Lijie Liu

BN-isosteric acenes offer new opportunities for structural and property modulation, but the synthesis and conformational control of highly fused BN acenes remain challenging. Here we develop a photochemical strategy to convert BN heterocyclic precursors into highly fused BN acenes. By varying substituent positions and ring-fusion orientations, we achieve a conformational evolution from planar to double-helical structures. Despite pronounced backbone distortion, the six-membered BN rings retain substantial local aromaticity. Conformational modulation gives rise to diverse photophysical properties, including long-lived phosphorescence and persistent afterglow. Enhanced air stability arises from the synergistic effects of steric shielding of the boron centres by the double-helical architecture and HOMO energy lowering upon π-extension. This work establishes a new route to highly fused BN acenes and provides opportunities for tuning their three-dimensional structures and properties.

A library of 2D-3D aromatic o -carborane functionalized indolo/pyrrolo[1,2-a]quinoxalines with good AIE effect and 30–94% yields were constructed by a one-pot tandem (4+2) cyclization-oxidation reaction.

Lanthanide nitrides remain rare, being restricted to the singular example with a CeN(Li₂)Ce core stabilized by two Lewis acidic lithium ions. Here, we introduce a new cyclohexyltriamide ligand [Tach^DMBS] to lanthanide chemistry, which enables us to isolate a lanthanide nitride complex [{(Tach^DMBS)Ce}₂(μ-N)][Na(12-crown-4)₂] (6) with a linear CeNCe core without any alkali metal interaction. Complex 6 was prepared by the reaction of a rare dinuclear tuck-in-tuck-over cerium(IV) metallacycle [{(CH₂CHNSiMe₂^tBu)₂(CHNSiMe^tBu(μ-CH₂)Ce}₂] (4) with one equivalent of NaNH₂ in benzene in the presence of two equivalents of 12-crown-4, yielding 48%. The Ce-N(nitride) bond distances in 6 (2.051(19) Å) are close to the shortest Ce-N bonds reported so far, and a linear Ce-N-Ce bond angle in 6 (180.00°) is disclosed. The isostructural oxo analogue [{(Tach^DMBS)Ce}₂(μ-O)] (7) was prepared for comparison. Computational analysis of 6 and 7 reveals Ce═N multiple-bonding character consisting of two 2c-2e σ-bonds and two orthogonal 3c-2e π-bonds in 6, showing a similar bonding trend to that in the known CeN(Li₂)Ce linkage, but single bonds for Ce-O in 7, confirming the stronger donating capability of N^3- vs O^2- in the bridging mode and highlighting the importance of supporting ligands in stabilizing the unsupported CeNCe core.

Fungal diseases pose a growing threat to global food security, and natural product-derived fungicides remain a key green strategy. We synthesized 53 novel CF₃-containing luotonin A derivatives and evaluated them against four phytopathogenic fungi. Most compounds displayed strong in vitro activity against Gaeumannomyces graminis var. tritici (Ggt), and several were also effective against Rhizoctonia solani, Botrytis cinerea, and Curvularia lunata. Compound 18 exhibited the highest potency, with an EC₅₀ of 13.6 μg/mL against Ggt, 1.6-fold more active than silthiopham (21.2 μg/mL) and 18.8-fold more active than luotonin A (256 μg/mL). Electron microscopy analysis revealed that compound 18 severely disrupted Ggt mycelial morphology and induced ROS accumulation. Molecular docking, DFT, and ESP calculations provided insights into electron distribution and charge transfer, helping to elucidate its structural characteristics and antifungal mechanisms. These results offer a solid theoretical foundation for discovering natural product-based antifungal agrochemical candidates.

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.

The pursuit of high solid-state fluorescence quantum yields (Φ) in o-carborane systems and the understanding of their luminescent mechanisms have long been sought targets but are constrained by a strong focus on carbon-vertex modification that relies on disubstitution to circumvent aggregation-caused quenching. This work challenges the convention by demonstrating that B9 boron-vertex monosubstitution, when coupled with a rational alkynyl-bridge conjugation, can achieve exceptional performance. We report two key synthetic breakthroughs that enable scalable and selective B9 functionalization, yielding the novel derivative B9-TriPE-yn-o-CB. This compound exhibits a high solid-state Φ of 83.5%─a value that is about 7.5-fold higher than other monosubstituted comparisons and surpasses most carbon-disubstituted analogues. We have employed UV-vis absorption spectroscopy, solution fluorescence emission spectroscopy at 77 K, solid-state fluorescence emission spectroscopy, single-crystal X-ray diffraction, and DFT calculations to explore the luminescent mechanisms and found that the insertion of an alkynyl bridge enhances the conjugation between TriPE and o-CB. Single-crystal X-ray diffraction reveals a critical shortening of the cage C-C bond (1.612 Å) and concerted B-B bond contractions, providing direct structural evidence for the suppression of nonradiative decay. DFT calculations corroborate efficient 3D (boron cage)-2D (chromophore) electron delocalization, in which π-electrons are conveyed into the o-CB cage via the alkynyl bridge in both ground and excited states. Our findings not only challenge the requirement for carbon-vertex disubstitution but also establish a 3D-2D conjugation design principle for activating the B9 boron vertex, thereby opening new avenues for high-performance boron cluster emitters.

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 TPE-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.

Room temperature phosphorescent (RTP) molecules, owing to their unique afterglow characteristics, can translate microscopic electronic transitions into macroscopic smart responses, and have gradually emerged as a research hotspot in the field of smart molecules. Benefiting from the renewability, biocompatibility, and structural tunability of cellulose, these materials provide an ideal and sustainable platform for constructing RTP systems. Significant progress has been made in this field, leading to the emergence of numerous cellulose‐based RTP material systems with novel structures and excellent performance. This review summarizes recent advances in RTP systems cellulose derivatives. First, it elucidates the underlying mechanisms of cluster‐triggered emission, followed by a detailed discussion of four key construction strategies: regulation of aggregation structures, reconstruction of clustered emission centers, hydroxyl functionalization, and host‐guest doping. In addition, innovative applications in information security and environmental monitoring are highlighted. Finally, current challenges are discussed, and perspectives on the rational design of future biomass‐based RTP materials are provided.

Herein, quinazolinone-based TICT-type AIEgens were developed, converting ACQ to AIE. They exhibit strong blue emission, long phosphorescence lifetimes, and lipid-activated response, enabling high-resolution multilevel fingerprint imaging.