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Herein, we report a reductive cross‐coupling reaction of α‐oxy halides, simply generated from aldehydes, with a series of C(sp2)‐ and C(sp)‐electrophiles. A wide range of aryl and heteroatom aryl halides, vinyl bromides, alkynyl bromides, and acyl chlorides react with unhindered and hindered aldehyde‐derived α‐oxy halides by providing protected alcohols as well as α‐hydroxy ketones. Noteworthy, the reductive couplings are achieved not only through thermal catalysis with the use of metal reductants but also by photocatalysis, electrochemistry, and mechanochemistry. The unrestricted interchange of the four strategies indicates their underlying mechanistic similarities. The generation of NiI intermediate is proposed to be the key point for ketyl radical formation via a single‐electron transfer (SET) event, which was rationalized by an array of control experiments and density functional theory (DFT) calculations. [ABSTRACT FROM AUTHOR]

Herein, we report a reductive cross‐coupling reaction of α‐oxy halides, simply generated from aldehydes, with a series of C(sp2)‐ and C(sp)‐electrophiles. A wide range of aryl and heteroatom aryl halides, vinyl bromides, alkynyl bromides, and acyl chlorides react with unhindered and hindered aldehyde‐derived α‐oxy halides by providing protected alcohols as well as α‐hydroxy ketones. Noteworthy, the reductive couplings are achieved not only through thermal catalysis with the use of metal reductants but also by photocatalysis, electrochemistry, and mechanochemistry. The unrestricted interchange of the four strategies indicates their underlying mechanistic similarities. The generation of NiI intermediate is proposed to be the key point for ketyl radical formation via a single‐electron transfer (SET) event, which was rationalized by an array of control experiments and density functional theory (DFT) calculations. [ABSTRACT FROM AUTHOR]

Metallaphoto-catalysis has been established as a robust platform for efficient construction of a range of chemical bonds. Moreover, transformation of native functionalities such as C(sp3)–H bonds to produce functional molecules represents one of the most attractive strategies in organic synthesis. Merging two powerful methodologies, metallaphoto-catalyzed benzylic and allylic C(sp3)–H bond functionalizations provide a series of general and mild approaches for diversification of alkylbenzenes and alkenes. [ABSTRACT FROM AUTHOR]

A new cross‐coupling of trifluoromethyl arenes has been realized via multiphoton photoredox catalysis. Trifluoromethyl arenes were demonstrated to undergo selective mono‐defluorinative alkylation under mild reaction conditions providing access to a series of valuable α,α‐difluorobenzylic compounds. The reaction shows broad substrate scope and general functional group tolerance. In addition to the electron‐deficient trifluoromethyl arenes that are easily reduced to the corresponding radical anion, more challenging electron‐rich substrates were also successfully applied. Steady‐State Stern‐Volmer quenching studies indicated that the trifluoromethyl arenes were reduced by the multiphoton excited Ir‐based photocatalyst. [ABSTRACT FROM AUTHOR]

Alkynes are an important class of organic molecules due to their utility as versatile building blocks in synthesis. Although efforts have been devoted to the difunctionalization of alkynes, general and practical strategies for the direct hydroalkylation and alkylarylation of terminal alkynes under mild reaction conditions are less explored. Herein, we report a photoredox/nickel dual‐catalyzed anti‐Markovnikov‐type hydroalkylation of terminal alkynes as well as a one‐pot arylalkylation of alkynes with alkyl carboxylic acids and aryl bromides via a three‐component cross‐coupling. The results indicate that the transformations proceed via a new mechanism involving a single‐electron transfer with subsequent energy‐transfer activation pathways. Moreover, steady‐state and time‐resolved fluorescence‐spectroscopy measurements, density functional theory (DFT) calculations, and wavefunction analysis have been performed to give an insight into the catalytic cycle. [ABSTRACT FROM AUTHOR]

Alkynes are an important class of organic molecules due to their utility as versatile building blocks in synthesis. Although efforts have been devoted to the difunctionalization of alkynes, general and practical strategies for the direct hydroalkylation and alkylarylation of terminal alkynes under mild reaction conditions are less explored. Herein, we report a photoredox/nickel dual‐catalyzed anti‐Markovnikov‐type hydroalkylation of terminal alkynes as well as a one‐pot arylalkylation of alkynes with alkyl carboxylic acids and aryl bromides via a three‐component cross‐coupling. The results indicate that the transformations proceed via a new mechanism involving a single‐electron transfer with subsequent energy‐transfer activation pathways. Moreover, steady‐state and time‐resolved fluorescence‐spectroscopy measurements, density functional theory (DFT) calculations, and wavefunction analysis have been performed to give an insight into the catalytic cycle. [ABSTRACT FROM AUTHOR]

Chemical transformations based on cascade reactions have the potential to simplify the preparation of diverse and architecturally complex molecules dramatically. Herein, we disclose an unprecedented and efficient method for the cross‐coupling of radical precursors, dienes, and electrophilic coupling partners via a photoredox‐ and nickel‐enabled cascade cross‐coupling process. The cascade reaction furnishes a diverse array of saturated carbo‐ and heterocyclic scaffolds, thus providing access to a quick gain in C−C bond saturation. [ABSTRACT FROM AUTHOR]

Chemical transformations based on cascade reactions have the potential to simplify the preparation of diverse and architecturally complex molecules dramatically. Herein, we disclose an unprecedented and efficient method for the cross‐coupling of radical precursors, dienes, and electrophilic coupling partners via a photoredox‐ and nickel‐enabled cascade cross‐coupling process. The cascade reaction furnishes a diverse array of saturated carbo‐ and heterocyclic scaffolds, thus providing access to a quick gain in C−C bond saturation. [ABSTRACT FROM AUTHOR]

The synergistic catalysis in the catalytic hydrogenolysis (CH) of lignin and its model compounds over a Ni-Ru/AC bimetallic surface was well established. The Ni-Ru/AC exhibits excellent activity and stability for catalytic hydrogenolysis of lignin and its model compound. The additions of Ru into supported Ni/AC can not only improve the overall reactants conversion, but also modify the product distribution. The apparent activation energy (E a) of BPE hydrogenolysis over Ni-Ru/AC is measured approximately to be 18.3 kJ/mol. This value is considerably lower than the values measured for monometallic Ni/AC (42.4 kJ/mol). Additionally, the turnover frequency (TOF) of Ni-Ru/AC (62.7 h−1) was much higher than that of Ni/AC (5.1 h−1). In case of CH of lignin, Ni-Ru/AC gave better total liquid yield and higher relative content of main aromatic monomers. The enhancement in the overall hydrogenolysis activity of reactants over bimetallic Ni-Ru/AC is related to the synergistic effect of Ni and Ru. Various characterization methods (XRD, XPS, TEM-EDS, SEM-EDX and BET) are performed to elucidate the formation of synergistic effect. This synergistic effect could originate from the generation of additional surface active sites, small size of metal particles and high dispersion of metal particles. Unlabelled Image • A synergic effect between Ru and Ni in bimetallic catalyst was observed. • The turnover frequency and activation energies of catalysts were calculated. • Proposed mechanism of cleavage C O of BPE over bimetallic Ni Ru catalyst • Bimetallic Ni Ru showed higher activity for CH of lignin and its model compound. [ABSTRACT FROM AUTHOR]

The peroxynitrite anion (ONOO−) is closely associated with many diseases and the creation of ONOO− donors is an essential means of understanding its pathophysiological functions. However, it is challenging to develop ONOO− donors due to the difficulties in simultaneously producing highly reactive and short‐lived nitric oxide (NO) and superoxide anion (O2⋅−). Here, we report a novel strategy for constructing ONOO− donors by combining near‐infrared (NIR)‐mediated type I photosensitization and photoredox catalysis. The key design using a Nile blue analogue that can serve as both a type I photosensitizer and a metal‐free photocatalyst. Intriguingly, the formation of O2⋅− via type I photosensitization avoids oxygen interference and instead activates nitrobenzofurazan‐based NO donors via oxygen‐tolerant NIR photoredox catalysis. The simultaneous release of O2⋅− and NO leads to ONOO− release, showing both antibacterial and antibiofilm activities. [ABSTRACT FROM AUTHOR]

The peroxynitrite anion (ONOO−) is closely associated with many diseases and the creation of ONOO− donors is an essential means of understanding its pathophysiological functions. However, it is challenging to develop ONOO− donors due to the difficulties in simultaneously producing highly reactive and short‐lived nitric oxide (NO) and superoxide anion (O2⋅−). Here, we report a novel strategy for constructing ONOO− donors by combining near‐infrared (NIR)‐mediated type I photosensitization and photoredox catalysis. The key design using a Nile blue analogue that can serve as both a type I photosensitizer and a metal‐free photocatalyst. Intriguingly, the formation of O2⋅− via type I photosensitization avoids oxygen interference and instead activates nitrobenzofurazan‐based NO donors via oxygen‐tolerant NIR photoredox catalysis. The simultaneous release of O2⋅− and NO leads to ONOO− release, showing both antibacterial and antibiofilm activities. [ABSTRACT FROM AUTHOR]

The title method allows a direct access to one-carbon extended α-aminonitriles via oxidation of amines and subsequent cyanation of the resulting imine intermediate with trimethylsilyl cyanide. [ABSTRACT FROM AUTHOR]

A diverse range of primary or secondary alkyl thioethers is prepared in a scalable manner. [ABSTRACT FROM AUTHOR]

The NHC‐catalyzed 1‐azadiene Diels—Alder reactions give efficient access to optically active benzothiazolopyridinone derivatives. [ABSTRACT FROM AUTHOR]

Palladium im angeregten Zustand katalysiert die stereoselektive decarboxylierende Alkylierung α,β‐ungesättigter Säuren, wie M. Rueping, L. Cavallo et al. in ihrer Zuschrift auf S. 3450 schildern. Die oxidative Addition von Alkylbromid an Pd0 im Grundzustand ist ein Prozess mit hoher Energiebarriere, weshalb die Reaktion ohne Licht nicht ablaufen kann (dunkle Seite im Bild). Pd0 im Triplettzustand, erzeugt durch Bestrahlung mit sichtbarem Licht, kann jedoch leicht mit dem Alkylbromid über einen barrierefreien SET reagieren, was zu einer decarboxylierenden Alkylierung führt (helle Seite im Bild). [ABSTRACT FROM AUTHOR]

An abstract of the article "A Facile and Regioselective Synthesis of 1-Tetralones via Silver-Catalyzed Ring Expansion" by J. Yu, H. Zhao and colleagues is presented.

Starting from tertiary cyclopropanol and cyclobutanol precursors, a variety of β- and γ-fluorinated ketones are efficiently synthesized via silver-catalyzed ring opening reactions. [ABSTRACT FROM AUTHOR]

A wide range of chlorinated and brominated isoxazolines is prepared through Pd-catalyzed cyclization of oxime substrates in the presence of CuCl2 or CuBr2. [ABSTRACT FROM AUTHOR]