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Functionalizable directing groups (DGs) are highly desirable in C−H activation chemistry. The nitrone DGs are explored in rhodium(III)-catalyzed C−H activation of arenes and couplings with cyclopropenones. N-tert-butyl nitrones bearing a small ortho substituent coupled to afford 1-naphthols, where the nitrone acts as a traceless DG. In contrast, coupling of N-tert-butyl nitrones bearing a bulky ortho group follows a C−H acylation/[3+2] dipolar addition pathway to give bicyclics. The coupling of N-arylnitrones follows the same acylation/[3+2] addition process but delivers different bicyclics. [ABSTRACT FROM AUTHOR]

Abstract: Novel air-stable C 2-symmetric tetrasubstituted ruthenocene-based ligands were readily synthesized and used for palladium-catalyzed asymmetric allylic substitution showing excellent enantioselectivity and high catalytic activity. [Copyright &y& Elsevier]

[Display omitted] Traditional semiconductor materials such as metal-oxide-based photoelectrodes have been extensively explored for energy and environmental applications. However, their performance is hindered by poor light absorption, high charge recombination rates, and low surface kinetics. The incorporation of metal–organic framework (MOF) and plasmonic structures into semiconductors is one of the most promising strategies to achieve performances beyond those of bare MOF and/or conventional semiconductors. This review summarises the rational design of semiconductor-based photoelectrodes incorporating MOFs and plasmonic metals for hybrid photoelectrochemical catalysis and photocatalysis, with a wide variety of parameters including photoactivity, conductivity, catalytic property, surface morphology, porous architecture and bandgap alignment. Moreover, applications of this new generation of composite photoelectrodes in water splitting, CO 2 reduction and pollution degradation are discussed in detail. The challenges and prospects of plasmonic MOF nanocomposites in eco-friendly and cost-efficient technologies for practical applications in water splitting, CO 2 reduction and environmental remediation are also highlighted. [ABSTRACT FROM AUTHOR]

In the presence of Au(I) the C-H alkynylation of 2-pyridones occurs at the most electron-rich 5-position via an electrophilic alkynylation pathway while the selectivity is switched to the 6-position under assistance of an N-chelation group when a Rh(III) catalyst is employed. [ABSTRACT FROM AUTHOR]

The first examples of a Rh(III)-catalyzed electrophilic C-H trifluoromethylation of indoles are described. [ABSTRACT FROM AUTHOR]

The rhodium(III)-catalyzed C-H hyperiodination of electron-poor arenes proceeds under chelation assistance at room temperature with high regioselectivity and functional group compatibility. [ABSTRACT FROM AUTHOR]

The scalable reaction between aryl boronic acids and aryl nitroalkenes proceeds with high yields and enantioselectivities, but fails using alkyl nitroalkenes. [ABSTRACT FROM AUTHOR]

Chemical equations are presented for the article "Pd-Catalyzed Asymmetric Allylic Amination Using Easily Accessible Metallocenyl P,N-Ligands" by H. Wu and colleagues published in the journal "Organic & Biomolecular Chemistry" in 2015.

A mild and efficient synthesis of ynones using Ir(III) or Rh(III) catalysis is presented. [ABSTRACT FROM AUTHOR]

An efficient, mild, and ortho selective Rh- and Ir-catalyzed C-H alkynylation of diversified arenes using hypervalent iodine-alkyne reagents is developed. [ABSTRACT FROM AUTHOR]

The first regioselective Rh-catalyzed C-H azidation and nitration of arenes is developed. [ABSTRACT FROM AUTHOR]

An abstract of the article "Ir(III)-Catalyzed C-H Alkynylation of Arenes under Chelation Assistance" by G.D. Tang and colleagues is presented.

Selective trifluoromethylthiolation of electron-rich arenes and olefins is achieved in the presence of a Lewis acid catalyst such as Fe(III) or Au(III). [ABSTRACT FROM AUTHOR]

Abstract: A series of hexadentate 8-quinolinolato manganese(III) complexes were synthesized and proven to own a distorted octahedral geometry via elemental analysis, solid UV–vis spectroscopy and Hartree–Fock/3-21G+ calculation. These Mn(III) complexes were found to be more efficient than their corresponding tetradentate 8-quinolinolato manganese(II) and salen-MnIIIOAc for the oxidation of alcohols in acetone medium, being due to their special hexadentate binding structures that could open an axial Mn form the more active pentadentate structures in the presence of aqueous hydrogen peroxide, as supported by UV–vis spectra. The halogen substituents in ligand''s aryl ring could significantly enhance the catalytic activities and 5-chloro-7-iodo-8-quinolinolato manganese(III) gave the highest turnover number (TON). A reasonable mechanism for the present catalytic system was proposed. [Copyright &y& Elsevier]

Abstract: Novel hexadentate binding 8-quinolinolato manganese(III) complexes were proposed and conveniently synthesized for the epoxidation of olefins with aqueous hydrogen peroxide in water–acetone media with ammonium acetate and acetic acid as additives. The catalytic efficiencies of the suggested catalysts were found to be obviously superior to the traditional tetradentate salen–MnIIICl, due to their special hexadentate binding structures that could be easily converted to the corresponding pentadentate with pendant hydroxyl groups by opening an axial Mn the reaction media, as supported by UV–vis spectra, in situ cyclic voltammetry, and quartz crystal microbalance characterizations. [Copyright &y& Elsevier]

The reaction is sensitive to the steric influence of the substituent at the C3-position. [ABSTRACT FROM AUTHOR]