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Abstract: Herein, we report a novel strategy for the activation of DMSO to act as a versatile alkylating agent in heteroarene C−H functionalization. This direct, simple, and mild switch between methylation/trideuteromethylation and methylthiomethylation of heteroarenes was achieved under reagent‐controlled photoredox catalysis conditions. The proposed mechanism is supported by both experimental and computational studies. [ABSTRACT FROM AUTHOR]

The oxidative coupling of photogenerated alkyl radicals with readily available styrenes is disclosed. This visible-light-mediated method allows rapid access to a wide range of α-alkyl-acetophenones in good yields and with high functional group tolerance. In addition, the developed protocol features room temperature conditions, low photocatalyst loadings, and the use of dimethyl sulfoxide as nontoxic and mild terminal oxidant. [ABSTRACT FROM AUTHOR]

The development of new hydrogen-atom transfer (HAT) strategies within the framework of photoredox catalysis is highly appealing for its power to activate a desired C−H bond in the substrate leading to its selective functionalization. Reported here is the first photoredox-mediated hydrogen-atom transfer method for the efficient synthesis of ynones, ynamides, and ynoates with high regio- and chemoselectivity by direct functionalization of C [ABSTRACT FROM AUTHOR]

Die Entwicklung neuer Wasserstoffatomtransfer(HAT) ‐ Strategien im Kontext der Photoredoxkatalyse stellt eine hochattraktive Möglichkeit zur gezielten Aktivierung einer C ‐ H ‐ Bindung eines Substrats mit anschließender selektiver Funktionalisierung dar. Wir beschreiben hier das erste Photoredox ‐ vermittelte Wasserstoffatomtransfer ‐ Protokoll zur hoch regio ‐ und chemoselektiven Synthese von Inonen, Inamiden und Inestern, erreicht durch direkte Funktionalisierung von Csp2 (O) ‐ H ‐ Bindungen. Die weitreichenden Anwendungsmöglichkeiten dieser Methode wurden im Rahmen der selektiven Funktionalisierung von C(O) ‐ H ‐ Bindungen in hochkomplexen Molekülgerüsten verdeutlicht. HAT was: Ein Photoredox ‐ katalysierter Wasserstoffatomtransfer zur Erzeugung von Carbonylradikalen ausgehend von Aldehyden und analogen Substraten mit XC(O) ‐ H ‐ Funktionalitäten (X=N, O) wurde entwickelt. Die Funktionalisierung der Carbonylradikale mit Ethinylbenziodoxolon(EBX) ‐ Reagenzien führte zur Synthese komplexer Inone, Inamide und Inester ausgehend von leicht verfügbaren Startmaterialien. [ABSTRACT FROM AUTHOR]

Herein, we disclose a strategy for the activation of N-(acyloxy)phthalimides towards photoinduced electron transfer through hydrogen bonding. This activation mode enables efficient access to C(sp3)-centered radicals upon decarboxylation from bench-stable and readily available substrates. Moreover, we demonstrate that the formed alkyl radicals can be successfully employed in a novel redox-neutral method for constructing sp3−sp3 bonds across styrene moieties that gives straightforward access to complex alcohol and ether scaffolds. [ABSTRACT FROM AUTHOR]

Eine Strategie zur Aktivierung von N‐(Acyloxy)phthalimiden für den photoinduzierten Elektronentransfer durch die Bildung von Wasserstoffbrücken wird vorgestellt. Dieser Aktivierungsmodus führt effektiv zu C(sp3)‐zentrierten Radikalen nach Decarboxylierung von stabilen und leicht zugänglichen Substraten. Darüber hinaus wurde gezeigt, dass die gebildeten Alkylradikale in einem neuartigen redoxneutralen Protokoll zur Bildung von C(sp3)‐C(sp3)‐Bindungen zwischen Styrol‐Einheiten eingesetzt werden können, was einen einfachen Zugang zu komplexen Alkohol‐ und Ethergerüsten ermöglicht. Aktivierendes OH‐Erlebnis: Eine effektive Strategie zur Aktivierung von N‐(Acyloxy)phthalimiden für den direkten photoinduzierten Elektronentransfer mit einem angeregten Photokatalysator wurde entwickelt. Dabei werden Alkylradikale gebildet, die zur milden und redoxneutralen Oxyalkylierung von Styrolen genutzt werden können. [ABSTRACT FROM AUTHOR]

Highly selective tandem nucleophilic addition/cross-coupling reactions of alkynes have been developed using visible-light-promoted dual gold/photoredox catalysis. The simultaneous oxidation of AuI and coordination of the coupling partner by photo-generated aryl radicals, and the use of catalytically inactive gold precatalysts allows for high levels of selectivity for the cross-coupled products without competing hydrofunctionalization or homocoupling. As demonstrated in representative arylative Meyer-Schuster and hydration reactions, this work expands the scope of dual gold/photoredox catalysis to the largest class of substrates for gold catalysts and benefits from the mild and environmentally attractive nature of visible-light activation. [ABSTRACT FROM AUTHOR]

Herein, we report a new visible-light-promoted strategy to access radical trifluoromethylthiolation reactions by combining halide and photoredox catalysis. This approach allows for the synthesis of vinyl-SCF3 compounds of relevance in pharmaceutical chemistry directly from alkenes under mild conditions with irradiation from household light sources. Furthermore, alkyl-SCF3-containing cyclic ketone and oxindole derivatives can be accessed by radical-polar crossover semi-pinacol and cyclization processes. Inexpensive halide salts play a crucial role in activating the trifluoromethylthiolating reagent towards photoredox catalysis and aid the formation of the SCF3 radical. [ABSTRACT FROM AUTHOR]

Symmetrical diarylalkenes such as (I), the unsymmetrical analogue (IVc) and a series of styrenes are subjected to conditions A) to produce pharmaceutically important vinyl-S-CF3 compounds. [ABSTRACT FROM AUTHOR]

Highly selective tandem nucleophilic addition/cross-coupling reactions of alkynes have been developed using visible-light-promoted dual gold/photoredox catalysis. The simultaneous oxidation of Au(I) and coordination of the coupling partner by photo-generated aryl radicals, and the use of catalytically inactive gold precatalysts allows for high levels of selectivity for the cross-coupled products without competing hydrofunctionalization or homocoupling. As demonstrated in representative arylative Meyer-Schuster and hydration reactions, this work expands the scope of dual gold/photoredox catalysis to the largest class of substrates for gold catalysts and benefits from the mild and environmentally attractive nature of visible-light activation., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)