A stereoselective and enantiospecific synthesis of trisubstituted 1,3a,4,6a-tetrahydropentalenes via Rh(I)-catalyzed skeletal editing of optically active 2,6-disubstituted cuneanes are reported. These are derived from achiral 1,4-disubstituted cubanes through a catalytic asymmetric framework isomerization. The method provides concise access to chiral diene ligands from symmetric cage-type hydrocarbons.

Cage-type hydrocarbons represented by cubane serve as molecular scaffolds for various useful molecules, such as pharmaceuticals and organocatalysts. However, even for the most readily available cubane, achieving regioselective substitution and controlled induction of chirality remains extremely challenging. A method to access chiral motifs using achiral 1,4-disubstituted cubanes, highly symmetric cage-type molecules, as starting materials has been developed. Through asymmetric isomerization of their molecular frameworks, these cubanes are converted into optically active 2,6-disubstituted cuneanes. Subsequently, treatment with nucleophiles, such as alcohols and 1,3-diketones, in the presence of a rhodium catalyst enables the stereoselective and enantiospecific synthesis of trisubstituted 1,3a,4,6a-tetrahydropentalenes via skeletal isomerization accompanied by nucleophilic addition. This cuneane scaffold editing strategy provides an efficient synthetic route to chiral 1,3a,4,6a-tetrahydropentalenes bearing substituents. These compounds show promise as asymmetric, cage-derived, bowl-shaped diene ligands.

Nanogels formed through self-assembly, microemulsion, or precipitation polymerization method enable precise delivery of immunotherapeutic factors and immune cell targeting, thus effectively modulating immune responses. This review highlights recent advances in stimuli-responsive nanogel design, underlying mechanisms, and their potentials to tackle cancer and inflammatory diseases with improved immunotherapy efficacy, as well as discusses the associated challenges and outlooks.

Immunotherapy, despite its notable therapeutic potential in cancer and inflammatory diseases, still faces challenges in clinical efficacy due to the complexity of tumor or inflammatory microenvironment. Nanogels (NGs) have emerged as a versatile therapeutic platform, owing to their unique structural advantages, including high drug encapsulation capacity, easy surface modification, stimuli-responsiveness, and excellent biosafety, collectively addressing critical limitations of conventional immunotherapy delivery systems. Herein, the advances in functional NG design and synthesis for immunomodulation to treat cancer and inflammatory diseases are reviewed. The mechanisms of NGs in immunotherapy are mainly elucidated including immunotherapy factor delivery systems enabling precise payload release, the immune modulation through both activation and suppression, and targeting strategies at immune cell levels. Finally, the challenges and application prospects of NG-based nanoplatforms in the treatment of cancer and inflammatory diseases are briefly discussed.

A small library of tricyclic natural product-like molecules with quaternary stereocenters is rapidly synthesized. An excellent chirality transfer from sulfur to carbon atom is observed, furnishing the desired products in 90–99% enantiomeric excesses and 51–78% isolated yields. The feasibility of our new asymmetric methodology is highlighted by the total synthesis of myrmenaphthol A, a natural product isolated from a Hawaiian sponge.

The asymmetric total synthesis of myrmenaphthol A, a natural product isolated from a Hawaiian sponge of the genus myrmekioderma, has been achieved in 12 steps. The key transformation of this synthesis is a gold-catalyzed [3,3]-sigmatropic rearrangement of sulfonium, starting from a chiral sulfoxide substrate and propargyl silane. The development of the methodology includes the synthesis of benz[e]inden-2-one derivatives with quaternary centers (51–78% yield, 90%–99% ee).

Dynamic NMR and trapping studies reveal that POCOP–Ir phenyl hydride complexes perform reductive coupling rapidly but dissociate benzene slowly. PCP–Ir analogs show comparatively slow reductive coupling and faster dissociation. This work experimentally clarifies aspects of C–H reductive elimination in iridium pincer complexes.(POCOP = bisphosphinite,pincer ligand PCP = phosphine pincer ligand)

Oxidative addition and reductive elimination are fundamental processes in organometallic chemistry and are important in catalytic transformations involving C–H bonds. Herein, the article reports on the dynamics of benzene reductive elimination from iridium complexes bearing bisphosphinite (POCOP) and phosphine (PCP) based pincer ligands. The reductive elimination forms an important 14-electron catalytic intermediate that has eluded detection. Using NMR spectroscopy, including dynamic 31P NMR and 1D/2D exchange spectroscopy experiments, it is demonstrated that in POCOP-Ir(Ph)H complexes reductive coupling and benzene dissociation are experimentally separable steps, with reductive coupling being fast and dissociation slow. In contrast, PCP-Ir(Ph)H exhibits slower reductive coupling and more facile dissociation. Rate constants and activation parameters for both processes are determined and trapping experiments with external olefins further quantifies dissociation kinetics. The data show that comparatively electron-poor POCOP complexes facilitate reductive coupling but inhibit ligand dissociation compared to electron-rich PCP analogs. These findings highlight mechanistic nuances in exchange processes, including differences in resting states for dehydrogenation, and demonstrate the importance of directly identifying the step being measured in dynamic NMR studies.

In this study, the synthesis and detailed photophysical characterization of SiNcs functionalized with structurally diverse axial ligands designed to enhance solubility and evaluate photophysical properties are reported. The lead compound, SiNc 3-PP, demonstrates photothermal conversion efficiency of 62.1% and pronounced photoacoustic contrast at 810 nm, highlighting its potential as an efficient theranostic agent.

Naphthalocyanines are emerging as highly promising photosensitizers, owing to their intensive absorption (ε > 1 × 105 M−1 cm−1) beyond 800 nm, but their poor solubility in biological media has significantly limited their clinical translation. In this study, the synthesis and detailed photophysical characterization of silicon naphthalocyanines (SiNcs) functionalized with structurally diverse axial ligands designed to enhance solubility and evaluate photophysical properties for theranostic applications are reported. Through an efficient synthetic approach, a library of SiNc derivatives are generated and systematically evaluated for their Q-band absorption shift, absolute fluorescence quantum yields, lifetime, radiative decay rate, and singlet oxygen generation. The lead compound, SiNc 3, is encapsulated in poly(ethylene glycol)-b-poly(ε-caprolactone) (PEG-PCL) micelles to improve biocompatibility and in vivo delivery. Axial ligand modifications are found to influence aggregation behavior within the nanoformulation, enabling SiNc 3-PP to retain a strong and sharp absorption peak at 810 nm and exhibit high photothermal conversion efficiency (62.1%). SiNc 3-PP demonstrates strong photoacoustic imaging contrast at 810 nm, and upon near-infrared irradiation in tumor-bearing mice, induced rapid tumor heating up to 54 °C within 5 min, resulting in significant tumor growth inhibition. These findings underscore the pivotal role of axial ligand engineering in tuning SiNc behavior and highlight their potential as theranostic agents integrating photoacoustic imaging and photothermal therapy.

Tracking the propagation of periodic concentration perturbations within chemical reactions is presented as a powerful strategy for probing reaction connectivity and the kinetics of individual reaction steps. This approach is demonstrated here for the organocatalytic Michael-type addition of cyclopentadiene to α,β-unsaturated aldehydes, based on relative phase delays in ion intensities measured by electrospray ionization–mass spectrometry.

Periodic perturbations, such as modulations of reactant concentration, propagate through chemical reactions with distinct phase delays. Tracking the propagation of such perturbations presents a powerful approach for probing the reaction connectivity and the rates of individual reaction steps, provided that high-throughput and information-rich analytical approaches are used. Here, the online monitoring of periodic perturbations in the organocatalytic addition of cyclopentadiene to α, β-unsaturated aldehydes by electrospray ionization–mass spectrometry (ESI–MS) is reported. Upon perturbation of input concentrations, ion intensities corresponding to substrates and reaction intermediates detected by ESI–MS exhibit characteristic time delays, providing insights into the kinetics of individual reaction steps, as supported by numerical simulations. This study provides a novel framework for online reaction monitoring and mechanistic analysis in chemical systems.

A redox-active Cu(I)-photocatalyst is evaluated for the aziridination of alkenes. Especially styrenes and electron-rich 1,3-dienes are found to be suitable substrates, allowing short reaction times (10 min) at low catalyst loading (1 mol%). The activation of the copper(I) complex by light is compared to the process in the dark.

The direct aziridination of alkenes using iminoiodinanes as nitrogen source is successfully achieved by applying the copper(I) complex [Cu(dmp)2]Cl (dmp = 2,9-dimethyl-1,10-phenanthroline), being an established photocatalyst. The copper complex exhibits high activity in the dark for aziridination, complementing recently reported photoredox-catalyzed aziridinations with Ru(bpy)3Cl2, which enables the transformation to occur at room temperature with low catalyst loading (1 mol%) and short reaction times (down to 10 min). Notably, the aziridine derived from α-methyl styrene undergoes visible-light-driven, copper-catalyzed atom transfer radical addition to yield functionalized amines, highlighting the dual role of [Cu(dmp)2]Cl as both aziridination and photoredox catalyst for streamlined synthesis to complex nitrogen-containing scaffolds.

Analyze the storage mechanism of hard carbon materials in alkali metal ion batteries, explore the relationship between microstructure and performance, and provide countermeasures to improve performance.

Hard carbons (HCs) are nongraphitizable and consist of numerous short-range carbon layers stacked together. The carbon layers are twisted around each other and form large layer spacing as well as diverse pore types, making it ideal for extensive application in alkali metal ion batteries (AMIBs). However, the impact of complex microstructure on alkali metal ion storage has not been fully recognized, which is not conducive to the improvement of electrochemical properties of HCs. Therefore, this article not only systematically analyzes the ion storage mechanism of HCs in AMIBs but also focuses on the relationship between the microstructure (graphite microcrystals, defects, and nanopores) and the electrochemical performance of HCs. Subsequently, it provides countermeasures to the problems of the electrochemical properties. Finally, the key challenges and perspectives for high-performance HC anodes are also discussed.

Blurring the boundaries between main-group and transition metal chemistry, Group 14 metallylenes offer a tunable, earth-abundant platform for catalysis. Once the domain of d-block elements, transition metal-like reactivity is now within reach—unlocking new avenues for sustainable small-molecule activation and follow-up reactions through ligand optimization and quantum chemical design. More information can be found in the Review by T. A. Hamlin and co-workers (DOI: 10.1002/ceur.202500119).

The Front Cover shows a round-bottomed flask containing a burgundy solution of diferrocenylphosphenium ion [Fc2P][B(C6F5)4], which was used in this work to activate various allenes. Dropwise addition to 2-(trimethylsilyl) penta-2,3-diene yields a bright red solution of a stable Wheland intermediate of ferrocene, whose solid-state structure is depicted as a ball-and-stick model. In front lies Saint Peter’s Key, a prominent feature of the City of Bremen’s coat of arms, representing the unlocked potential of highly reactive main group species. More information can be found in the Research Article by E. Hupf, J. Beckmann and co-workers (DOI: 10.1002/ceur.202500031).