Functionalized 1,4-cyclohexadienes are valuable synthetic intermediates, yet their direct assembly from arene feedstocks via dearomative 1,4-addition remains a daunting challenge. Among arene dearomatization strategies,...Functionalized 1,4-cyclohexadienes are valuable synthetic intermediates, yet their direct assembly from arene feedstocks via dearomative 1,4-addition remains a daunting challenge. Among arene dearomatization strategies, η-coordination chemistry has long been used but invariably delivers 1,2-adducts due to an inherent regiochemical bias. Herein, we report the first intermolecular dearomative 1,4-addition to simple, unactivated arenes using dual nucleophiles via η-coordination to chromium/molybdenum. By employing a labile iodine placeholder that blocks the inner-sphere reductive elimination, we override the innate 1,2-selectivity, enabling both dearomative 1,4-dialkylation and 1,4-hydroalkylation. The method features an extraordinarily broad arene scope, excellent functional-group tolerance, and predictable regioselectivity. Isolation of a key Mo(II)-I intermediate with single-crystal X-ray diffraction and sufficient control experiments supports the proposed outer-sphere pathway. Synthetic utility is well demonstrated by site-selective dearomatization within polyaromatics, late-stage drug modification, and total synthesis of alkaloids.
Herein, we report a Ni-mediated F,D-monofluoromethylation of (hetero)arenes from (pseudo)halide coupling partners. This new approach offers key advantages compared to traditional radiochemistry based on S2-type reactivit...Herein, we report a Ni-mediated F,D-monofluoromethylation of (hetero)arenes from (pseudo)halide coupling partners. This new approach offers key advantages compared to traditional radiochemistry based on S2-type reactivity with [F]fluoride. These include increased precursor stability and availability, obviating bespoke precursor syntheses, broad functional group tolerance, and the late-stage introduction of deuterium and fluorine-18 in a single step, all features facilitating early access to PET ligands for discovery campaigns. This novel protocol is applied to over 30 diverse substrates, including complex bioactive molecules, and is amenable to scale-up via a semiautomated protocol on a commercial platform, illustrated by isolation of a F,D-labeled PARP radiotracer.
Point source carbon capture contributes crucially to climate change mitigation; however, integrating CO capture with renewable energy sources to minimize energy consumption for sorbent regeneration and CO release poses s...Point source carbon capture contributes crucially to climate change mitigation; however, integrating CO capture with renewable energy sources to minimize energy consumption for sorbent regeneration and CO release poses significant challenges. Photoacid-based systems offer a light-regulated route to CO capture and release by using photonic energy to modulate acidity under mild conditions. Herein, efficient photodriven CO release systems are realized through the coassembly of amino-functionalized metal-organic frameworks (MOFs) and metastable photoacids. This optimized system released 12 mL of CO per mmol photoacid every cycle from flue gas within 3 min of light exposure and regenerates CO-capture ability during a 5 min dark period. A U-shaped continuous-flow prototype further enabled light-triggered CO release, delivering a CO release rate of 0.11 mL min from an effluent gas flow of 1.0 mL min.
The lithium-mediated nitrogen reduction reaction (Li-NRR) provides a promising strategy toward green NH synthesis. While the proton donors are essential for Li-NRR, their role in modulating the chemistry and structure of...The lithium-mediated nitrogen reduction reaction (Li-NRR) provides a promising strategy toward green NH synthesis. While the proton donors are essential for Li-NRR, their role in modulating the chemistry and structure of the solid-electrolyte interphase (SEI) is still poorly understood. Here, we utilize in situ Raman spectroscopy, combined with X-ray and SEM characterization, to decipher the Li-NRR process and solid electrolyte interphase (SEI) dynamics under operating conditions. It was revealed that the SEI evolves from solvent-derived organic composition to lithium salt-involved inorganic nature as the reaction proceeds. Furthermore, ethanol was found to critically govern the chemical composition and physical morphology of SEI by tuning the content of LiF and LiBO compounds. This inorganic identity of SEI in turn produces a thin, uniform, and compact electrode surface, which regulates the mass transport of N, Li, and proton donor to promote the Li-NRR performance. These results establish a direct and tunable link among ethanol content, SEI structure, and Li-NRR performance and envision the tailored engineering to achieve device-scale NH production.
Inverse temperature crystallization (ITC) is widely used to grow high-quality perovskite single crystals, yet prolonged thermal exposure during this process can introduce chemical instabilities that hinder controlled cry...Inverse temperature crystallization (ITC) is widely used to grow high-quality perovskite single crystals, yet prolonged thermal exposure during this process can introduce chemical instabilities that hinder controlled crystal growth. In this work, we uncover unexpected solvent-dependent redissolution of formamidinium lead iodide (FAPbI) during ITC. While a mixed γ-butyrolactone (GBL) and 2-methoxyethanol (2ME) solvent system beneficially enables α-FAPbI growth in ambient conditions, we discover that FAPbI facilitates an esterification reaction of the two solvents that modifies the coordination environment and destabilizes perovskite during extended heating. Lead iodide (PbI) deficiency effectively delays the redissolution process, resulting in reduced δ-FAPbI formation and stabilized growth of thin α-FAPbI single crystals. Single-crystal solar cells based on phase-pure α-FAPbI crystals achieve 22.99% power conversion efficiency, setting a record for such devices fabricated under ambient air conditions. These results reveal an overlooked solvent-precursor interaction during ITC and demonstrate stoichiometry control as a practical strategy for stabilizing α-FAPbI single crystals for high-performance photovoltaic applications.
Azulene, a nonbenzenoid aromatic isomer of naphthalene with exceptional optoelectronic properties, has long eluded general methods for selective functionalization, especially on its electron-deficient seven-membered ring...Azulene, a nonbenzenoid aromatic isomer of naphthalene with exceptional optoelectronic properties, has long eluded general methods for selective functionalization, especially on its electron-deficient seven-membered ring. Here, we overcome this limitation by introducing the first practical precursors to azulyne intermediates. In stark contrast to well-established benzyne chemistry, the synthesis of these azulyne precursors is far from trivial, demanding tailored strategies to construct their bicyclic frameworks. Computations reveal that 5,6- and 4,5-azulyne possess substantial yet manageable ring strain and marked electrophilicity. Leveraging these versatile intermediates, we develop a modular platform that enables direct, efficient, and site-selective incorporation of diverse functionalities onto the azulene core through cycloadditions, nucleophilic additions, σ-bond insertions, and transition-metal-catalyzed reactions. This strategy grants unprecedented access to a wide range of polysubstituted azulenes and complex azulene-embedded polycyclic aromatic compounds (PACs), with regioselectivity governed by predictable steric and electronic principles. Our work transforms azulene from a synthetically challenging motif into a programmable building block based on this unique nonalternant architecture.
Linkage design is a decisive factor in determining the stability and function of covalent organic frameworks (COFs). Herein, we report oxazine-locked two-dimensional COFs constructed via an irreversible cascade reaction...Linkage design is a decisive factor in determining the stability and function of covalent organic frameworks (COFs). Herein, we report oxazine-locked two-dimensional COFs constructed via an irreversible cascade reaction integrating consecutive Pinner and Schiff base reactions. This design couples framework crystallization with permanent linkage formation, yielding COFs with high chemical robustness under acidic and basic conditions. These frameworks act as efficient photocatalysts for HO generation, illustrating a general synthetic route for stable COF-based photocatalysts in artificial photosynthesis.
Ion transport in solids is a key determinant of next-generation energy technologies, especially solid-state batteries, fuel cells, and other electrochemical systems. However, designing a superionic conductor remains chal...Ion transport in solids is a key determinant of next-generation energy technologies, especially solid-state batteries, fuel cells, and other electrochemical systems. However, designing a superionic conductor remains challenging because ionic conductivity arises from a coupled interplay among migration barriers, hopping frequencies, and the characteristic diffusion length scales of the mobile sublattice, with no universal mechanism across materials. Although compositional engineering improves diffusion, it is unclear how spatial and temporal correlations govern ion transport. Here, we introduce a relaxation-matched framework that combines intermediate scattering functions with decorrelation-time-resolved van Hove analysis to probe lithium-ion dynamics in pristine (LiLaZrO), Ga-substituted (LiGaLaZrO), and high-entropy garnets (LiGaLaNdZrTiHfCeNbTaO). Despite increasing compositional complexity and dynamical heterogeneity, the spatial signatures of Li-ion motion remain invariant at their characteristic decorrelation times, with both local Li-jump and long-range collective displacements collapsing onto a common length scale. However, compositional engineering leads to accelerated decay of ion correlations that compresses the associated time scales while preserving transport geometry. High-entropy substitution amplifies this effect by destabilizing intermediate-range order and promoting a dynamically percolating Li network. This framework provides a general route to disentangle spatial and temporal contributions to transport, identifying time-scale renormalization of correlation decay as a unifying design principle for superionic conductors.
Phycocyanin 645 (PC645) is a closed-form light-harvesting complex found in the lumen of the photosynthetic membrane of cryptophyte algae. These peripheral antenna complexes contain bilin chromophores that absorb sunlight...Phycocyanin 645 (PC645) is a closed-form light-harvesting complex found in the lumen of the photosynthetic membrane of cryptophyte algae. These peripheral antenna complexes contain bilin chromophores that absorb sunlight and transfer excitation energy to the core antenna complexes embedded in the thylakoid membrane. The location of cryptophyte antenna complex on the luminal side of the membrane is unusual. During photosynthetic activity, the pH of the lumen drops, by up to two pH units. There is little known about how this pH-change affects the light-harvesting complexes. In this study, we report multiscale simulations using a computationally efficient density functional tight-binding framework to investigate the spectroscopy and excitation energy transfer in the PC645 complex. Complementary experiments were conducted using both steady-state and time-resolved spectroscopic measurements at low, neutral, and high pH values. Our study shows that (de)protonation of specific bilin pigments, namely, the mesobiliverdins (MBVs), modulates the excitation energies, excitonic couplings, and spectral densities. These changes cause excitation transfer rates to increase by up to a factor of two to three, leading to pH-dependent energy transfer pathways in the complex. Using this model, we calculated the pH-dependent fluorescence quantum yield of the system, obtaining quantitative agreement with the experimental results. These computational simulations, supported by experiments, identify MBVs as a more prominent excitation sink than previously realized, and that this role is tuned by pH.
The direct deconstruction of polyolefins into olefins without external hydrogen source represents an ideal route for polyolefin upcycling, but it remains challenging due to the apparent trade-off between substrate conver...The direct deconstruction of polyolefins into olefins without external hydrogen source represents an ideal route for polyolefin upcycling, but it remains challenging due to the apparent trade-off between substrate conversion and product selectivity. We report herein layered MEL zeolite with confined Ru species synthesized through a ligand-assisted hydrothermal route, namely Ru@MEL, as an efficient catalyst for the quantitative upcycling of polyethylene to liquid olefins. The optimized Ru@MEL catalyst achieves >99% polyethylene conversion with 92% selectivity toward C-C olefins at 270 °C within 4 h, surpassing all catalyst systems reported so far. Ru incorporation drives framework aluminum migration into the straight channels of MEL zeolite during crystallization, thereby promoting the spatial proximity of Ru species to Brønsted and Lewis acid sites toward efficient catalysis. Mechanism insights disclose a synergistic cycle involving key steps of Ru-mediated C-H activation, Brønsted acid-catalyzed β-scission, and Lewis acid-assisted hydrogen transfer. Ru@MEL catalyst exhibits high efficiency, good stability, and scalability in upcycling real-world plastic wastes, highlighting its potential for practical applications.
Photooxidation of organic is a promising approach to upgrade low-value feedstocks into value-added chemicals, yet its product uniformity faces a formidable challenge due to uncontrollable oxidation pathways and depths. H...Photooxidation of organic is a promising approach to upgrade low-value feedstocks into value-added chemicals, yet its product uniformity faces a formidable challenge due to uncontrollable oxidation pathways and depths. Here, we tune the Schottky's interface by a strong metal-support interaction (SMSI) that induces a reverse charge transfer from TiO to Au, resulting in the formation of electron-rich Au species and Au-O-Ti interfacial sites. Using glycerol (GLY) photooxidation as a model reaction, the oxidation product is nearly 100% formate (FA) with a production rate of 2.15 mmol g h, which is 21.6-fold higher than that of conventional Schottky's Au/TiO. The impressive performance can be ascribed to that the Au selectively activates GLY via C-H bond adsorption rather than the conventional O-H bond cleavage to generate ·CHOH intermediates, while O is activated at the Au-O-Ti interface for ·O generation. The spatially decoupled activations of GLY and O favor one-step C-C bond cleavage and oxygenation, thereby achieving high selectivity of FA product. Overall, this SMSI-induced reverse charge transfer strategy provides a potential approach to enhance product uniformity in biomass upgrading.
A central challenge in single-atom catalysis lies in the precise construction of structurally well-defined local coordination environments at isolated metal sites while retaining low coordination numbers. Here, we presen...A central challenge in single-atom catalysis lies in the precise construction of structurally well-defined local coordination environments at isolated metal sites while retaining low coordination numbers. Here, we present an edge-bonding strategy that confines isolated metal atoms to well-defined edge sites of covalent triazine frameworks, enabling deterministic construction of structurally defined low-coordination environments. With Ni as a model, this approach yields single-atom sites with a well-defined Ni-N-C coordination motif and allows precise control over their spatial distribution. The strategy is readily extendable to other metals, affording single-atom catalysts with structurally defined and highly accessible low-coordination environments. Such geometrically low-coordination sites optimize photogenerated carrier separation and transport while selectively stabilizing the key *OCHO intermediate in the CO reduction pathway, thereby directing the reaction toward HCOOH with 98.5% selectivity. This work establishes a principle for achieving low-coordination microenvironments at single-atom sites via macroscopic regulation of support structures, providing a rational strategy for single-atom catalyst design.
The heterogeneous interface region serves as a critical domain in lithium metal batteries, where electrons, ions, and chemical reactions interact, significantly affecting cycling reversibility. However, the ion transport...The heterogeneous interface region serves as a critical domain in lithium metal batteries, where electrons, ions, and chemical reactions interact, significantly affecting cycling reversibility. However, the ion transport mechanism of the solid electrolyte interphase (SEI) still lacks quantitative characterization. Using Li metal mixed inorganic compounds as a model system, we correlate and quantify the Li exchange rates of key SEI inorganic components by applying the saturation-recovery method and establishing a two-site chemical exchange model. We not only quantitatively reveal the interfacial ion exchange rate between lithium metal and its SEI via a selective nuclear magnetic resonance exchange spectroscopy (EXSY NMR) technique but also demonstrate a close connection between interfacial transport and lithium deposition morphology by a COMSOL simulation. Furthermore, through multiscale characterization including cross-polarization (CP) NMR and cryoelectron microscopy (cryo-EM), we elucidate the Li transport mechanisms within the actual SEI: LiO can facilitate rapid Li transport, whereas the Li transport of LiF is highly dependent on building an interface with LiO. On the basis of these new kinetic insights, we construct a LiS artificial SEI using atomic layer deposition (ALD), successfully achieving 99.5% Coulombic efficiency and promoting uniform and dense lithium deposition. Our findings provide valuable design principles for engineering efficient SEIs in future lithium metal batteries.
High-order pancake bonding arising from the overlap of multiple π-type orbitals in π-conjugated molecules is exceedingly rare. Recently reported cofacially stacked hexaazatrinaphthylene trianions ([HAN]) stabilized by te...High-order pancake bonding arising from the overlap of multiple π-type orbitals in π-conjugated molecules is exceedingly rare. Recently reported cofacially stacked hexaazatrinaphthylene trianions ([HAN]) stabilized by tetravalent actinides exhibit six-electron triple pancake bonds, but the presence of counterions hides the intrinsic nature of the bonding. Here, we designed a neutral HAN derivative via hydrogen coordination, 1,5,9-trihydro-1,4,5,8,9,12-hexaazatriphenylene (HATH), which features a quartet ground state with three π-type singly occupied molecular orbitals. The HATH monomer dimerizes both in - and -cofacial arrangements, with ultrashort intermolecular separation of 2.968 and 2.971 Å with substantial interaction energy of -158.6 and -135.1 kJ/mol, respectively. The stability of these dimers occurs primarily through orbital interactions, three electron-sharing π-orbitals between two HATH fragments. Electrostatic interactions and dispersion make smaller but significant bonding contributions to the overall stability. These neutral dimers exhibit a genuine triple pancake bond, providing new insight into the nature of high-order π-stacking interactions. These strong intermolecular interactions can be important in aggregate formation and crystal formation.
Constructing functional materials on cell surfaces offers a promising strategy to enhance cellular robustness and functionality; however, most existing approaches rely on static shells that are incompatible with the dyna...Constructing functional materials on cell surfaces offers a promising strategy to enhance cellular robustness and functionality; however, most existing approaches rely on static shells that are incompatible with the dynamic nature of biological interfaces. This mismatch imposes an inherent trade-off between sustained protection and cellular proliferation. Inspired by natural membranes that integrate covalently structured functional units within dynamic, noncovalent matrices, we developed a hydrogen-bonding-mediated, growth-coupled assembly strategy to engineer adaptive porous membranes on living cells. Nanosized hydrogen-bonded organic framework (HOF) particles act as dynamic reservoirs of building units that, together with multivalent interfacial interactions, promote surface enrichment, reorganization, and crystallization into continuous membranes. This dynamic assembly mechanism accommodates cellular proliferation while maintaining structural integrity, cytoprotection, and selective molecular transport. Furthermore, the adaptive membranes impart photoactivity that couples with cellular metabolism, allowing light-driven cofactor regeneration and boosting triterpenoid betulinic acid production by 4.8-fold in engineered yeast while maintaining stress tolerance. This study establishes a design principle for integrating adaptive functional artificial membranes with living cells.
Achieving the synergistic integration of emission regulation and reversible electronic-state switching in aggregation-induced emission (AIE) systems remains challenging, as it requires balancing restriction of intramolec...Achieving the synergistic integration of emission regulation and reversible electronic-state switching in aggregation-induced emission (AIE) systems remains challenging, as it requires balancing restriction of intramolecular motion (RIM) with spin delocalization. Here, we construct a class of arylboron-functionalized tetraphenylethylene-analog molecules and systematically elucidate an RIM-governed AIE mechanism via a rotor-locking strategy. Structure-property correlations reveal that rotor positioning decisively dictates conformational freedom and emission behavior, endowing the system with pronounced AIE activity and reversible mechano-/piezochromic responses. Upon electrochemical reduction, stable boron-olefin radicals are generated, exhibiting broadband absorption spanning the visible to the NIR-II region. Leveraging the reversible redox activity of the boron center, electrochemical switching between closed- and open-shell states is achieved, enabling electrochromic devices with high optical contrast and fast response. These systems are further extended to applications in smart displays, large-area smart windows, and light-adaptive electrochromic canopy system.
Indoles bearing a stereogenic center at the C4 position are key motifs in natural products and pharmaceuticals, yet their catalytic enantioselective synthesis remains a formidable challenge. Herein, we report an iridium-...Indoles bearing a stereogenic center at the C4 position are key motifs in natural products and pharmaceuticals, yet their catalytic enantioselective synthesis remains a formidable challenge. Herein, we report an iridium-catalyzed enantioselective C4-alkylation of indoles with α-olefins and styrenes. The reaction proceeds with exclusive C4 selectivity and excellent enantioselectivity across a broad range of substrates. The C3 ,-dibenzylamide directing group and the chiral spiro diphosphite ligand are essential for achieving high regio- and enantioselectivity. Density functional theory calculations elucidate the origins of regio- and enantioselectivity. This method provides a general atom- and step-economical route to chiral C4-alkylated indoles.
Memory is a central principle underlying adaptive behavior in biological systems and an important source of inspiration for the design of functional artificial materials. While memory effects have been widely realized in...Memory is a central principle underlying adaptive behavior in biological systems and an important source of inspiration for the design of functional artificial materials. While memory effects have been widely realized in macroscopic materials and devices, whether comparable behavior can arise from dynamic molecular organization remains largely unexplored. In supramolecular polymers (SPs), memory has thus far been demonstrated primarily in the form of chiral memory, while other types of memory, such as structural memory─where supramolecular organization is retained despite changes at the molecular level─remain largely unexplored. Here, we demonstrate structural memory in SPs through light-driven control over self-assembly pathways. We introduce a photoswitchable dithienylethene-based molecular building block capable of reversible interconversion between open- and closed-ring isomers both in the monomeric and assembled state. Although both isomers undergo supramolecular polymerization into elongated one-dimensional fibers in methylcyclohexane, they differ markedly in their aggregation propensity and resulting morphology (rigid, bundled fibers for the open form vs flexible, individual fibers for the closed form). By controlling the sequence of photoirradiation and supramolecular polymerization, we obtain pathway-dependent supramolecular architectures that retain features of their formation history despite changes at the molecular level. These results establish a route toward SPs capable of storing pathway information and advance the design of history-dependent adaptive soft matter.
Optical-spin interfaces that enable the photoinitialization, coherent microwave manipulation, and optical readout of ground-state spins are promising for emerging quantum technologies. Molecular optical-spin interfaces o...Optical-spin interfaces that enable the photoinitialization, coherent microwave manipulation, and optical readout of ground-state spins are promising for emerging quantum technologies. Molecular optical-spin interfaces offer advantages over solid-state defects through synthetic control of their optical and spin properties. Optical initialization of these systems relies on spin-selective intersystem crossing between electronic states of different spin multiplicity. In this work, we demonstrate experimentally and theoretically that coherent excited-state evolutions enable optical spin polarization of luminescent tris(2,4,6-trichlorophenyl)methyl () monoradicals without the need for intersystem crossing. Inspired by the alignment-to-orientation conversion (AOC) phenomenon in atomic physics, we find that the doubly degenerate first excited state of -symmetric possesses a pseudo-orbital angular momentum that couples to the electron spin through in-state spin-orbit coupling, resulting in spin-dependent excited-state dynamics following photoexcitation. These coherent dynamics produce differential decay pathways to the ground state that generate persistent spin polarization in an applied magnetic field. Time-resolved electron paramagnetic resonance spectroscopy confirms photoinduced ground-state spin polarization in and its symmetry-preserving derivatives, while lower-symmetry analogues exhibit no polarization, consistent with a loss of pseudo-orbital angular momentum. These results establish a fundamentally new paradigm for optical spin initialization in organic radicals based on symmetry-enabled coherent dynamics and lay the foundation for establishing optical-spin interfaces in organic monoradicals.
A molecular torsional spring was developed to demonstrate a new strategy for molecular energy storage. Protonation of an -pyridylsuccinimide rotor lowers the rotational barrier and shifts the equilibrium toward the highe...A molecular torsional spring was developed to demonstrate a new strategy for molecular energy storage. Protonation of an -pyridylsuccinimide rotor lowers the rotational barrier and shifts the equilibrium toward the higher-energy -atropisomer. Neutralization kinetically traps this high-energy state, which is stable at room temperature for years. On heating, the stored energy is released and measured by DSC, as the atropisomer reverts to its equilibrium ratio. Since switching involves only single-bond rotation, the system avoids reactive intermediates and retains its performance over repeated energy storage-release cycles.