Enhancing Stability and Activity of Fe-based Catalysts for Propane Dehydrogenation via Anchoring Isolated Fe-Cl Sites.

The eco-friendly features and desirable catalytic activities of Fe-based catalysts make them highly promising for propane dehydrogenation (PDH). However, simultaneously improving their stability and activity remains a challenge. Here, we present a strategy to address these issues synergistically by anchoring single-atom Fe-Cl sites in Al3+ vacancies of Al2O3.

A novel efficient liquefaction process for corn starch through ternary deep eutectic solvent: Products characterization and liquefaction mechanism.

A novel approach for the solvothermal liquefaction of corn starch (CS) was investigated, using ternary deep eutectic solvent (TDES) as both an acidic catalyst and a source of liquefaction reagent. Synergistic effects from multi-component TDES were observed, leading to milder reaction conditions (110 °C, 35 min) and improved product selectivity (relative content of polyhydroxy compounds up to 97.83 %).

Addition of SHR-1701 to first-line capecitabine and oxaliplatin (XELOX) plus bevacizumab for unresectable metastatic colorectal cancer.

This phase 2/3 trial (NCT04856787) assessed the efficacy and safety of SHR-1701, a bifunctional protein targeting PD-L1 and TGF-β, in combination with BP102 (a bevacizumab biosimilar) and XELOX (capecitabine plus oxaliplatin) as a first-line treatment for unresectable metastatic colorectal cancer (mCRC). In this phase 2 study, a total of 62 patients with untreated, histologically confirmed colorectal adenocarcinoma and no prior systemic therapy for metastatic disease were enrolled. Patients received SHR-1701 (30 mg/kg), bevacizumab (7.

CeCl-Catalyzed C-H Alkylation of -Sulfonyl Ketimines with Alkanes and Ether via Photoinduced Ligand-to-Metal Charge Transfer.

A cerium-catalyzed C-H alkylation of -sulfonyl ketimines with low-cost and readily available alkanes as alkyl sources was developed. This transformation proceeded through the synergy of photoinitiated ligand-to-metal charge transfer (LMCT) using a chlorine radical as an HAT reagent and air as a green oxidant. A series of alkylated -sulfonyl ketimines were synthesized with moderate to good yields in a highly atom-economic manner under chemical oxidant-free conditions.

Photochemical upcycling of polymers visible light-driven C-H bond activation.

The excessive use and improper disposal of plastics have placed a significant burden on the environment. To mitigate this impact, prioritizing the chemical upcycling of plastics is crucial. Unlike traditional thermochemical upcycling, which requires harsh conditions such as high temperatures and pressures, photochemical upcycling is viewed as a more environmentally friendly and cost-effective alternative.

Extraction mechanism of phenolic compounds by a choline chloride/glycerol solvent: DFT and molecular dynamics studies.

The mechanism of a solvent consisting of choline chloride and glycerol (ChCl/GLY) for extracting phenolic compounds from coal tar was theoretically studied using density functional theory calculations and molecular dynamics simulations. The thermodynamic properties, interaction essence, and molecular dynamics properties of the extraction system were investigated, as well as the influence of ChCl/GLY on the vibration spectra of phenolic compounds. The results show that the solvation free energy of phenolic compounds in ChCl/GLY is more negative than that in coal tar, leading to the spontaneous transfer of phenolic compounds from coal tar to ChCl/GLY.

N-Directed, Radical Relay Enantioconvergent Sulfinylation of Distal C(sp)-H Bonds via Cobalt Catalysis.

Cobalt-catalyzed enantioconvergent cross-coupling of C(sp)-H bonds with -generated sulfenate anions is achieved to access chiral sulfoxides, which are found in the structures of many biologically active agents. The more challenging aliphatic C-H bonds as well as sterically hindered substrates containing tertiary C-H bonds could also be tolerated well. Mechanistic studies indicate that the transformation could undergo a CoS(O)R-mediated single-electron transfer with -fluorocarboxamides, followed by a 1,5-hydrogen atom transfer and then a pivotal organocobalt(IV)-controlled enantioselective cross-coupling process.

Electrochemical meta-C-H sulfonylation of pyridines with nucleophilic sulfinates.

Considering the indispensable significance and utilities of meta-substituted pyridines in medicinal, chemical as well as materials science, a direct meta-selective C-H functionalization of pyridines is of paramount importance, but such reactions remain limited and highly challenging. In general, established methods for meta C-H functionalization of pyridines rely on the utilization of tailored electrophilic reagents to realize the intrinsic polarity match. Herein, we report a complementary electrochemical methodology; diverse nucleophilic sulfinates allow meta-sulfonylation of pyridines through a redox-neutral dearomatization-rearomatization strategy by a tandem dearomative cycloaddition/hydrogen-evolution electrooxidative C-H sulfonation of the resulting oxazino-pyridines/acid-promoted rearomatization sequence.

Assembly of Selenadiazine Scaffolds via Rh(III)-Catalyzed Amidine-Directed Cascade C-H Selenylation/[5 + 1] Annulation with Elemental Selenium.

By employing elemental selenium as the selenium source, we have realized the amidine-directed Rh(III)-catalyzed cascade C-H selenylation/[5 + 1] annulation for the direct construction of structurally novel selenadiazine, benzoselenadiazine, and benzoselenazol-3-amine frameworks with specific site selectivity and good functional group tolerance. Besides, the obtained products can serve as fundamental platforms for subsequent chemical transformations, and thus, the feasible SeNEx reaction, SeNEx/Michael addition, and simple conversion of the selenadiazine product into diverse other organoselenium molecules were demonstrated accordingly. Taken together, the developed methodology efficiently expands the chemical space of organoselenium species.

Rhodium-Promoted C-H Activation/Annulation between DNA-Linked Terminal Alkyne and Aromatic Acid: A Finding from the Selection Outcomes.

Inspired by previous selection outcomes, we investigated and developed a rhodium-promoted C-H activation/annulation reaction of DNA-linked terminal alkynes and aromatic acids. This reaction exhibits excellent efficiency with high conversions and a broad substrate scope. Most importantly, the unique DEL-compatible conditions provide a better scenario for yielding an isocoumarin scaffold compared to conventional organic reaction conditions, and this newly developed on-DNA method has confirmed its feasibility in preparing DNA-encoded libraries.

Carbene-Mediated Polymer Modification Using Diazo Compounds under Photo or Thermal Activation Conditions.

Based on the characteristics of commodity polymers in large quantities and low costs, modification of existing commodity polymers emerges as the most effective approach for exploring novel materials. Nevertheless, conventional modification methods typically involve high-energy processes (e.g.

Silver Surface-Assisted Dehydrobrominative Cross-Coupling between Identical Aryl Bromides.

Cross-coupling reactions represent an indispensable tool in chemical synthesis. An intriguing challenge in this field is to achieve selective cross-coupling between two precursors with similar reactivity or, to the limit, the identical molecules. Here we report an unexpected dehydrobrominative cross-coupling between 1,3,5-tris(2-bromophenyl)benzene molecules on silver surfaces.

Visible-Light-Promoted Cascade Coupling of 2-Isocyanonaphthalenes with Elemental Sulfur and Amines to Construct Naphtho[2,1-d]thiazol-2-Amines.

A visible-light-induced strategy has been explored for the synthesis of naphtho[2,1-d]thiazol-2-amines through ortho-C-H sulfuration of 2-isocyanonaphthalenes with elemental sulfur and amines under external photocatalyst-free conditions. This three-component reaction, which utilizes elemental sulfur as the odorless sulfur source, molecular oxygen as the clean oxidant, and visible light as the clean energy source, provides a mild and efficient approach to construct a series of naphtho[2,1-d]thiazol-2-amines. Preliminary mechanistic studies indicated that visible-light-promoted photoexcitation of reaction intermediates consisting of thioureas and DBU might be involved in this transformation.

Mask and Release Strategy-Enabled Diversity-Oriented Synthesis for DNA-Encoded Library.

An ideal DNA-encoded library (DEL) selection requires the library to consist of diverse core skeletons and cover chemical space as much as possible. However, the lack of efficient on-DNA synthetic approaches toward core skeletons has greatly restricted the diversity of DEL. To mitigate this issue, this work disclosed a "Mask & Release" strategy to streamline the challenging on-DNA core skeleton synthesis.

Growth Control Strategy of Hydrogen-Containing Nanocrystalline Carbon Films during Plasma-Enhanced Chemical Vapor Deposition based on Molecular Dynamics-Monte Carlo Simulations.

Hydrogen-containing nanocrystalline carbon films (n-C:H) with amorphous-nanocrystalline hydrocarbon composite structures exhibit excellent properties in diverse applications. Plasma-enhanced chemical vapor deposition (PECVD) is commonly employed to prepare n-C:H films due to its ability to create an adjustable deposition environment and control film compositions. However, the atomic-scale growth mechanism of n-C:H remains poorly understood, obstructing the design of the appropriate deposition parameters and film compositions.

Controlling Metal-Oxide Reducibility for Efficient C-H Bond Activation in Hydrocarbons.

Knowing the structure of catalytically active species/phases and providing methods for their purposeful generation are two prerequisites for the design of catalysts with desired performance. Herein, we introduce a simple method for precise preparation of supported/bulk catalysts. It utilizes the ability of metal oxides to dissolve and to simultaneously precipitate during their treatment in an aqueous ammonia solution.

High-efficiency visible-light-driven oxidation of primary C-H bonds in toluene over a CsPbBr perovskite supported by hierarchical TiO nanoflakes.

Photocatalytic oxidation of toluene to valuable fine chemicals is of great significance, yet faces challenges in the development of advanced catalysts with both high activity and selectivity for the activation of inert C(sp)-H bonds. Halide perovskites with remarkable optoelectronic properties have shown to be prospective photoactive materials, but the bulky structure with a small surface area and severe recombination of photogenerated electron-hole pairs are obstacles to application. Here, we fabricate a hierarchical nanoflower-shaped CsPbBr/TiO heterojunction by assembling CsPbBr nanoparticles on 2D TiO nanoflake subunits.

Iodine-Mediated α-C-H Amination of Carbonyl Compounds via Nitrogen-Directed Oxidative Umpolung.

A new synthetic strategy for direct C()-H amination of carbonyl compounds at their α-carbon has been established employing molecular iodine and nitrogen-directed oxidative umpolung. In this transformation, iodine acts not only as an iodinating reagent but also as a Lewis acid catalyst, and both the nitrogen-containing moiety and the carbonyl group in the substrate play important roles. This synthetic approach is applicable to a broad variety of carbonyl substrates, including esters, ketones, and amides.

Synthesis of Polysubstituted Furan Frameworks via [3 + 2] Annulation of -Enoxyimides with Chelated Alkynes Initiated by Rh(III)-Catalyzed C-H Activation.

A variety of 2,3,5-trisubstituted furans were synthesized by virtue of a Rh(III)-catalyzed vinylic C-H coupling of -enoxyimides with propargyl alcohols or amines. In this protocol, -enoxyimides served as a one-oxygen and two-carbon synthon and the -OH/-NHR moiety in the alkynes was found to be crucial for realizing the desired chemo-/regioselectivity. Detailed experimental mechanistic studies together with DFT calculations clarified the sequential C-H activation/regioselective alkyne insertion/simultaneous O-N bond cleavage and hydrogen transfer/intramolecular nucleophilic addition/aromatization reaction path, which involved a distinctive Rh(V) carbene species as the active intermediate.