted substantial interest in organic synthesis, pharmaceuticals, and agrochemicals due to the presence of multiple potential reaction sites. This review discusses various activation modes of the target C–B bond, with diverse transformations being achieved in both a selective and efficient manner. Recent advances in the catalytic selective transformations of 1,n‐diboronates through ionic and radical pathways are highlighted. Furthermore, we summarize the existing challenges and future research directions in this field.In 1993, Suzuki, Miyaura and coworkers developed a pioneering example of selective arylation towards cis‐1,2‐bis(boryl) alkenes, marking the inception of this field. The Morken group has made significant contributions to the asymmetric diboration of alkenes and realized elegant catalytic functionalization of these compounds since 2004. In 2016, Fernández and colleagues achieved the selective arylation of the internal C–B bond of tri(boronates). Since 2019, the Aggarwal group has developed efficient Giese‐type addition and selective arylation at the more substituted C–B bond of 1,2‐bis(boronic) esters through photoredox catalysis. The controllable regiodivergent alkynylation of 1,3‐bis(boronic) esters was developed by Gao and coworkers in 2023. Recently, Qin conducted elegant research on the programmable late‐stage functionalization of bridge‐substituted bicyclo[1.1.1]pentane (BCP) bis‐boronates. Since 2013, catalytic stereoselective transformations have been developed by several groups, including those led by Morken and Chen. This review summarizes the latest and most significant developments in this field since 1993. [ABSTRACT FROM AUTHOR]

Indole motifs are omnipresent in nature and can be found in many natural products as well as pharmaceuticals. It is for this reason synthetic transformations of indole have become a topic of interest for the organic and medicinal chemist community for decades. In this review, we have emphasized the functionalization of indoles via transition‐metal‐free approaches. This review touches on many aspects in different sub‐sections, which gives a proposition of the tactics employed for the functionalization of indoles and an overview of the road ahead. [ABSTRACT FROM AUTHOR]

α‐Aryl cyclocarbonyls are important building blocks in organic synthesis. While many methods have been developed for their synthesis, the use of readily available and inexpensive aryl chlorides as the arylating reagent remains rare. Herein, we report an α‐arylation of cyclic ketones with aryl chlorides under reductive electrophotocatalytic conditions. 2,6‐Diisopropylphenyl‐containing naphthalenemonoimide was identified as the optimal electrophotocatalyst, allowing for use of electron‐deficient as well as electron‐rich aryl chlorides under mild conditions. [ABSTRACT FROM AUTHOR]

Carbonyl addition serves as a strategically straightforward and versatile approach for synthesizing alcohols, which are often encountered within bioactive molecules. Herein, we present a ligand‐free, nickel‐catalyzed carbonyl addition process using organoboron reagents. This method enables efficient arylation of readily available ketones or aldehydes, affording a variety of tertiary and secondary alcohols. Key highlights of this protocol include the obviation of external ligands and the tolerance to many functional groups and heterocycles, thereby enhancing its practicality and utility in synthetic organic chemistry. [ABSTRACT FROM AUTHOR]

Herein, we report a cross‐coupling reaction between aryl sulfonyl chlorides and arylthianthrenium salts, catalyzed by palladium without ligand. This process involves the desulfonylative of aryl sulfonyl chlorides and pre‐ thianthrenation activation steps of aromatic hydrocarbons, leading to the selective formation of the biaryl compounds. The method demonstrates compatibility with various functional groups. Furthermore, the late‐stage functionalize‐tion of bioactive compounds underscores the favorable implications of this approach in the innovation of novel pharmaceutical agents. [ABSTRACT FROM AUTHOR]

Chemoselective arylation of 5-aminopyrazoles was performed through oxidative formation of orthoquinones from catechols catalyzed by Myceliophthora thermophila laccase (Novozym 51003), and subsequently nucleophilic attack of 5-aminopyrazole to the catechol intermediates. The C-4 arylated products were obtained under extremely mild conditions without the need for amine protection or halogenation of the substrates. From this method, 10 derivatives with moderate to good efficiency (42–94%) were prepared. [ABSTRACT FROM AUTHOR]

Directed Pd‐catalysed β‐(hetero)arylation of the 7‐oxabicyclo[2.2.1]heptane framework is described. Arylated products were formed in up to 99 % yield, and heteroarylated products in up to 88 % yield with complete diastereoselectivity. Different minor diarylated side products were formed, depending on whether electron deficient aryl or pyridyl iodides were used as the coupling partners. Cleavage of the 8‐aminoquinoline directing group provided small bridged compounds that may be of value in fragment based drug discovery. [ABSTRACT FROM AUTHOR]

Sulfur‐containing functional groups have garnered considerable attention due to their common occurrence in ligands, pharmaceuticals, and insecticides. Nevertheless, enantioselective synthesis of sulfilimines, particularly diaryl sulfilimines remains a challenging and persistent goal. Herein we report a highly enantio‐ and chemoselective cross–coupling of sulfenamides with aryl diazonium salt to construct diverse S(IV) stereocenters by Pd catalysis. Bisphosphine ligands bearing sulfinamide groups play a crucial role in achieving high reactivity and selectivity. This approach provides a general, modular and divergent framework for quickly synthesizing chiral sulfilimines and sulfoximines that are otherwise challenging to access. In addition, the origins of the high chemoselectivity and enantioselectivity were extensively investigated using density functional theory calculations. [ABSTRACT FROM AUTHOR]

A novel class of chain-like multidentate oxalamide ligands with additional coordinating groups was developed for the coupling of (hetero)aryl bromides with both alcohols and phenols under mild conditions. Introduction of oxygen atoms in N-alkyl chains is pivotal for the high catalytic efficiency and broad substrate versatility. [ABSTRACT FROM AUTHOR]

Herein, an operationally simple and mild protocol for defluorinative alkylation and arylation between thianthrenium salts and α-trifluoromethyl alkene with visible light to afford gem-difluoroolefins has been developed. The main feature of this method is avoiding the use of a metal photocatalyst, and an organic photocatalyst is unnecessary for the arylation reaction. In addition, thianthrene can also be recycled and transformed to thianthrenium salts without affecting the efficiency of these reactions. The protocol demonstrates excellent tolerance of functional groups and viable functionalization of late-stage natural products and pharmaceutically relevant molecules. [ABSTRACT FROM AUTHOR]

A metallaphotoredox-catalyzed synthesis of heterodiarylmethanes using mild reaction conditions, commercially available substrates, and bench-stable catalysts is demonstrated. Moderate yields are obtained, and further derivatization of the newly formed benzylic position is shown. [ABSTRACT FROM AUTHOR]

This account summarizes the impact that the quest for sustainability is having on the field of organic polyconjugate molecules and polymers for plastic (opto)electronics. While at the proof-of-concept level, the design criteria as well as the preferred synthetic strategies to access new and improved materials have been dominated by the need for performance. The ongoing transition from the lab environment to the industrial scale imposes strict limitations on the cost and overall environmental impact of new materials. We here summarize our efforts on the development of new design criteria and synthetic strategies aimed at improving sustainability – without compromising performance – in organic polyconjugated molecules. The article is composed of three sections: Introduction and motivation, sustainability through improved synthetic methods and through improved design. Outline 1 Introduction and Motivation 2 Sustainable Reaction Methods 2.1 The New Tools: Reactions in Aqueous Solution of Surfactants 2.2 Intrinsically More Sustainable Reactions: Direct Arylation 2.3 Sustainable Multistep Protocols: Combining Micellar, Solventless, and Mechanochemical Methods 3 Sustainability as a Design Criterion: De Novo Design 4 Conclusion [ABSTRACT FROM AUTHOR]

As "chemical chameleons," organosulfones have been widely applied in various desulfonylative functionalization reactions. However, the desulfonylative functionalization of (hetero)arylsulfones through the cleavage of inert C(sp2)–SO2 bonds remains a challenging and underexplored task. Over the past twenty years, the use of (hetero)arylsulfones as arylation reagents has gradually gained attention in diverse cross-coupling reactions under specific catalytic conditions, especially in transition metal-catalysis and photocatalysis chemistry. In this review, we discuss the representative accomplishments and mechanistic insights achieved in desulfonylative reactions of inactive C(sp2)–SO2 bonds in (hetero)arylsulfones, including: (i) transition-metal-catalyzed desulfonylative cross-coupling reactions and (ii) photo-/electrocatalytic radical desulfonylative coupling reactions. We anticipate that this review will provide an overall perspective in this area to a general audience of researchers and stimulate further innovative strategies for desulfonylative functionalization of inert arylsulfones. [ABSTRACT FROM AUTHOR]

The regioselective synthesis of 1‐alkyl‐5‐arylpyrazoles, which are potential drug candidates, has been difficult to achieve thus far. In this study, we developed an auto‐tandem Pd‐catalyzed C−C bond cleavage/Heck arylation of N‐cyclopropylhydrazones followed by cycloisomerization to afford diverse 1‐alkyl‐5‐arylpyrazoles. This step‐economical synthesis involves the cleavage of two C−H bonds and one C−C bond as well as the incorporation of directing groups. The identification of the reaction intermediates indicated an auto‐tandem catalytic pathway. The further transformation of products to 1,4,5‐substituted pyrazole and functional group transformations were carried out. [ABSTRACT FROM AUTHOR]

In this study, we explored the reactivity of meta‐trifluoromethanesulfonate (OTf) substituted diaryliodonium salts under alkaline conditions. Two distinct pathways with direct arylation of pyrrole derivatives and Diels‐Alder cycloaddition via aryne intermediates, have been found upon the relative alkalinity strength of potassium carbonates or hydroxides. This approach offers a straightforward and efficient route to synthesize heterocyclic aromatics under mild reaction conditions with tolerance of various functional groups. [ABSTRACT FROM AUTHOR]

The conceptual merger of relay catalysis with dynamic kinetic resolution strategy is reported to enable regio‐ and enantioselective C(sp3)‐H bond arylation of aliphatic alcohols, forming enantioenriched β‐aryl alcohols typically with >90 : 10 enantiomeric ratios (up to 98 : 2 er) and 36–74 % yields. The starting materials bearing neighbouring stereogenic centres can be converted to either diastereomer of the β‐aryl alcohol products, with >85 : 15 diastereomeric ratios determined by the catalysts. The reactions occur under mild conditions, ensuring broad compatibility, and involve readily available aryl bromides, an inorganic base, and commercial Ru‐ and Pd‐complexes. Mechanistic experiments support the envisioned mechanism of the transformation occurring through a network of regio‐ and stereoselective processes operated by a coherent Ru/Pd‐dual catalytic system. [ABSTRACT FROM AUTHOR]

Radical ipso‐substitution offers an alternative to organometallic approaches for biaryl synthesis, but usually requires stoichiometric reagents such as tributyltin hydride. Here, we demonstrate that visible light photoredox catalysis can be used for ipso‐biaryl synthesis, via a halogen‐atom transfer (XAT) regime. Using amide substrates that promote ipso‐ over unwanted ortho‐addition, we demonstrate smooth biaryl formation with no constraint on the electronic character of the migrating arene ring. The photoreaction can be combined in one operation to achieve a formal arylation of the inert aniline C−N bond. [ABSTRACT FROM AUTHOR]

Polythiophenes are the most appealing donor materials in organic solar cells (OSCs) due to their simple chemical structures. However, the top‐performance polythiophenes are typically synthesized via Stille polycondensation, which is problematic due to significant toxicity and poor atom economy. By contrast, direct arylation polycondensation (DArP) is an eco‐friendly, and atom‐efficient alternative for synthesizing conjugated polymers, while the best efficiency for DArP‐derived polythiophenes is below 12%. This study reports a series of polythiophene‐based donors synthesized via DArP. Among these, PT4F‐Th reaches a power conversion efficiency (PCE) of 16.4%, which not only matches the current record for polythiophene‐based donor materials, but also marks the highest PCE achieved by DArP‐derived donors to date. The superior performance of PT4F‐Th is largely attributed to its optimal temperature‐dependent aggregation behavior and moderate miscibility with acceptors, along with the highest crystallinity among the candidates, resulting in the most favorable blend film morphology. This study underscores the significant potential of DArP‐derived polythiophenes in developing high‐performance and eco‐friendly OSCs. [ABSTRACT FROM AUTHOR]

Benzyne derived from hexadehydrogenated Diels Alder (HDDA) reactions was found to be an efficient hydrosilylation acceptors. Various silanes can react smoothly with HDDA‐derived benzyne to give the arylation products. Lewis acid such as boron trifluoride etherate can accelerate these hydrosilylation reactions. Polyhydromethylsiloxane (PHMS), a widely used organosilicon polymer, was also successfully modified using our method. About 5 % of Si−H bonds in the polymer were inserted by benzynes, giving a functional PHMS with much more solubility in methanol and with a blue‐emitting fluorescence behavior. Mechanism research shows that the insertion of benzyne into the Si−H bond probably undergoes a synergistic pathway, which is quite different from the traditional radical‐initiated hydrosilylation or transition‐metal‐catalyzed hydrosilylation. [ABSTRACT FROM AUTHOR]

Herein, the use of economically and environmentally friendly bis(pinacolato)diboron (B2Pin2) is described as a non‐metallic reductant in mediating Ni‐catalyzed C(sp3)–C(sp2) reductive cross‐coupling of alkyl electrophiles with aryl/vinyl halides. This method exhibits excellent suitability for heteroaryl halides and alkyl halides/Katritzky salts. The present study is compatible with an in situ halogenation of alcohol method, allowing for selective mono‐functionalization of diols and bio‐relevant alcohols (e.g., carbohydrates). The use of B2Pin2 shows potential for easy scalability without introducing additional metal impurities into the products. It is observed for the first time in the realm of cross‐electrophile coupling chemistry that B2Pin2 can sever as a reductant to reduce NiII to Ni0. This mechanistic insight may inspire the development of new reductive bond‐forming methodologies that can otherwise be difficult to achieve with a metal reductant. [ABSTRACT FROM AUTHOR]

[Display omitted] Plasmon-mediated chemical reaction (PMCR) is a highly attractive field of research. Here we report in situ surface-enhanced Raman spectroscopic (SERS) monitoring of plasmonic-mediated S S bond-forming reaction. The reaction is thought to be a self-coupling reaction proceeding by photoinduced aromatic S C bond arylation. Surprisingly, the S C arylation and S S coupling are found to be occurred on both partially oxidized silver and silver nanoparticles. The results demonstrated that silver oxide or hydroxide and small molecule donor sacrifice agent played a crucial role in the reaction. This work facilitates the in-situ manipulation and characterization of the active silver electrode interface in conjunction with electrochemistry, and also establishes a promising new guideline for surface plasmon resonance photocatalytic reactions on metal nanostructures with high efficiency. [ABSTRACT FROM AUTHOR]

Copper-catalysed intramolecular Ullman arylation has been frequently used to synthesise benzoxazoles and benzothiazoles. Despite widespread use, investigations into the mechanism and speciation of copper-containing complexes relevant to the catalytic pathway have remained relatively limited. Accordingly, this study aims to elucidate the structural details of potential copper(I) intermediates through the analysis of their solid-state structures using X-ray crystallography, while also investigating the reactivities of these complexes. Five novel copper complexes are reported which are formed prior to the aryl halide activation step and feature distinct aggregation modes based on either Cu4N4O4C4 or Cu4N4S4C4 clusters. [ABSTRACT FROM AUTHOR]

Direct structural modification of small‐molecule fluorophores represents a straightforward and appealing strategy for accessing new fluorescent dyes with desired functionalities. We report herein a general and efficient visible‐light‐mediated method for the direct C−H functionalization of BODIPY, an important fluorescent chromophore, using readily accessible and bench‐stable aryl and alkenylthianthrenium salts. This practical approach operates at room temperature with extraordinary site‐selectivity, providing a step‐economical means to construct various valuable aryl‐ and alkenyl‐substituted BODIPY dyes. Remarkably, this protocol encompasses a broad substrate scope and excellent functional‐group tolerance, and allows for the modular synthesis of sophisticated symmetrical and asymmetrical disubstituted BODIPYs by simply employing different combinations of thianthrenium salts. Moreover, the late‐stage BODIPY modification of complex drug molecules further highlights the potential of this novel methodology in the synthesis of fluorophore‐drug conjugates. [ABSTRACT FROM AUTHOR]

A magnetically isolable iron oxide nanoparticles is introduced as an efficient heterogeneous photocatalyst for non‐directed C−H arylation employing aryl diazonium salts as the aryl precursors. This first‐row transition metal‐based photocatalyst revealed versatile activities and is applicable to a wide range of substrates, demonstrating brilliant efficacy and superior recyclability. Detailed catalytic characterization describes the physical properties and redox behavior of the Fe‐catalyst. Adequate control experiments helped to establish the radical‐based mechanism for the C−H arylation. [ABSTRACT FROM AUTHOR]

Herein, we describe a visible light‐induced C(sp2)−H arylation method for quinoxalin‐2(1H)‐ones and coumarins using iodonium ylides without the need for external photocatalysts. The protocol demonstrates a broad substrate scope, enabling the arylation of diverse heterocycles through a simple and mild procedure. Furthermore, the photochemical reaction showcases its applicability in the efficient synthesis of biologically active molecules. Computational investigations at the CASPT2//CASSCF/PCM level of theory revealed that the excited state of quinoxalin‐2(1H)‐one facilitates electron transfer from its π bond to the antibonding orbital of the C−I bond in the iodonium ylide, ultimately leading to the formation of an aryl radical, which subsequently participates in the C−H arylation process. In addition, our calculations reveal that during the single‐electron transfer (SET) process, the C−I bond cleavage in iodonium ylide and new C−C bond formation between resultant aryl radical and cationic quinoxaline species take place in a concerned manner. This enables the arylation reaction to efficiently proceed along an energy‐efficient route. [ABSTRACT FROM AUTHOR]

Site-selective C(sp3)–H arylation is an appealing strategy to synthesize complex arene structures but remains a challenge facing synthetic chemists. Here we report the use of photoredox-mediated hydrogen atom transfer (HAT) catalysis to accomplish the site-selective α-C(sp3)–H arylation of dialkylamine-derived ureas through 1,4-radical aryl migration, by which a wide array of benzylamine motifs can be incorporated to the medicinally relevant systems in the late-stage installation steps. In contrast to previous efforts, this C–H arylation protocol exhibits specific site-selectivity, proforming predominantly on sterically more-hindered secondary and tertiary α-amino carbon centers, while the C–H functionalization of sterically less-hindered N-methyl group can be effectively circumvented in most cases. Moreover, a diverse range of multi-substituted piperidine derivatives can be obtained with excellent diastereoselectivity. Mechanistic and computational studies demonstrate that the rate-determining step for methylene C–H arylation is the initial H atom abstraction, whereas the radical ipso cyclization step bears the highest energy barrier for N-methyl functionalization. The relatively lower activation free energies for secondary and tertiary α-amino C–H arylation compared with the functionalization of methylic C–H bond lead to the exceptional site-selectivity. Site-selective C(sp3)–H arylation is an appealing strategy to synthesize complex arene structures but remains a challenge facing synthetic chemists. Here the authors report the use of photoredox-mediated hydrogen atom transfer (HAT) catalysis to accomplish the site-selective α-C(sp3)–H arylation of dialkylamine-derived ureas through 1,4-radical aryl migration. [ABSTRACT FROM AUTHOR]

In this study, novel Cu@CuFe2O4 nanoparticles were prepared by virtue of a simple method. By utilizing a compatible system involving N‐chlorosuccinimide (NCS) as the chlorine source and Cu@CuFe2O4 magnetic nanoparticles (NPs) as recyclable catalyst, we present a novel and practical method for directly obtaining aryl α,α‐dichloroketones in aqueous trifluoroethanol (TFE). The catalyst was recovered and reused up to five times with no significant decrease in activity. The current study provides a foundational raw material for the subsequent synthesis of chlorinated functional molecules, which is achieved through a mild transformation of arylalkynes using readily available commercial feedstocks and exhibiting good tolerance with various substituents on the aromatic ring, including the aliphatic alkyne. This novel heterogeneous catalyst may be used in numerous industrial applications because of its merits, such as considerable recyclability, low requirement for catalyst loading, cost‐effectiveness, and ease of handling. [ABSTRACT FROM AUTHOR]

BODIPYs have a well‐established role in biological sciences as chemosensors and versatile biological markers due to their chemical reactivity, which allows for fine‐tuning of their photophysical characteristics. In this work, we combined the unique reactivity of arylazo sulfones with the advantages of a “sunflow” reactor to develop a fast, efficient, and versatile method for the photochemical arylation of BODIPYs and other chromophores. This approach resulted in red‐shifted emitting fluorophores due to extended electronic delocalization at the 3‐ and 5‐positions of the BODIPY core. This method represents an advantageous approach for BODIPY functionalization compared to existing strategies. [ABSTRACT FROM AUTHOR]

Metal‐catalyzed enantioselective conjugate arylations of electron‐poor alkenes are highly selective processes for C(sp2)−C(sp3) bond formation. δ‐Selective hydroarylations of electron‐poor 1,3‐dienes are less well developed and reactions that deliver high enantioselectivity while giving single alkene isomer products are elusive. Here we report the Rh‐catalyzed δ‐arylation of aryl‐substituted 1,3‐dienes that gives nearly exclusive Z‐1,4‐addition products (generally with >95 : 5 positional and geometrical selectivity). This remote functionalization provides access to chiral diarylated alkenes from readily available precursors poised for further functionalization, including in the synthesis of bioactive molecules. Mechanistic studies suggest that protonolysis of a Rh‐allyl intermediate generated by diene insertion into a Rh‐aryl is the turnover limiting step and occurs by an inner‐sphere proton transfer pathway. [ABSTRACT FROM AUTHOR]

A selective direct arylation of the different Csp2‐H bonds of imidazo[2,1‐b]thiazole with (hetero) aryl halides can be achieved simply by switching from a palladium catalyst system to the use of stoichiometric amounts of copper. The observed selectivity, also rationalized by DFT calculations, can be explained by a change in the mechanistic pathways between electrophilic palladation and base‐promoted C−H metalation. [ABSTRACT FROM AUTHOR]

An efficient and broadly applicable rhodium‐catalyzed direct ortho‐arylation of anilines with aryl iodides relying on readily available aminophosphines as traceless directing groups is reported. Its scope and functional group compatibility were both found to be quite broad as a large variety of both aminophosphines and (hetero)aryl iodides, including complex ones, could be utilized. The ortho‐arylated anilines could be obtained in high average yields, without any competing diarylation and with full regioselectivity, which constitutes a major step forward compared to other processes. The reaction is moreover not limited to aryl iodides, as an aryl bromide and a triflate could be successfully used, and could be extended to diarylation. Mechanistic studies revealed the key and unique role of the aminophosphine, acting not only as a substrate but also as a ligand for the rhodium catalyst. [ABSTRACT FROM AUTHOR]

An electrochemical radical Truce Smiles rearrangement of N‐allylbenzamides is documented herein. The selective 1,4‐aryl migration was triggered by the radical fluoromethylation of the alkene providing a direct route to fluoro derivatives of the highly privileged β‐arylethylamine pharmacophore. This practical transformation utilizes readily available starting materials and employs an electrical current to drive the oxidative process under mild reaction conditions. It accommodates a variety of migratory aryl groups with different electronic properties and substitution patterns. Careful selection of the protecting group on the nitrogen atom of the N‐allylbenzamide is crucial to outcompete the undesired 6‐endo cyclization and achieve high level of selectivity towards the 1,4‐aryl migration. DFT calculations support the reaction mechanism and unveil the origin of selectivity between the two competitive pathways. [ABSTRACT FROM AUTHOR]

Palladium‐catalyzed enantioselective C(sp3)−H functionalization reactions has attracted considerable attention due to its ability for the synthesis of enantiomerically enriched molecules and stimulation of novel retrosynthetic disconnections. Understanding the reaction mechanism, especially the stereochemical process of the reaction, is crucial for the rational design of more efficient catalytic systems. Previously, we developed a Pd(II)/sulfoxide‐2‐hydroxypridine (SOHP) catalytic system for asymmetric C(sp3)−H functionalization reactions. In this study, we focused on unraveling the chemistry of chiral palladacycles involved in the Pd(II)‐catalyzed enantioselective C(sp3)−H functionalization. We have isolated key palladacycle intermediates involved in the enantioselective β‐C(sp3)−H arylation of carboxylic acids catalyzed by the Pd(II)/SOHP system. These palladacycles, exhibiting ligand‐induced chirality, provided a significant opportunity to investigate the stereochemical process and the ligand effect in this asymmetric C−H functionalization. Our investigation provided direct evidence for the C−H palladation step as the enantioselectivity‐determining step, which forms diastereomeric palladacycles that exhibited preservation of chirality in the functionalization step. DFT calculations provided insights into the chiral induction in palladacycle formation. This work highlights the value of chiral palladacycle chemistry in offering mechanistic insights into the Pd(II)‐catalyzed asymmetric C(sp3)−H functionalization reactions. [ABSTRACT FROM AUTHOR]