Structurally and electronically driven uniaxial negative thermal expansion in BaIrO.

Negative thermal expansion is known to exist in a range of structure types but is extremely rare in hexagonal perovskites. Here we demonstrate that BaIrO displays negative linear thermal expansion in the direction of its face-shared IrO trimers, and apparent zero volume thermal expansion below 100 K. We present evidence that this anomalous thermal expansion is driven by an unusual form of rigid body phonon behaviour governed by the effective trimer valence state and therefore has structural and electronic components to the underlying mechanism.

Luminescent terbium(III) probes containing an aromatic amino acid-based antenna for discrimination between adenine and guanine nucleotides.

Herein we present a series of luminescent Tb(III)-probes ([Tb-Ltrp], [Tb-Ltyr], and [Tb-Lphe]) for sensing and discriminating purine nucleoside polyphosphates (NPP) based on a modified DTTA chelator appended to aromatic amino acids (Laa). The optically most effective luminescent [Tb-Ltrp] probe preferentially discriminates the guanine-NPPs over the adenine-NPPs PeT-based modulation of Tb(III) luminescence within the biological concentration range.

Biaxially chiral compounds: research and development of synthesis.

With the rapid advancements in asymmetric catalysis, there is a growing need for the asymmetric selective synthesis of complex and diverse molecules with chiral axes. Axially chiral molecules are not only present in natural products and drugs but also in specialized chiral ligands and catalysts. The catalytic asymmetric synthesis of axially chiral molecules has garnered significant attention within the chemical community.

Palladium-catalyzed distal γ- and ε-benzylation, allylation and allenylation of enones.

We report herein a palladium-catalyzed distal alkylation of silyldienol and silyltrienol ethers of enones through coupling with activated halides to achieve new - and -alkylated motifs. Additionally, by employing propargyl bromides, synthetically useful linear allenes along with functionalized enones have been synthesized. Low-catalyst loading, and late-stage transformations of pharmaceutically relevant molecules further showcase the importance of the present protocol.

Diselenides as novel effective fluorescence quenchers to construct a two-photon fluorescent probe for thiols in a mouse stroke model.

A fluorescence quenching mechanism using linear diselenides was proposed for the first time through a combination of intramolecular charge transfer (ICT) and Förster resonance energy transfer (FRET). Herein, we synthesized and screened a two-photon fluorescent probe AFC-SeSe, demonstrating a remarkable 300-fold increase in response to glutathione (GSH). Additionally, AFC-SeSe enabled real-time observation of increased thiol levels following treatment within a short timeframe in a mouse model of stroke.

A covalent organic framework-based nanoreactor for enhanced chemodynamic therapy through cascaded Fenton-like reactions and nitric oxide delivery.

Herein, we report a nanoscale composite COF material loaded with copper peroxide (CuO) and nitric oxide (NO) prodrug a stepwise post-synthetic modification. The obtained CuO2@COF-SNO can undergo a cascade reaction in the tumor microenvironment to generate reactive oxygen and nitrogen species (ROS/RNS) to enhance chemodynamic therapy of the tumor.

Silane-promoted cycloaddition of thiobenzhydrazides with carbon dioxide toward 1,3,4-thiadiazol-2(3)-ones.

Herein, we developed a silane-promoted cycloaddition of thiobenzhydrazides with carbon dioxide leading to 1,3,4-thiadiazol-2(3)-ones. This procedure involves sequential -silylation and fixation of carbon dioxide toward a hydrazine formyl intermediate, followed by intramolecular nucleophilic cyclization and aromatization. A series of functional groups are well-tolerated under this procedure.

Coordination-induced axial chirality controls the metal-centred configuration in a stereogenic-at-iron catalyst.

A new approach is introduced to control the metal-centred configuration of stereogenic-at-iron catalysts by utilizing axial ligand chirality, which becomes locked upon metal coordination. This strategy is applied to an iron catalyst containing two chelating -(2-pyridyl)-substituted triazol-5-ylidene mesoionic carbenes (MICs) resulting in a helical topology with a stereogenic iron centre.

Immunoadjuvant-functionalized metal-organic frameworks: synthesis and applications in tumor immune modulation.

Cancer immunotherapy, which leverages the body's immune system to recognize and attack cancer cells, has made significant progress, particularly in the treatment of metastatic tumors. However, challenges such as drug stability and off-target effects still limit its clinical success. To address these issues, metal-organic frameworks (MOFs) have emerged as promising nanocarriers in cancer immunotherapy.

The steric hindrance effect of Co porphyrins promoting two-electron oxygen reduction reaction selectivity.

A new Co 5,10,15,20-tetrakis(2',6'-dipivaloyloxyphenyl)porphyrin (1) with eight ester groups in all and ' positions of phenyl groups was designed, which displayed significantly improved 2e oxygen reduction reaction (ORR) selectivity compared with a 5,10,15,20-tetrakis(-dipivaloyloxyphenyl) porphyrin (2) without large steric groups. This work is significant to reveal the steric hindrance effect of metal porphyrins on electrocatalytic ORR selectivity.

Transition-metal-free dibenzoxazepinone synthesis by hypervalent iodine-mediated chemoselective arylocyclizations of -functionalized salicylamides.

We have developed transition-metal-free synthetic methodologies for dibenzoxazepinones utilizing salicylamides as starting materials and employing two distinct types of successive hypervalent iodine-mediated arylocyclizations. This synthetic protocol encompasses selective phenol -arylation of salicylamides with diaryliodonium salts, followed by electrophilic aromatic amination utilizing chemically or electronically generated hypervalent iodine reagents in the second stage of the process.

A biocompatible Ni(II) complex as an amyloid sensor for human PrP fibrillar aggregates.

KRS-1, a biocompatible nickel(II) complex, is introduced as a potent fluorescent probe for PrP fibrillar aggregates. KRS-1 shows a 15-fold enhancement in PL intensity and detects all stages of PrP aggregation. Fluorescence microscopy confirms its efficacy in identifying PrP fibrillar aggregates in HT-22 cells.

Unleashing the potential of rare earth ions in modified calcium titanate for strategic anti-counterfeiting application.

Technological advancements have intensified the demand for effective counterfeiting protection. This work presents multi-level security features in a (Ca,Zn)TiO:Pr,Er phosphor. A dual doping strategy synergistically results in dynamically changing luminescence emission.

Bithiophene dicarboxylate as an efficient organic anode material for sodium-ion batteries.

In this study, new carboxylates are synthesized for sodium-ion batteries. The bithiophene-based anode material BT demonstrates a high reversible capacity of 201 mA h g and excellent durability. BT retains 99.

Recent progress of density functional theory studies on carbon-supported single-atom catalysts for energy storage and conversion.

Single-atom catalysts (SACs) have become the forefront and hotspot in energy storage and conversion research, inheriting the advantages of both homogeneous and heterogeneous catalysts. In particular, carbon-supported SACs (CS-SACs) are excellent candidates for many energy storage and conversion applications, due to their maximum atomic efficiency, unique electronic and coordination structures, and beneficial synergistic effects between active catalytic sites and carbon substrates. In this review, we briefly review the atomic-level regulation strategies for optimizing CS-SACs for energy storage and conversion, including coordination structure control, nonmetallic elemental doping, axial coordination design, and polymetallic active site construction.

Single-wall carbon nanotube separations aqueous two-phase extraction: new prospects enabled by high-throughput methods.

Aqueous two-phase extraction (ATPE) is an effective and scalable liquid-phase processing method for purifying single species of single-wall carbon nanotubes (SWCNTs) from multiple species mixtures. Recent metrological developments have led to advances in the speed of identifying solution parameters leading to more efficient ATPE separations with greater fidelities. In this feature article, we review these developments and discuss their vast potential to further advance SWCNT separations science towards the optimization of production scale processes and the full realization of SWCNT-enabled technologies.

Lithium salt-derived artificial near-surface reconfiguration to stabilize high-voltage LiCoO.

Pushing the limit of the charging cut-off voltage inevitably leads to the instability of bulk and interfacial structures. Herein, one-step dual-modified LiCoO (LCO) is achieved by thermodynamic decomposition of lithiuim salts on the surface, featuring F-doped bulk and LiF & LiBO coating layers. Notably, such artificial near-surface reconfiguration effectively suppresses Co dissolution, structural deconstruction and electrolyte side reactions during repeated lithiation/delithiation processes.

Two novel lanthanide metal-organic frameworks based on tetraphenylethylene for ultra-high proton conduction.

Two novel isostructural anionic lanthanide metal-organic frameworks, (MeNH)[Ln(HTCBPE-F)·(HCOO)·DMF]·4.5DMF·2HO (Eu-MOF and Dy-MOF), based on tetraphenylethylene carboxylate ligands were successfully constructed and characterized. These two MOFs possess porous structures and water stabilities with uncoordinated carboxylate groups and dimethyl ammonium cations, which allow for high proton conductivities (5.

Photoinduced ligand-to-metal charge transfer (LMCT) in organic synthesis: reaction modes and research advances.

In recent years, visible light-induced ligand-to-metal charge transfer (LMCT) has emerged as an attractive approach for synthesizing a range of functionalized molecules. Compared to conventional photoredox reactions, photoinduced LMCT activation does not depend on redox potential and offers diverse reaction pathways, making it particularly suitable for the activation of inert bonds and the functional modification of complex organic molecules. This review highlights the indispensable role of photoinduced LMCT in synthetic chemistry, with a focus on recent advancements in LMCT-mediated hydrogen atom transfer (HAT), C-C bond cleavage, decarboxylative transformations, and radical ligand transfer (RLT) reactions.

A high performance MBene substrate for improving the MnO cathodes for aqueous Zn-ion batteries.

Slow kinetics and instability seriously hinder the development of MnO cathodes for aqueous Zn-ion batteries. Herein, an emerging 2D material MoB-based MBene was used as the MnO matrix. Benefiting from the high electrical conductivity and outstanding stability of MoB, the prepared MoB/MnO composite cathode effectively alleviated the above issues and showed significant electrochemical performance improvement.

Green solvent strategies for the sustainable development of perovskite solar cells.

Perovskite solar cells have been of great interest over the past decade, reaching a remarkable power conversion efficiency of 26.7%, which is comparable to best performing silicon devices. Moreover, the capability of perovskite solar cells to be solution-processed at low cost makes them an ideal candidate for future photovoltaic systems that could replace expensive silicon and III-V systems.

Post-synthetic modification of amine-functionalized permanently porous coordination cages.

This manuscript explores the post-synthetic modification (PSM) of amine-functionalized porous coordination cages, specifically focusing on the formation of imine bonds through reactions with aldehydes. Targeting various cage topologies, including zirconium-, magnesium-, and molybdenum-based structures, we demonstrate the tunability of cage solubility and porosity through selective functionalization where the proximity of amine groups on the parent cage impacts the extent of modification. The work highlights the reversible nature of imine formation, offering potential applications in solubility switching and mixed-metal solid synthesis.

Advances in cross-coupling and oxidative coupling reactions of NH-sulfoximines - a review.

Due to the special structure and physicochemical properties of sulfoximines, research on sulfoximines has achieved great progress in recent decades, especially in chemical and medicinal fields. This review highlights recent advancements in the N-functionalization of NH-sulfoximines, focusing on classical cross-coupling reactions with electrophilic agents and oxidative coupling reactions with extensive organic compounds, including specific (hetero)arenes, alkenes (1,4-naphthoquinones), alkanes (cyclohexanes), nucleophiles (thiols, disulfides, sulfinates, diarylphosphine oxides), organyl boronic acids, and arylhydrazines. Transition metal-catalyzed, metal-free, electrochemical and radical oxidative coupling reactions are discussed.