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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]