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Summary of main observation and conclusion An enantioselective deoxygenative cyanation of benzyl alcohols was accomplished for the first time through the synergistic photoredox and copper catalysis. This reaction features the use of organic photosensitizer and low‐cost 3d metal catalyst, simple and safe operations, and extremely mild conditions. A variety of chiral benzyl nitriles were produced in generally good yields and high level of enantiocontrols from readily available feedstocks (22 examples, up to 93% yield and 92% ee). [ABSTRACT FROM AUTHOR]

Alkene bifunctionalizations are powerful tools for the rapid construction of structurally complex and valuable scaffolds, and such reactions typically involve the use of transition‐metal catalysts or organocatalysts. Here, we report for the first time a photogenerated neutral nitrogen radical catalyzed intermolecular alkene bifunctionalization by using allyl sulfones as the source of both the carbon and the sulfone functionalities under mild conditions. The key to the success of this protocol involves the visible‐light‐mediated photocatalytic in situ generation of a nitrogen‐centered radical from the N‐(2‐acetylphenyl) benzenesulfonamide catalyst, and its activation of the allyl sulfones to generate reactive species. The preliminary control experiments supported the postulated mechanism. [ABSTRACT FROM AUTHOR]

The palladium‐catalyzed Heck reaction is a well‐known, Nobel Prize winning transformation for producing alkenes. Unlike the alkenyl and aryl variants of the Heck reaction, the alkyl‐Heck reaction is still underdeveloped owing to the competitive side reactions of alkyl–palladium species. Herein, we describe the development of a deaminative alkyl‐Heck‐type reaction that proceeds through C−N bond activation by visible‐light photoredox catalysis. A variety of aliphatic primary amines were found to be efficient starting materials for this new process, affording the corresponding alkene products in good yields under mild reaction conditions. Moreover, this strategy was successfully applied to deaminative carbonylative alkyl‐Heck‐type reactions. Single‐electron process: A deaminative alkyl‐Heck‐type reaction and its carbonylative variant proceed through photocatalytic C−N bond activation. This process represents a significant complement to the classic palladium‐catalyzed Heck reaction, and features easily available starting materials, good reaction efficiency, and mild reaction conditions. Tppy=2,4,6‐triphenylpyridine. [ABSTRACT FROM AUTHOR]

Visible‐light photocatalysis is a rapidly developing and powerful strategy to initiate organic transformations, as it closely adheres to the tenants of green and sustainable chemistry. Generally, most visible‐light‐induced photochemical reactions occur through single‐electron transfer (SET) pathways. Recently, visible‐light‐induced energy‐transfer (EnT) reactions have received considerable attentions from the synthetic community as this strategy provides a distinct reaction pathway, and remarkable achievements have been made in this field. In this Review, we highlight the most recent advances in visible‐light‐induced EnT reactions. Making light of synthesis: The distinctive reaction pathways provided by visible‐light‐induced energy transfer (EnT) has resulted in it receiving considerable attention. This Review discusses the most recent advances in visible‐light‐induced EnT reactions. [ABSTRACT FROM AUTHOR]

Two visible-light driven alkenylation reactions of unactivated alkyl bromides, which were enabled by the use of Ir(dF(CF3)ppy)2(dtbbpy)PF6 as the photocatalyst and (TMS)3SiH as the atom transfer reagent to activate the alkyl bromides, were described for the first time. These protocols can be used to produce a variety of alkenes from easily available feedstock with good reaction efficiency and high chemoselectivity under mild reaction conditions. To further demonstrate the applicability of the present strategy, the alkenylation of bioactive molecules and glycosyl bromides, as well as the alkynylation of unactivated alkyl bromides, was proven to be feasible. [ABSTRACT FROM AUTHOR]

A photoredox-catalyzed iminyl radical-triggered C–C bond cleavage/addition/Kornblum oxidation cascade of cycloketone oxime esters and styrenes in DMSO is described. This three-component, one-pot procedure features mild conditions, a broad substrate scope, and high functional group tolerance, providing an efficient approach to access diversely functionalized ketonitriles. [ABSTRACT FROM AUTHOR]

On the basis of the strategy of iminyl radical-mediated C–C bond cleavage, a visible light photocatalytic radical addition/cyclization cascade is described, providing an efficient and regioselective access to cyanoalkylated 1,2,3,4-tetrahydrophenanthrenes. [ABSTRACT FROM AUTHOR]

Abstract: A visible light‐induced photocatalytic radical addition/cyclization reaction of o‐vinyl‐N‐alkoxybenzamides has been accomplished for efficient synthesis of diversely functionalized CF3‐containing iminoisobenzofurans. This external oxidant‐free and mild protocol features ready availability of starting materials, excellent regioselectivity, good substrate scope and functional group tolerance. [ABSTRACT FROM AUTHOR]

An efficient visible light photocatalytic and external oxidant-free N-radical 5-exo cyclization/addition/aromatization cascade of β,γ-unsaturated hydrazones is described, which provides a practical route to various biologically interesting dihydropyrazole-fused benzosultams in satisfactory yields. [ABSTRACT FROM AUTHOR]

A cooperative TEMPO and photoredox catalytic strategy was applied for the first time to the direct conversion of N−H and O−H bonds into N- and O-centred radicals, enabling a general and selective oxidative radical oxyamination and dioxygenation of various β,γ-unsaturated hydrazones and oximes. In the reaction, O2 was employed not only as a terminal oxidant but also as the oxygen source. This protocol provided efficient access to the synthesis of various synthetically and biologically important pyrazoline, pyridazine and isoxazoline derivatives under metal-free and mild reaction conditions. Mechanistic studies revealed that the cooperative organophotocatalytic system functions through two single-electron-transfer (SET) processes. [ABSTRACT FROM AUTHOR]

The efficient visible light photocatalytic azotrifluoromethylation of alkenes with aryldiazonium salts and sodium triflinate is described, which gave the corresponding trifluoromethylated azo compounds in generally good yields. The trifluoromethylated azo products can be easily transformed into useful heterocycles and nitrogen-containing building blocks. [ABSTRACT FROM AUTHOR]

Bicarbonyl-substituted sulfur ylide is a useful, but inert reagent in organic synthesis. Usually, harsh reaction conditions are required for its transformation. For the first time, it was demonstrated that a new, visible-light photoredox catalytic annulation of sulfur ylides under extremely mild conditions, permits the synthesis of oxindole derivatives in high selectivities and efficiencies. The key to its success is the photocatalytic single-electron-transfer (SET) oxidation of the inert amide and acyl-stabilized sulfur ylides to reactive radical cations, which easily proceeds with intramolecular C−H functionalization to give the final products. [ABSTRACT FROM AUTHOR]

Radicals are an important class of versatile and highly reactive species. Compared with the wide applications of various C-centred radicals, however, the N-radical species including N-centred radicals and radical ions remain largely unexplored due to the lack of convenient methods for their generation. In recent years, visible light photoredox catalysis has emerged as a powerful platform for the generation of various N-radical species and methodology development towards the synthesis of diverse N-containing compounds. In this tutorial review, we highlight recent advances in this rapidly developing area with particular emphases put on the working models and new reaction design. [ABSTRACT FROM AUTHOR]

Photocatalysis enables the cascade reactions of indoles and CBr4 in MeOH through a C(sp2)H functionalization/methanolysis sequence. The title reaction provides an efficient access to indole 2- and 3-carboxylates in a single operation (no preinstallation of protecting as well as directing groups was required) with good yields under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Visible-light-induced photocatalytic decarboxylative alkynylations of carboxylic acids have been developed for the first time. The reaction features extremely mild conditions, broad substrate scope, and avoids additional oxidants. Importantly, a decarboxylative carbonylative alkynylation has also been carried out in the presence of carbon monoxide (CO) under photocatalytic conditions, which affords valuable ynones in high yields at room temperature. [ABSTRACT FROM AUTHOR]

A visible-light-induced photocatalytic oxytrifluoromethylation reaction of N-allylamides has been developed for the efficient synthesis of CF3-containing oxazolines and benzoxazines under mild reaction conditions. [ABSTRACT FROM AUTHOR]

The first radical alkoxycarboxylation of aryldiazonium salts using CO gas through visible-light-induced photoredox catalysis (16 W blue LEDs) has been developed. This reaction is entirely metal-free, is carried out at room temperature with a low loading of an organic dye as a photocatalyst (0.5 mol %), and provides a wide range of arylcarboxylic acid esters in high yields. Importantly, this photocatalytic system can be successfully extended to other carboxylation reactions. [ABSTRACT FROM AUTHOR]

An unprecedented phototandem catalysis based on a single iridium photocatalyst has been successfully developed. This powerful strategy consists of two mechanistically distinct catalytic cycles, namely, photocatalytic energy transfer (ET) and single electron transfer (SET). The novel protocol allows a rapid and efficient construction of biologically and synthetically important 3-ester-3- hydroxy-2-oxindole derivatives from readily available diazoamides through a cyclization/aerobic oxidation sequence under very mild conditions. [ABSTRACT FROM AUTHOR]

A visible-light photocatalytic generation of N-centered hydrazonyl radicals has been accomplished for the first time. This approach allows efficient intramolecular addition of hydrazonyl radical to terminal alkenes, thus providing hydroamination and oxyamination products in good yields. Importantly, the protocol involves deprotonation of an NH bond and photocatalytic oxidation to an N-centered radical, thus obviating the need to prepare photolabile amine precursors or the stoichiometric use of oxidizing reagents. [ABSTRACT FROM AUTHOR]

The article focuses on several development of mild processes that enable the controlled activation and functionalization of remote C-H bonds in hydrocarbons. Topics discussed include radical translocation processes mediated by heteroatom radicals providing a potential platform for the controlled functionalization of remote inert C-H bond; currently used methods usually require high-energy ultra violet (UV) irradiation; and use of visible-light photoredox catalysis for C-H functionalization.

A visible light photocatalytic arylation-lactonization sequence has been developed for the synthesis of γ,γ-disubstituted butyrolactones. This unprecedented transformation features simple experimental procedures under very mild conditions. A one-step synthesis of isobenzofuran-1(3 H)-one has been carried out to demonstrate the synthetic application of this reaction. [ABSTRACT FROM AUTHOR]

Carbocyclic and heterocyclic ring systems are important structural architectures in many bioactive natural products, as well as in a variety of fine chemicals. The utilization of visible-light photocatalytic strategies to construct these ring systems has received considerable attention in the past few years. This microreview presents a brief summary of the use of visible-light photoredox catalytic strategies for the synthesis of carbocyclic and heterocyclic targets. [ABSTRACT FROM AUTHOR]

In the last few years, visible-light initiated organic transformations have attracted increasing attention. The development of visible-light-promoted photocatalytic reactions, which enable rapid and efficient synthesis of fine chemicals, is highly desirable from the viewpoint of cost, safety, availability, and environmental friendliness. In this Minireview, recent advances made in this fast developing area of research are discussed. [ABSTRACT FROM AUTHOR]

Visible ‐ Light Photocatalysis The photocatalytic activation of the inert amide and acyl ‐ stabilized sulfur ylides are accomplished for the first time. Usually, the activation of this kind of sulfur ylides occurs under harsh reaction conditions. This visible ‐ light ‐ driven photoredox protocol can realize the construction of oxindole derivatives under extremely mild conditions. The key to its success is the photocatalytic single ‐ electron ‐ transfer (SET) oxidation of the inert sulfur ylides to reactive radical cations, which easily proceeds with intramolecular C−H functionalization to give the final products. For more details, see the Communication by L. ‐ Z Wu, W. ‐ J. Xiao et al. on page 8432 ff. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion An enantioselective deoxygenative cyanation of benzyl alcohols was accomplished for the first time through the synergistic photoredox and copper catalysis. This reaction features the use of organic photosensitizer and low‐cost 3d metal catalyst, simple and safe operations, and extremely mild conditions. A variety of chiral benzyl nitriles were produced in generally good yields and high level of enantiocontrols from readily available feedstocks (22 examples, up to 93% yield and 92% ee). [ABSTRACT FROM AUTHOR]

The relationship between oxygen vacancy (OV) concentration of semiconductors and their photocatalytic performances is far from clarified. In this study, by tuning the OV concentration of BiOCl (001) surface via a novel H 2 O 2 treatment coupled infrared irradiation method, we demonstrate that OV concentration of BiOCl (001) surface strongly determine its surface atomic and electronic structures to modulate the photocatalytic pathways. Being of shorter Bi Bi and Bi O bond lengths as well as more electrons being less localized, BiOCl (001) surface with higher OV concentration favored molecular oxygen activation to generate O 2 2− via a two-electron transfer pathway, while the generated O 2 2− could prevent the over oxidation of amines and thus achieve high selectivity in the oxidation of amines to imines. Similar phenomena were also observed for other semiconductor photocatalysts such as TiO 2 and Nb 2 O 5 , suggesting the generality of oxygen vacancy concentration mediated selectivity enhancement. These findings shed light on the relationship between the oxygen vacancy concentration and the surface structure of semiconductor photocatalysts and offer a novel pathway to realize photocatalytic selective oxidation of amines to imines. [ABSTRACT FROM AUTHOR]

A photoredox-mediated carboxylation of heterocycles and even electron-rich benzenes is described. [ABSTRACT FROM AUTHOR]