Two-dimensional covalent organic frameworks (2D COFs) have attracted increasing research attention in photocatalysis-related fields due to their high porosity, large surface area, and tunable band gap. The construction of effective and robust 2D COFs for improving photocatalytic activity of 2D COFs is highly desirable. Herein, we propose a strategy for promoting photocatalytic oxidative activity of 2D COFs via doping nitrogen into donor units. Two novel benzothiadiazole-based 2D COFs with kgm topology, namely COF−BD and COF−BP, have been successfully synthesized by reacting tetratopic 5,5'-(benzo[c][1,2,5]thiadiazole-4,7-diyl)diisophthalaldehyde with ditopic benzidine and [2,2'-bipyridine]-5,5'-diamine, respectively. Interestingly, the as-synthesized COF−BP exhibited better performances in photocatalytic oxidative coupling of amines than the corresponding COF−BD. Moreover, the resultant COF−BP exhibited excellent recyclability after being used for ten cycles. Mechanistic investigations revealed that the introduction of electron-withdrawing nitrogen atoms into donor units is favorable for enhancing visible-light absorption, narrowing the band gap, and facilitating the separation and transport of the photogenerated carriers of 2D COFs. This work provides an effective approach for the design of 2D COFs for advanced photocatalytic organic transformations.

Ethane-selective adsorbents enable the direct production of high-purity C₂H₄ in a single step, showcasing substantial research potential. In this work, we report the synthesis of two hydrogen-bonded organic frameworks (HOFs), NKM-HOF-6 and NKM-HOF-7, featuring permanent microporosity. Upon treatment with hot acetone, NKM-HOF-6 undergoes a structural transformation into NKM-HOF-7, characterized by a transition from a 3D polycatenated framework to a 2D parallel displacement-stacked structure. This transformation leads to a reduction in the maximum pore size of NKM-HOF-7 and a decrease in the density of -CF₃ groups within its channels, thereby enhancing its preferential affinity for C₂H₆ over C₂H₄. The adsorption capacity difference between C₂H₆ and C₂H₄ in NKM-HOF-7 is 11.1 cm³·g^–1, with an IAST selectivity of 1.77, surpassing the corresponding values for NKM-HOF-6 (9.6 cm³·g^–1 and 1.56, respectively). Breakthrough experiments further reveal that NKM-HOF-7 achieves nearly twice the separation efficiency of NKM-HOF-6 for C₂H₆/C₂H₄ (10/90, V/V) mixtures. Theoretical calculations attribute this enhanced C₂H₆ affinity to the synergistic effects of optimized pore dimensions and functionalized pore surfaces in NKM-HOF-7. These findings provide critical insights for the rational design of highly efficient C₂H₆-selective adsorbents.

Herein, we report a base-promoted, silylborane-mediated strategy for the transformation of fluorinated carbenes derived from fluoroalkyl ketones, enabling the efficient and stereoselective synthesis of diverse fluorinated 1,3-dienes and alkenes. This metal-free protocol exhibits broad functional group tolerance, accommodating halogens, heteroarenes, and various perfluoroalkyl groups, providing streamlined access to fluorinated frameworks that are otherwise challenging to obtain using conventional methods. Mechanistic studies support a silyl radical-initiated pathway, wherein t-BuONa promotes the in-situ generation of silyl radicals that abstract allylic C–H bonds, triggering downstream selective defluorination. This work establishes a practical platform for the synthesis of valuable fluorinated building blocks and offers insights into silyl radical-driven transformations under metal-free conditions.

The rapid advancement of artificial intelligence and the Internet of Things has precipitated an urgent demand for renewable energy sources and portable electronic devices in contemporary society. Organic photovoltaic cells (OPVs), noted for their thinness, flexibility, and potential for large-scale manufacturing, have emerged as a promising technology for the direct conversion of solar energy into electrical power. However, current research in OPVs predominantly focuses on enhancing power conversion efficiency (PCE), while the inherent mechanical brittleness of OPV films significantly constrains their applicability in stretchable electronics, thereby impeding their further development and practical implementation. To address this challenge, we show an elastic additive with high fracture strain and low modulus to make both polymer:small molecule (PM6:PY-IT) and all-polymer (PM6:N2200) OPV films stretchy. The resulting intrinsically stretchable OPVs derived from these delicately tuned films demonstrate exceptional photovoltaic performance, with a top PCE of 13.84%, alongside remarkable stretchable stability (strain at 80% efficiency breaking 50%), indicated by the ability to maintain efficiency retention up to 0.8 fold even after 500 cycles of stretching at 30% tensile strain. This work not only offers a new strategy for enhancing the mechanical and photovoltaic properties of multifunctional organic electronic systems but also provides a concrete pathway for advancing OPVs toward practical employment.

Strain-release ring-opening trifluoromethylthiolation to construct SCF₃-substituted cyclic motifs was under-explored, and di-trifluoromethylthiolation is unachieved. Herein, we present the first trifluoromethylthiolation of bicyclo[1.1.0]butane (BCB) and bicyclo[2.1.0]pentane. By employing different activators, both mono- and di-trifluoromethylthio substituted cyclobutane and cyclopentane derivatives were successfully obtained.

Phase transition materials, which enable the switching of physical properties like second harmonic generation (SHG), have attracted great interest due to their wide applications, such as in sensors. However, although significant progress has been made in crystalline SHG switching phase transition materials, these materials typically show poor mechanical flexibility, hindering their applications in flexible wearable devices. Herein, for the first time, we reported a bendable photoluminescent molecular crystal (R)-octan-2-yl(E)-4- ((4-(hexadecyloxy)-2-hydroxybenzylidene)amino)benzoate (R-EHAB), which shows a phase transition at around 320 K, accompanied by obvious SHG switching between high-SHG and low-SHG states. Significantly, R-EHAB demonstrates a low elastic modulus of 3.03 GPa, which is much lower than that of most molecular phase transition crystals. This enables its crystals to be easily bent into a semicircular shape and remain unchanged after bending-recovery cycles. To our knowledge, R-EHAB is the first bendable molecular crystal with a phase transition accompanied by SHG switching. This work would inspire the further exploration of more bendable phase transition crystals for potential application in next-generation functional devices.

P,N-Atropisomers are valuable structural motifs, widely utilized as chiral ligands and in various catalytic systems. However, the asymmetric synthesis of these compounds from readily available starting materials remains a significant challenge. In this study, we present a chiral phosphoric acid-catalyzed atroposelective synthesis of axially chiral aminophosphines via dynamic kinetic resolution. This approach effectively addresses the aforementioned challenge through featuring the use of readily available starting materials, mild reaction conditions, high yields, excellent enantioselectivities, and a broad substrate scope, underscoring its practicality and synthetic utility.

The C(sp³)−O bond is a crucial structure frequently encountered in both natural products and synthetic molecules. Its cleavage plays a pivotal role in the degradation and conversion of plastics and biomass into valuable chemicals; this strategy can significantly alleviate the strain on our ecosystem while generating economic value. Herein, a novel protocol is reported for the degradation and transformation of polymers, namely, polyethylene glycol (PEG), into quinolines through the cleavage of C(sp³)−O bonds. Furthermore, air serves as the sole oxidant in the conversion process, thereby reducing conversion costs. This strategy offers a pathway to convert so-called "waste" materials into valuable chemicals and paves the way for innovative methods in the production of fine chemicals. Moreover, the scalability of this method has been demonstrated with the successful upcycling of expired commercial products into high-value-added products. To elucidate the mechanism behind this transformation, detailed mechanistic studies were performed, and a proposed mechanism was summarized and further supported by density functional theory calculations.

Planar organofluorine compounds are highly sought-after structural motifs. Herein, we present an enantioselective strategy for the synthesis of planar chiral fluoroalkenes via kinetic resolution of gem-difluorovinylferrocenes by copper-catalyzed hydrodefluorination in the presence of a base and diboron. This method was successfully applied to provide a diverse range of planar chiral gem-difluoroalkenes and Z-monofluoroalkenes with excellent regio-, stereo- and enantioselectivity. The resulting enantioenriched planar chiral fluoroalkenes could undergo various enantioretaining transformations, broadening their synthetic utility. Furthermore, density functional theory (DFT) calculations provide mechanistic insights into the origin of enantioselectivity, enhancing the understanding of this transformation.

A series of novel polymers based on highly twisted biphenyl imide and benzodithiophene have been designed and synthesized, exhibiting excellent thermal stability, strong absorption in the visible spectrum, and wide bandgaps. By strategically adjusting linkage positions and integrating thiophene bridges, the optical properties, energy levels of frontier orbitals, and interchain stacking of these polymers were meticulously tailored. Organic solar cells based on these polymer donors revealed that ZP4, featuring 4,4’-linkages and thiophene bridges, achieved the highest power conversion efficiency of 4.10%, which is comparable to that of analogous polymers based on more planar bithiophene imide. This study challenges the conventional belief that structural planarity is essential for high-performance OPV polymers, underscoring the potential of non-planar units and broader design strategies beyond planarity.

This study investigates elemental reactions of vanadium hydride {[^DippN₂NCH₂C₆H₄]VH}₂{K}₂ (1) toward CO, CO₂, and alkynes. Exposure of 1 to CO at −78 °C yielded the dicarbonyl divanadium complex {[^DippN₂NBn]V(CO)₂}₂{K}₂ (2), while heating at 100 °C afforded the CO homologation product {[^DippN₂NCH₂C₆H₄]V(THF)}₂(μ-κ²-C₂H₂O₂) (3). Reaction of 1 with CO₂ generated the dinuclear vanadium formate complex {[^DippN₂NCH₂C₆H₄]V(HCOO)}₂{K}₂ (5). Treatment of 1 with methyl phenylpropiolate produced the vanadium enolate complex {[^DippN₂NCH₂C₆H₄C(Ph)C(H)COOMe]V}{K(THF)₂} (6). This work demonstrates new observations of sequential insertion of CO or activated alkynes into both V–H and V-C_Ar bonds, elucidating fundamental reactivity paradigms for vanadium hydrides.

In the rapidly evolving field of advanced materials science, the development of optical polymers with high refractive index has attracted much attention. Among these optical polymers, cyclic olefin polymers (COPs) have stood out as a versatile platform owing to exceptional transparency, low birefringence, good heat resistance, low moisture absorption, and superior chemical resistance. However, they suffer from a relatively low refractive index, ranging from n = 1.52 to 1.54, which poses a challenge. In this contribution, we demonstrate that the incorporation of aromatic groups into the polymer backbone has opened up new horizons, particularly in the pursuit of materials with high refractive index. COPs with high refractive index and high glass-transition temperature (T_g) are prepared via ring-opening metathesis polymerization (ROMP) and subsequent hydrogenation. Notably, these all-hydrocarbon COPs are amorphous, have a wide T_g range of 30–282 °C, exhibit high thermal stability (T_d,5% = 414–471 °C), and possess significantly high refractive index (1.5815–1.6748 at 589 nm) and excellent optical transmittance (89.0%–95.3%), making them promising candidates for advanced optical applications.

We report a substrate-dependent annulation system where 6-substituents of 2H-1,4-benzoxazines dictate divergent pathways with ynamides. Non-methoxy substrates undergo TBSOTf/Zn(OTf)₂-catalyzed [2 + 2] annulation/ring expansion to form 2H-1,6-benzoxazocines, while 6-methoxy derivatives preferentially yield 4-aminoquinolines via a TBSOTf-catalyzed [4 + 2] annulation/deformylation pathway. This electronic effect-driven selectivity operates under mild conditions with high fidelity. The method provides orthogonal access to two medicinally important heterocycle classes from identical precursors, features broad functional group tolerance, demonstrates scalability (up to 1 mmol scale), and eliminates the need for transition metals. The selectivity may originate from the differential stabilization of intermediates by the 6-substituent.

Polymer fiber filters play a vital role in removing particulate matter (PM), reducing environmental risk factors and cardiovascular diseases. However, the contradiction between high filtration efficiency and low airflow resistance limits the filtration performance of polymer filters, while exacerbating the microplastic contamination. Herein, we proposed an interface polarization strategy to fabricate a biodegradable fiber membrane with a high relative dielectric constant to filter the PM in a high-efficiency and low-resistance way. The membrane was constructed by silk fibroin (SF) and wool fiber membrane (Wool), where the SF bonded on the wool surface to form a crosslinked network. Specifically, polar groups (-NH₂/-OH) on SF form a dynamic hydrogen-bonding network with airborne water molecules, enhancing the interface polarization and elevating the relative dielectric constant to 8.4. Based on this high dielectric constant, Wool loaded with 20 mg of SF (SF@Wool) reaches PM_0.3 filtration efficiency of 99.69%, with air resistance of 8 Pa. Meanwhile, SF@Wool exhibits filtration efficiency decay of less than 0.5% over 30 d, demonstrating excellent long-term stability. Furthermore, the biodegradable properties of SF@Wool effectively prevent microplastic pollution (it can be completely degraded in soil within 14 d after treatment with alkaline solution).

Aromatic ketones, such as 9-fluorenone (9-FO), are known for their high intersystem crossing quantum yields (Φ_ISC ≈ 1), rendering them highly valuable for photochemical reactions and dye-sensitized solar cells. However, their use as photosensitizers in biological contexts has been hindered by their low extinction coefficients, high excitation energies, and weak fluorescence. To address these limitations, we conjugated 9-FO with a fused-ring electron donor, resulting in an acceptor-donor-acceptor derivative IDT-9F. This strategy has successfully redshifted the absorption peak of 9-FO (380 nm) into the visible light range (498 nm) and significantly enhanced its light absorption capability (~310-fold) and fluorescence quantum yield (~100-fold). Furthermore, IDT-9F was encapsulated within pH-responsive nanoparticles using an acid-induced charge-reversal polymer as the amphiphilic matrix, and enabled fluorescence imaging-guided photodynamic inactivation of Gram-positive bacteria in acidic environment with a remarkable bacterial inhibition rate exceeding 99.9%.

The cross-Claisen condensation is a valuable method for synthesizing β-keto esters but is traditionally limited by the need for strong bases or preformed silyl ketene acetals (SKAs) or a narrow substrate scope. To address these challenges, we developed a mild, N-heterocyclic carbene (NHC)-catalyzed radical cross-Claisen condensation between acyl imidazoles and α-bromo esters. This protocol employs Mn-mediated single-electron reduction to generate persistent ketyl and α-carbonyl radicals, enabling efficient cross-coupling of two electrophiles under redox-neutral conditions. The reaction proceeds with broad functional-group tolerance and can be conducted in a one-pot manner directly from carboxylic acids, offering a practical platform for β-keto ester synthesis.

Thioesters and their derivatives serve as prominently featured structural units in biological molecules. However, the lack of an adaptable and efficient synthetic method has hindered their widespread application. In terms of atom- and step-economy, there is an urgent need for an efficient strategy with a wider range of substrates compared to previous methods. Herein, we report a visible-light-driven synthesis of structurally diverse thioesters from aryl thianthrenium salts and carboxylic acids, using tetramethylthiourea as both sulfur source and potent photoreductant. This strategy utilizes aryl thianthrenium salts as novel electrophiles, which can be readily prepared via regioselective C–H thianthrenation of arenes. Mechanistic studies reveal that excited-state thiourea has strong reducing ability and can undergo a facile SET process with aryl thianthrenium salts.

Perovskite solar cells (pero-SCs) face inherent challenges due to the presence of numerous defects on the solution-processed perovskite surfaces. Conventional passivation strategies cannot address its detrimental effects on interfacial charge extraction efficiency and long-term device stability. In this study, we introduce methoxy-functionalized derivative-PEAI (OMe-PEAI) as a bifunctional interfacial mediator for the post-treatment of perovskite surfaces in n-i-p structured organic-inorganic hybrid pero-SCs. The methoxy group in OMe-PEAI, acting as a Lewis base with available lone-pair electrons, effectively interacts with uncoordinated Pb²⁺ to mitigate interfacial defects. More importantly, the strong dipole moment inherent to OMe-PEAI induces a reduction in perovskite work function, achieving optimized energy level alignment at the perovskite/Spiro-OMeTAD interface and enabling strong interfacial electronic coupling. These synergistic effects collectively enhance interfacial charge carrier extraction while suppressing non-radiative recombination losses. The optimized small-area devices (0.062 cm²) demonstrated a high-power conversion efficiency (PCE) of 25.38% with minimized voltage deficits while corresponding perovskite modules (13.93 cm²) achieved a notable PCE of 21.57%. Furthermore, OMe-PEAI-modified devices exhibited remarkable stabilities, retaining 89% and 92% of initial efficiencies after thermal stress testing (85 °C for 512 h) and maximum power point tracking (500 h), respectively.

Microneedle electrochemical biosensors have emerged as a crucial technology for non-invasive biomarker detection, offering minimally invasive and real-time monitoring capabilities. These biosensors utilize a microneedle array to extract interstitial fluid, and integrate biological recognition elements (e.g., enzymes, antibodies) and electrochemical signal converters (e.g., current, resistance) to enable rapid and sensitive detection of various biomarkers like blood glucose, lactic acid, and electrolytes. Despite the commercialization of this technology in continuous blood glucose monitoring, challenges persist, including the need to balance needle length and mechanical strength, ensure long-term stability against biological contamination and enzyme inactivation, and optimize large-scale manufacturing processes. Future advancements are anticipated through interdisciplinary collaborations, leveraging artificial intelligence for data analysis and exploring biodegradable materials, to facilitate the transition of microneedle electrochemical sensors from research settings to clinical use and advance the field of personalized medicine. This review examines the historical development, design, manufacturing processes, sensing mechanisms, biomarker detection capabilities, and integration potential of microneedle electrochemical biosensors, while also addressing their application prospects and technical hurdles.

The pentafluorosulfanyl (SF₅) group, characterized by its high electronegativity, lipophilicity and unique octahedral geometry, has the potential to modify the physicochemical properties of both pharmaceuticals and agrochemicals. Recently, pentafluorosulfanyl-containing compounds have garnered increasing attention, and big progress has been made in the development of novel synthetic strategies for these compounds. Central to these advancements is the exploration of synthesis and novel reaction of radical pentafluorosulfanylation reagents. This account provides an overview of the gas-reagent-free practical synthesis and new reaction of pentafluorosulfanyl chloride (SF₅Cl) developed by our group.