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This work showcases a novel visible‐light mediated allenylation protocol employing propargyl sulfides as a pioneering radical trapping methodology. A diverse array of substituted sulfonyl allenes were successfully synthesized under mild conditions with commendable levels of chemo‐ and regio‐selectivity. Mechanistically, this process entails the formation of sulfonyl radicals, their subsequent addition to alkynes, the subsequent elimination of S‐centered radicals, and Cl‐atom abstraction, thereby facilitating the propagation of this radical chain reaction. [ABSTRACT FROM AUTHOR]

This article discusses the synthesis and characterization of various 1-thiaphenalene derivatives using a radical approach and photoredox catalysis. The reaction involves the intermolecular cyclization of 1-naphthalenesulfonyl chlorides and alkynes under mild conditions, resulting in high product diversity and broad functional-group tolerance. The authors provide a plausible reaction mechanism and experimental details for the synthesis of specific compounds, which were characterized using techniques such as NMR, HRMS, and IR spectroscopy. This information can be valuable for researchers studying these compounds or related topics. [Extracted from the article]

The solar‐driven evolution of hydrogen from water using particulate photocatalysts is considered one of the most economical and promising protocols for achieving a stable supply of renewable energy. However, the efficiency of photocatalytic water splitting is far from satisfactory due to the sluggish electron‐hole pair separation kinetics. Herein, isolated Mo atoms in a high oxidation state have been incorporated into the lattice of Cd0.5Zn0.5S (CZS@Mo) nanorods, which exhibit photocatalytic hydrogen evolution rate of 11.32 mmol g−1 h−1 (226.4 μmol h−1; catalyst dosage 20 mg). Experimental and theoretical simulation results imply that the highly oxidized Mo species lead to mobile‐charge imbalances in CZS and induce the directional photogenerated electrons transfer, resulting in effectively inhibited electron‐hole recombination and greatly enhanced photocatalytic efficiency. [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]

As a renewable aromatic compound with enormous production potential, lignin has various potential high-value utilization pathways, but the success achieved in the field of photocatalysis is limited. Herein, this work prepares a new type of photocatalyst by modifying Graphitic Carbon Nitride Nanotubes (CNT) with self-assembled lignin nanospheres for the photocatalytic production of H 2 O 2 and the degradation of azo dyes. Under light conditions, lignin enhances the production of H 2 O 2 through oxygen reduction and collaborates with carbon nitride tubes to generate O 2 − and 1O 2. Furthermore, carbon nitride tubes form electron-rich regions with lignin, promoting the transfer of electrons from adsorbed aromatic pollutants to this region, thereby facilitating their degradation. The experimental results indicate that the addition of 5 % lignin significantly enhances the photocatalytic degradation efficiency of azo dyes, with a degradation rate 1.87 times higher than that of the original carbon nitride tubes. Furthermore, CNL also have excellent degradation ability to pollutants in actual wastewater. This study provides new insights and prospects for the high-value utilization of lignin, enabling it to be used as a photocatalytic co-catalyst to participate in the photocatalytic degradation of environmental pollutants. • Photocatalyst CNL5 was synthesized by modifying carbon nitride with lignin, improving its photocatalytic activity. • Study on the mechanism of lignin-modified carbon nitride nanotubes photocatalytic production of H 2 O 2. • By π-π attraction, the electrons of pollutants participate in the photocatalytic reaction. • The application and challenges of high value utilization of lignin in photocatalysis. [ABSTRACT FROM AUTHOR]

Trisubstituted alkenes are important organic synthons and have broad applications in the synthesis of many pharmaceuticals and materials. The stereoselective synthesis of such compounds has long been a research focus for organic researchers. Herein, we report a three-component, reductive cascade, cross-coupling reaction for the arylalkylation of alkynes. A wide range of trisubstituted alkenes are obtained in good to high yields with excellent chemo- and stereoselectivity by switching between electrochemistry and photocatalysis. The E isomer of the product is obtained exclusively when the reaction is conducted with electricity and nickel, while the Z isomer is generated with high stereoselectivity when photo- and nickel dual catalysts are used. Moreover, photo-assisted electrochemically enabled nickel catalyzed protocol is demonstrated to selectively deliver Z-trisubstituted alkenes without the addition of photocatalysts. The construction of trisubstituted alkenes with high stereoselectivity is challenging. Here, the authors realize the stereodivergent synthesis of such compounds via switching between electrochemistry, photochemistry and photoelectrochemistry. [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]

Regioselective incorporation of a particular functional group into aliphatic sites by direct activation of unreactive C−H bonds is of great synthetic value. Despite advances in radical‐mediated functionalization of C(sp3)−H bonds by a hydrogen‐atom transfer process, the site‐selective vinylation of remote C(sp3)−H bonds still remains underexplored. Reported herein is a new protocol for the regioselective vinylation of unactivated C(sp3)−H bonds. The remote C(sp3)−H activation is promoted by a C‐centered radical instead of the commonly used N and O radicals. The reaction possesses high product diversity and synthetic efficiency, furnishing a plethora of synthetically valuable E alkenes bearing tri‐/di‐/mono‐fluoromethyl and perfluoroalkyl groups. Give and take: Regioselective incorporation of a particular functional group into aliphatic sites by direct activation of unreactive C−H bonds remains challenging. Herein a new protocol for the regioselective vinylation of unactivated C(sp3)−H bonds is reported. The activation of a remote C(sp3)−H bond is promoted by a C‐centered radical instead of the commonly used N and O radicals. [ABSTRACT FROM AUTHOR]

Abstract: A general and practical protocol for elusive carbo‐difluoroalkylation/ monofluoroalkylation of unactivated alkenes based on the distal functional group migration is described. A portfolio of functional groups including heteroaryl, imino, formyl, and alkynyl groups showcase the migratory aptitude. In combination with visible‐light photocatalysis, a broad range of di‐ and mono‐fluorinated alkyl ketones are readily obtained in synthetically useful yields under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Abstract: Reported for the first time is a tertiary‐alcohol‐guided heteroarylation of remote C(sp3)−H bonds. The mild and direct generation of alkoxyl radicals from alcohols is enabled by visible‐light photocatalysis. A remote hydrogen atom and heteroaryl migration sequence are involved in the reaction. Many sensitive groups remain intact in the reaction, thus illustrating wide functional‐group compatibility. This protocol provides a practical strategy for the late‐stage modification of alkyl ketones. [ABSTRACT FROM AUTHOR]

A general protocol for the challenging cyanofluoroalkylation of unactivated alkenes is disclosed. A broad range of synthetically useful di- and mono-fluorinated alkyl nitriles are readily obtained in good yields under mild reaction conditions. The efficient combination of intramolecular cyano migration and photoredox catalysis significantly expands the field of difunctionalization of olefins. [ABSTRACT FROM AUTHOR]

Disclosed herein is a novel, redox-neutral protocol for the visible-light-induced radical alkynylation of unactivated olefins. The intramolecular migration of an alkynyl group, by cleaving an inert C−C σ bond, is realized for the first time. A wide range of synthetically useful trifluoroethylated linear alkynes are readily obtained under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Chen Zhu: (left) received his B.S. degree from Xiamen University in 2003 under the supervision of Prof. Pei-Qiang Huang, and his Ph.D. degree from the Shanghai Institute of Organic Chemistry in 2008 under the supervision of Prof. Guo-Qiang Lin. After postdoctoral research at -Gakushuin University, Japan with Prof. Takahiko Akiyama, he moved to the University of Texas Southwestern Medical Center, working as a postdoctoral fellow with Prof. John R. Falck and Prof. Chuo Chen. He was appointed as a professor at Soochow University, China in December 2013. He is currently the Head of the Organic Chemistry Department at Soochow University. His current research interests include radical-mediated transformations, in particular radical -rearrangements, and their applications in the construction of natural products and biologically active compounds. Xin-Yuan Liu (right) obtained his B.S. degree from Anhui Normal University (AHNU) in 2001. He continued his research studies at both the Shanghai Institute of Organic Chemistry (SIOC), CAS and AHNU under the joint supervision of Prof. Dr. Shizheng Zhu and Prof. Dr. Shaowu Wang, obtaining his master's degree in 2004. After a one-year stint in Prof. Gang Zhao's laboratory at SIOC, he joined Prof. Dr. Chi-Ming Che's group at The University of Hong Kong (HKU) and earned his Ph.D. degree in 2010. He subsequently undertook postdoctoral studies in Prof. Che's group at HKU and in Prof. Carlos F. Barbas III's group at The Scripps Research Institute. At the end of 2012, he began his independent academic career at the Southern University of Science and Technology (SUSTech) and was promoted to a tenured Full Professor of SUSTech in 2018. His research interests are directed towards the design of novel chiral anionic ligands to solve radical-involved asymmetric reactions. [ABSTRACT FROM AUTHOR]