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Atropisomeric phosphines hold considerable significance in asymmetric catalysis, yet their synthesis presents a formidable challenge owing to intricate multistep procedures. In this context, a groundbreaking methodology has been presented for their preparation. This innovative approach entails an atroposelective rhodium‐catalyzed C−H activation employing aryl and heteroaryl halides, chelated by a P(III) center. The essence of this strategy lies in its ability to directly construct chiral phosphine ligands in a single step, thereby exhibiting exceptional efficiency in terms of atom and redox economy. Illustrative examples serve to demonstrate the immense potential of in situ‐formed ligands in asymmetric catalysis. Mechanistic experiments have further provided invaluable insights into this transformation. [ABSTRACT FROM AUTHOR]

Transition‐metal‐catalyzed enantioselective addition of aryl organometallic reagents to imines has emerged as one of the most powerful tools for the formation of optically active diarylmethylamines. Here, we report the first asymmetric reductive (hetero)arylations of imines using aryl and heteroaryl halides enabled by a chiral cobalt‐bisphosphine catalyst. This approach shows good functional group compatibility and complements the reported strategy without use of organometallic reagents. Mechanistic investigations supported that aryl‐cobalt, instead of an arylzinc reagent, was formed in situ in this reductive aryl‐addition event. [ABSTRACT FROM AUTHOR]

The widespread use of phosphine ligand libraries is frequently hampered by the challenges associated with their modular preparation. Here, we report a protocol that appends arenes to arylphosphines to access a series of biaryl monophosphines via rhodium-catalyzed P(III)-directed ortho C–H activation, enabling unprecedented one-fold, two-fold, and three-fold direct arylation. Our experimental and theoretical findings reveal a mechanism involving oxidative addition of aryl bromides to the Rh catalyst, further ortho C–H metalation via a four-membered cyclometalated ring. Given the ready availability of substrates, our approach opens the door to developing more general methods for the construction of phosphine ligands. The widespread use of biaryl monophosphines is frequently hampered by the challenges associated with their modular preparation. Here, the authors report a protocol that appends arenes to arylphosphines to access a series of these compounds via rhodium-catalysed P(III)- directed ortho C–H activation, enabling one-fold, two-fold, and threefold direct arylation. [ABSTRACT FROM AUTHOR]

The formation of C–aryl bonds has been the focus of intensive research over the last decades for the construction of complex molecules from simple, readily available feedstocks. Traditionally, these strategies involve the coupling of organohalides (I, Br, Cl) with organometallic reagents (Mg, Zn, B, Si, Sn,...) such as Kumada–Corriu, Negishi, Suzuki–Miyaura, Hiyama and Sonogashira cross-couplings. More recently, alternative methods have provided access to these products by reactions with less reactive C–Het (F, O, S, N) and C–C bonds. Compared to traditional methods, the direct cleavage and arylation of these chemical bonds, the essential link in accessible feedstocks, has become increasingly important from the viewpoint of step-economy and functional-group compatibility. This comprehensive review aims to outline the development and advances of this topic, which was organized into (1) C–F bond arylation, (2) C–O bond arylation, (3) C–S bond arylation, (4) C–N bond arylation, and (5) C–C bond arylation. Substantial attention has been paid to the strategies and mechanistic investigations. We hope that this review can trigger chemists to discover more efficient methodologies to access arylation products by cleavage of these C–Het and C–C bonds. [ABSTRACT FROM AUTHOR]

Rhodium‐catalyzed C7‐selective decarbonylative arylation, olefination, and methylation of indoles with carboxylic acids or anhydrides by C−H and C−C bond activation have been developed. Furthermore, C7‐acylation products can also be generated selectively at a lower reaction temperature in the developed system. The key to the high reactivity and regioselectivity of this transformation is the appropriate choice of an indole N‐PtBu2 chelation‐assisted group. This method has many advantages, including easy access and removal of the directing group, the use of cheap and widely available coupling agents, no requirement of an external ligand or oxidant, a broad substrate scope, high efficiency, and the formation of a sole regioisomer. 4 in 1: A PIII‐chelation‐assisted group coordinates to the rhodium(I) catalyst and directs C−H activation to the indole C7 position, which then allows for a series of selective C−H functionalizations with carboxylic acids or anhydrides. [ABSTRACT FROM AUTHOR]

Abstract: A straightforward method was developed for construction of aromatic compounds with a triphenylene core. The method involves Pd‐catalyzed annulative dimerization of o‐iodobiaryl compounds by double C−I and C−H bond cleavage steps. Simple reaction conditions are needed, requiring neither a ligand nor an oxidant, and the reaction tolerates a wide range of coupling partners without compromising efficiency or scalability. Significantly, the tetrachloro‐substituted synthon, 1,6,11‐trichloro‐4‐(4‐chlorophenyl)triphenylene, can be generated and used to prepare a series of fully fused, small graphene nanoribbons by a late‐stage arylation with arylboronic acids and a subsequent Scholl reaction. The synthetic strategy enables bottom‐up access to extended π‐systems in a controlled manner. [ABSTRACT FROM AUTHOR]

Recent advances in transition metal-catalyzed selective C–H functionalization of indoles have garnered tremendous attention. Great efforts have been devoted to C2 and C3 arylation because of the inherent reactivity of the pyrrole ring. Until recently, elegant methods have been developed to enable selective direct arylation on the benzenoid moiety at C4, C5, C6, and C7. This review highlights the contributions made in benzenoid direct arylation of indoles and presents their potential in organic synthesis. [ABSTRACT FROM AUTHOR]

Modification of commercially available monophosphine ligands with either aryl bromides or chlorides by rhodium(I)-catalyzed, tertiary phosphine directed C−H activation is described. A series of ligand libraries containing mono- and diaryl-substituted groups, having different steric and electronic properties, were obtained in high yields. Based on the outstanding properties of their parent scaffolds, the modified ligands have been found to be powerful in organic reactions. [ABSTRACT FROM AUTHOR]

An effective and practical strategy has been established for the direct and site-selective arylation of indoles at the C4 and C5 positions with the aid of a readily accessible, cheap, and removable pivaloyl directing group at the C3 position. This transformation shows good functional-group tolerance and could serve as a powerful synthetic tool for the synthesis of medicinally relevant compounds. This method and those developed in previous research together enable the regiocontrolled direct arylation of indole at each C−H bond without prefunctionalization of the reactive sites. [ABSTRACT FROM AUTHOR]

The article presents a scientific method to obtain synthesis of fluorenones through quaternary ammonium salt promoted intramolecular dehydrogenative arylation of aldehydes. Chemical equations and reactions for gram-scale synthesis, xanthone synthesis, and bianthronyl synthesis are given in the article.

With the aim to obtain biologically interesting substances, fluorenones (II), (IV), (VI)/(VII) and related compounds such as (IX), and (XI)/(XII) are prepared via an intramolecular oxidative acylation process. [ABSTRACT FROM AUTHOR]

A direct ortho-arylation of arenes and olefins by diaryliodonium salts yields biaryls and aryl alkenes, resp., under mild reaction conditions and with a high tolerance of functional groups including halides. [ABSTRACT FROM AUTHOR]

Key to the regioselectivity is the choice of the phosphinoyl directing group and a pyridine-type ligand in the presence of Pd(OAc)2 as catalyst. [ABSTRACT FROM AUTHOR]

This protocol provides a powerful tool for late stage functionalization of complex molecules. [ABSTRACT FROM AUTHOR]

The catalytic system is capable of activating aryl and benzyl ammonium bonds for C-N borylation to produce a variety of organoborates. [ABSTRACT FROM AUTHOR]