Visible-Light-Induced -Quinone Methides Formation in Situ Using -Alkylarenols as Precursors for Tandem [4 + 2] Cycloaddition Reaction.

Reported herein is the generation of -quinone methides (-QMs) via metal-free visible-light-induced oxidation of -alkylarenols, as well as their subsequent reaction with olefins to afford chromans in good to excellent yields (up to 91%). The key is the selective activation of the benzylic C(sp)-H bond of -alkylarenols via single electron transfer (SET) and the formation of -QMs via hydrogen atom transfer (HAT).

Two-Dimensional Conjugated Metal-Organic Frameworks for Photochemical Transformations.

Photochemical transformation represents an attractive pathway for the conversion of earth-abundant resources, such as HO, CO, O, and N, into valuable chemicals by utilizing sunlight as an energy source. Recently, two-dimensional conjugated metal-organic frameworks (2D c-MOFs) have emerged as the focal points in the field of photo-to-chemical conversion due to their advantages in light harvesting, electrical conductivity, mass transport, tunable electronic and porous structures, as well as abundant active sites. In this review, we highlight various physical and chemical features of 2D c-MOFs that can contribute to enhanced photo-induced exciton generation, charge transport, proton migration and redox catalysis.

A Helical Tubular Dyad of [9]Cycloparaphenylene: Synthesis, Chiroptical Properties and Post-Functionalization.

The bottom-up synthesis of discrete tubular molecules that mimic the structural features of carbon nanotubes has been a long-standing pursuit for synthetic chemists. As the shortest segments of armchair-type carbon nanotubes, cycloparaphenylenes are regarded as ideal macrocyclic building blocks for achieving this goal. Here we report the synthesis of a helical tubular molecule featuring three diyne linkers between two site-specifically functionalized [9]cycloparaphenylenes.

Promoting Charge-Carriers Dynamics by Relaxed Lattice Strain in A-site-Doped Halide Perovskite for Photocatalytic H Evolution.

Because of the unique and superior optoelectronic properties, metal halide perovskites (MHPs) have attracted great interest in photocatalysis. Element doping strategy is adopted to modify perovskite materials to improve their photocatalytic performance. However, the contribution of bare doping-site onto photocatalytic efficiency, and the correlation between doping locations and activity have not yet to be demonstrated.

Single Molecular Dispersion of Crown Ether-Decorated Cobalt Phthalocyanine on Carbon Nanotubes for Robust CO Reduction through Host-Guest Interactions.

Immobilizing molecular catalysts on electro-conductive supports (for example, multi-walled carbon nanotubes, CNTs) represent a promising way to well-defined catalyst/support interfaces, which has shown appreciable performance for catalytic transformation. However, their full potential is far from achieved due to insufficient utilization of the intrinsic activity for each immobilized molecular catalyst, especially at loadings that should allow decent current densities. In the present work, we discover host-guest interaction between tetra-crown ether substituted cobalt phthalocyanine and metal ions, for example K ions, not only eliminate catalyst aggregation at immobilization procedures but also reinforce catalyst/support interactions by additional electrostatic attractions under operational conditions.

Spin-related excited-state phenomena in photochemistry.

The spin of electrons plays a vital role in chemical reactions and processes, and the excited state generated by the absorption of photons shows abundant spin-related phenomena. However, the importance of electron spin in photochemistry studies has been rarely mentioned or summarized. In this review, we briefly introduce the concept of spin photochemistry based on the spin multiplicity of the excited state, which leads to the observation of various spin-related photophysical properties and photochemical reactivities.

Photoelectrochemical Ni-catalyzed cross-coupling of aryl bromides with amine at ultra-low potential.

Photoelectrochemical (PEC) cell is an ideal platform for organic transformation because of its green benefits and minimal energy consumption. As an emerging methodology, the reaction types of photoelectrocatalytic organic synthesis (PECOS) are limited to simple oxidation and C-H activation at current stage. Metal catalysis for the construction of C(sp)-N bonds has not been touched yet in PECOS.

Photocatalytic Cross-Coupling of Aldehydes and Alkenes for Aryl Vinyl Ketones by a Single Catalyst.

Herein is the first example of photocatalytic cross-coupling of alkenes with aldehydes by a single catalyst without an external photosensitizer and any additives. Irradiation of the aromatic aldehyde and cobaloxime catalyst results in the formation of an acyl radical, which undergoes radical addition with alkene or indole and subsequently β-H elimination to afford alkenyl ketone. The reaction features cheap and readily available raw materials, a broad substrate scope, and mild conditions, even for late-stage derivatization of bioactive compounds.

1,3-Difunctionalization of Alkenes by Cobaloxime Photocatalysis.

Represented herein is the first 1,3-difunctionalization of alkenes via photocatalysis. A single cobaloxime is used to carry out two catalytic cycles in which cobaloxime is used not only as a photocatalyst to initiate the reaction but also as a metal catalyst for the β-H elimination process. Electron-deficient alkenes, electron-rich alkenes, and unactivated alkenes could be directly converted to 1,3-bisphosphorylated products, even unsymmetric 1,3-bisphosphorylated products, with only H as a byproduct under extremely mild reaction conditions.

A Bibliometric Analysis on Research Progress of Earthworms in Soil Ecosystems.

The earthworm, as a soil engineer, plays highly important roles in the soil ecosystem for shaping soil structure, promoting soil fertility, regulating microbial community composition and activities and decomposing soil pollutants. However, the research progresses on this important soil fauna have rarely been reviewed so far. Therefore, we conducted a bibliometric analysis of the literature published during 1900-2022, which was collected from the Web of Science Core Collection (WoS).

Photocatalytic Cracking of non-Biodegradable Plastics to Chemicals and Fuels.

Plastic pollution is worsening the living conditions on Earth, primarily due to the toxicity and stability of non-biodegradable plastics (NBPs). Photocatalytic cracking of NBPs is emerging as a promising way to cleave inert C-C bonds and abstract the carbon atoms from these wastes into valuable chemicals and fuels. However, controlling these processes is a huge challenge, ascribed to the complicated reactions of various NBPs.

Synthesis of All-Benzene Multi-Macrocyclic Nanocarbons by Post-Functionalization of meta-Cycloparaphenylenes.

Expanding the diversity of multi-macrocyclic nanocarbons, particularly those with all-benzene scaffolds, represents intriguing yet challenging synthetic tasks. Complementary to the existing synthetic approaches, here we report an efficient and modular post-functionalization strategy that employs iridium-catalyzed C-H borylation of the highly strained meta-cycloparaphenylenes (mCPPs) and an mCPP-derived catenane. Based on the functionalized macrocyclic synthons, a number of novel all-benzene topological structures including linear and cyclic chains, polycatenane, and pretzelane have been successfully prepared and characterized, thereby showcasing the synthetic utility and potential of the post-functionalization strategy.

Engineering Ultrathin CuS Layer on Planar SbS Photocathode to Enhance Photoelectrochemical Transformation.

SbS has been extensively used as light absorber for photoelectrochemical cell. However, its p-type nature may result in the formation of Schottky junction with substrates, thus hindering the collection of photogenerated holes. Herein, an ultrathin CuS layer is successfully engineered as the bottom junction for SbS for the first time.

Photocatalytic Generation of Carbocation from Thiols and Application to Cross-Nucleophile Coupling.

Represented herein is a simple thiol identified as an effective precursor to photochemically form a carbocation. Thanks to the thiyl radical rapid transformation to disulfide, which serves not only to stabilize the generated thiyl radical but also to allow the second electron transfer to form a carbocation. The resulting carbocations, including primary benzylic, secondary, and tertiary carbocations, can smoothly couple with nitrogen, oxygen, and carbon nucleophilic coupling partners as well as complex drug molecules, accompanied by elemental sulfur formation in air.

Interfacial Charge Transfer Regulates Photoredox Catalysis.

Photoredox catalytic processes offer the potential for precise chemical reactions using light and materials. The central determinant is identified as interfacial charge transfer, which simultaneously engenders distinctive behavior in the overall reaction. An in-depth elucidation of the main mechanism and highlighting of the complexity of interfacial charge transfer can occur through both diffusive and direct transfer models, revealing its potential for sophisticated design in complex transformations.

Photothermal Mineralization of Polyolefin Microplastics via TiO Hierarchical Porous Layer-Based Semiwetting Air-Plastic-Solid Interfaces.

Photo-mineralization of microplastics under mild conditions has emerged as a promising solution to plastic waste disposal. However, the inadequate contact between oxygen, water-insoluble polyolefin microplastics, and photocatalysts remains a critical issue. In this study, a TiO hierarchical porous layer (TiO-HPL) photocatalyst is presented to establish air-plastic-solid triphase interfaces for the photothermal mineralization of polyolefins.

Concurrent Ammonia Synthesis and Alcohol Oxidation Boosted by Glutathione-Capped Quantum Dots under Visible Light.

Mother nature accomplishes efficient ammonia synthesis via cascade N oxidation by lightning strikes followed with enzyme-catalyzed nitrogen oxyanion (NO , x = 2,3) reduction. The protein environment of enzymatic centers for NO -to-NH process greatly inspires the design of glutathione-capped (GSH) quantum dots (QDs) for ammonia synthesis under visible light (440 nm) in tandem with plasma-enabled N oxidation. Mechanistic studies reveal that GSH induces positive shift of surface charge to strengthen the interaction between NO and QDs.

Structural and Compositional Changes in Two Marine Shell Traditional Chinese Medicines: A Comparative Analysis Pre- and Post-Calcination.

Background: Arcae concha and Meretricis concha cyclinae concha are two marine shellfish herbs with similar composition and efficacy, which are usually calcined and used clinically.

Objective: This study investigated variations in the inorganic and organic components of Arcae concha and Meretricis concha cyclinae concha from different production regions, both Arcae concha and Meretricis concha cyclinae concha. The aim was to enhance the understanding of these two types of marine shell traditional Chinese medicine (msTCM) and provide a foundation for their future development and application.

A Conjugated Phenylene Nanocage with a Guest-Adaptive Deformable Cavity.

The highly strained, phenylene-derived organic cages are typically regarded as very rigid entities, yet their deformation potential and supramolecular properties remain underexplored. Herein, we report a pliable conjugated phenylene nanocage by synergistically merging rigid and flexible building blocks. The anisotropic cage molecule contains branched phenylene chains capped by a calix[6]arene moiety, the delicate conformational changes of which endow the cage with a remarkably deformable cavity.

Modular Synthesis of Improbable Rotaxanes with All-Benzene Scaffolds.

"Improbable" rotaxanes consisting of interlocked conjugated components represent non-trivial synthetic targets, not to mention those with all-benzene scaffolds. Herein, a modular synthetic strategy has been established using an isolable azo-linked pre-rotaxane as the core module, in which the azo group functions as a tracelessly removable template to direct mechanical bond formations. Through versatile connections of the pre-rotaxane and other customizable modules, [2]- and [3]rotaxanes derived from all-benzene scaffolds have been accomplished, demonstrating the utility and potential of the synthetic design for all-benzene interlocked supramolecules.

Surficial Host-Guest Responsive CsPbBr Perovskite Nanocrystals for Programmable Multi-Level Information Encryption.

The design of smart stimuli-responsive photoluminescent materials capable of multi-level encryption and complex information storage is highly sought after in the current information era. Here, a novel adamantyl-capped CsPbBr (AD-CsPbBr) perovskite NCs, along with its supramolecular host-guest assembly partner a modified β-CD (mCD), mCD@AD-CsPbBr, are designed and prepared. By dispersing these two materials in different solvents, namely, AD-CsPbBr in toluene, mCD@AD-CsPbBr in toluene, and mCD@AD-CsPbBr in methanol, the three solutions exhibit diverse photoluminescence (PL) turn-on/off or PL discoloration response upon supramolecular stimulus.

Thiyl Radical Trapped by Cobalt Catalysis: An Approach to Markovnikov Thiol-Ene Reaction.

In the presence of a thiyl radical species, the catalytic Markovnikov thiol-ene reaction is challenging because it prefers to proceed via a radical pathway, thereby leading to -Markovnikov selectivity. In this work, a rare example of thiyl radical engaged in Markovnikov thiol-ene reaction enabled by cobalt catalysis is reported. This protocol features the avoidance of unique oxidants, exclusive regioselectivity, and broad substrate scope.

Regioselective Dearomative Amidoximation of Nonactivated Arenes Enabled by Photohomolytic Cleavage of N-nitrosamides.

Dearomative spirocyclization reactions represent a promising means to convert arenes into three-dimensional architectures; however, controlling the regioselectivity of radical dearomatization with nonactivated arenes to afford the spirocyclizative 1,2-difunctionalization other than its kinetically preferred 1,4-difunctionalization is exceptionally challenging. Here we disclose a novel strategy for dearomative 1,2- or 1,4-amidoximation of (hetero)arenes enabled by direct visible-light-induced homolysis of N-NO bonds of nitrosamides, giving rise to various highly regioselective amidoximated spirocycles that previously have been inaccessible or required elaborate synthetic efforts. The mechanism and origins of the observed regioselectivities were investigated by control experiments and density functional theory calculations.