CCS ChemistryPub Date : 2026-04-10DOI: 10.31635/ccschem.026.202607388
Man Zhang, Simin Sun, Yujin Kim, Qiao-Wen Lin, Xin-Ru Hu, Peng Sun, Hoyeon Jang, Xingyu Lv, Liu-Yi Liu, Jong Seung Kim, Kang-Nan Wang
{"title":"Super-Resolution Imaging of Stress-Modulated Mitochondria-Lysosome Crosstalk in Ferroptosis","authors":"Man Zhang, Simin Sun, Yujin Kim, Qiao-Wen Lin, Xin-Ru Hu, Peng Sun, Hoyeon Jang, Xingyu Lv, Liu-Yi Liu, Jong Seung Kim, Kang-Nan Wang","doi":"10.31635/ccschem.026.202607388","DOIUrl":"https://doi.org/10.31635/ccschem.026.202607388","url":null,"abstract":"The mechanism by which mitochondria and lysosomes coordinate at mitochondria-lysosome contacts (MLCs), particularly during ferroptosis and energetic stress, remains unclear. Classic imaging logic, which uses two separate probes targeting mitochondria and lysosomes, is unsuitable for the precise analysis of MLCs owing to spectral crosstalk, differences in photostability, inconsistent retention, and asynchronous photobleaching. In this study, we designed a fluorescent probe, <b xmlns:bkstg=\"http://www.atypon.com/backstage-ns\" xmlns:fn=\"http://www.w3.org/2005/xpath-functions\" xmlns:pxje=\"java:com.atypon.frontend.services.impl.PassportXslJavaExtentions\" xmlns:urlutil=\"java:com.atypon.literatum.customization.UrlUtil\" xmlns:xlink=\"http://www.w3.org/1999/xlink\">\u0000<bold>SDML</bold></b>, that enables simultaneous, stable visualization of mitochondria and lysosomes with spectrally well-separated dual emissions. Integrating dual-fluorescence and dual-targeting capabilities into a single molecule, we addressed the aforementioned limitations and directly visualize the spatiotemporal dynamics of MLCs at a subcellular resolution, further revealing their stressmodulated remodeling. Under nutrient deprivation, <b xmlns:bkstg=\"http://www.atypon.com/backstage-ns\" xmlns:fn=\"http://www.w3.org/2005/xpath-functions\" xmlns:pxje=\"java:com.atypon.frontend.services.impl.PassportXslJavaExtentions\" xmlns:urlutil=\"java:com.atypon.literatum.customization.UrlUtil\" xmlns:xlink=\"http://www.w3.org/1999/xlink\">\u0000<bold>SDML</bold></b> imaging revealed that compounded energetic stress disrupts the adaptive coordination between mitochondria and lysosomes, impairing organelle interactions during ferroptosis. This disruption establishes a previously unrecognized link between autophagy and ferroptosis via organelle crosstalk. Our study proposed a powerful tool for analyzing mitochondria-lysosome dynamics and provides insights into the impact of MLCs on cell fate under energetic stress.","PeriodicalId":9810,"journal":{"name":"CCS Chemistry","volume":"124 1","pages":""},"PeriodicalIF":11.2,"publicationDate":"2026-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147641695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Singlet Photosensitizer for Superoxide Radical Mediated Photodynamic Therapy","authors":"Yongkang Yue, Xiaoting Jia, Xiaoni Zhao, Fangjun Huo, Ruibing Wang, Caixia Yin","doi":"10.31635/ccschem.026.202506921","DOIUrl":"https://doi.org/10.31635/ccschem.026.202506921","url":null,"abstract":"Photodynamic therapy (PDT) hinges on three pivotal components: light, triplet photosensitizers and molecular oxygen. Yet, the modulation of triplet states within photosensitizers is inherently challenging, constrained by the spin selection rules that limit universal regulation through chemical modification. Moreover, the pervasive hypoxic conditions within tumor tissues critically impede singlet oxygen generation. To transcend these barriers, we developed a singlet state-based photosensitization strategy with the production of superoxide anion radicals. Briefly, pyridinium as an acceptor was used to capture the excited state electron of the dye to form a charge-separated state radical, remarkably prolonging the lifetime of the excited states to ensure electron transfer from charge-separated state radical to molecular oxygen. The photosensitization mechanism predicated on the singlet excited state of the photosensitizer and circumvented the stringent reliance on molecular oxygen, similar to the traditional Type-I photosensitizers, within the tumor microenvironment. We denominated it as the Type-0 photosensitizer. Through comprehensive theoretical and experimental validation, we substantiated the viability of this photosensitization process and its feasibility for cancer PDT <i>in vivo</i>.","PeriodicalId":9810,"journal":{"name":"CCS Chemistry","volume":"32 1","pages":""},"PeriodicalIF":11.2,"publicationDate":"2026-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147641697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Helical Linker as a Conformational Editor: Differential Locking of AIEgens for Tailored Luminescence and Circularly Polarized Light","authors":"Jing Li, Xubin Wang, Jiahai Chen, Zhouyu Chen, Simin Lin, Rong Miao, Yu Fang","doi":"10.31635/ccschem.026.202607606","DOIUrl":"https://doi.org/10.31635/ccschem.026.202607606","url":null,"abstract":"The rational design of organic molecular dimers is pivotal for controlling photophysical properties, yet precise conformational regulation remains challenging. Here, a rigid and chiral [5]helicene spacer was introduced as a conformational editor to construct dimers (HTPE and HTPA) bearing tetraphenylethylene (TPE) or triphenylamine (TPA) units. The helicene linker effectively restricts intramolecular motion, leading to remarkable fluorescence enhancement in solution (47-fold for HTPE and 154-fold for HTPA). Notably, the helicene-imposed spatial confinement controls dimer symmetry, locking bulky TPE units into distinct conformations while enforcing identical conformations in the smaller TPA units. Furthermore, the fixed TPE conformations enable HTPE polymorphs with tunable fluorescence and strong circularly polarized luminescence (<i>g</i><sub>lum</sub> > 10<sup>−2</sup>). This work establishes helicenes as versatile conformational editors for the precise modulation of fluorescence and chiroptical properties in multichromophoric systems.","PeriodicalId":9810,"journal":{"name":"CCS Chemistry","volume":"20 1","pages":""},"PeriodicalIF":11.2,"publicationDate":"2026-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147631239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
CCS ChemistryPub Date : 2026-04-07DOI: 10.31635/ccschem.026.202607611
Ting-Jia Sun, Hu-Chong Wang, Qing Gu, Yuan-Jun Gao, Shu-Li You
{"title":"Asymmetric Dearomatization of Naphthols with Vinyl Aziridines and Vinyl Epoxide via Iridium-Catalyzed Allylic Etherification/Claisen Rearrangement","authors":"Ting-Jia Sun, Hu-Chong Wang, Qing Gu, Yuan-Jun Gao, Shu-Li You","doi":"10.31635/ccschem.026.202607611","DOIUrl":"https://doi.org/10.31635/ccschem.026.202607611","url":null,"abstract":"Transition-metal-catalyzed asymmetric allylic dearomatization of naphthols represents a robust strategy for constructing chiral naphthalenones. In this work, we have established an asymmetric allylic dearomatization reaction of naphthols employing racemic vinyl aziridines and vinyl epoxide as electrophilic reagents. Using iridium catalysts derived from chiral phosphorus ligands, the target <i>α</i>/<i>β</i>-naphthalenones containing an all-carbon quaternary chiral center are afforded in good yields with excellent chemo- and enantio-selectivities. The dearomatization reactions of naphthols with vinyl aziridines and vinyl epoxide proceed through an asymmetric allylic etherification/Claisen rearrangement pathway. The method exhibits broad functional group tolerance, and its compatibility with gram-scale reaction and versatile derivatization of the dearomatized products demonstrate its synthetic potentials. Computational studies suggest the dearomatized product is thermodynamically more stable than the corresponding allyl ether.","PeriodicalId":9810,"journal":{"name":"CCS Chemistry","volume":"64 1","pages":""},"PeriodicalIF":11.2,"publicationDate":"2026-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147631240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Divergent control of chirality and topology via transforming disperse achiral cages into homochiral 2D cage-MOFs","authors":"Suqiong Yan, Bo Yang, Shirong Ban, Yue Zhao, Yuan Zhang, Hui Ma, Fanda Feng, Wei Huang","doi":"10.31635/ccschem.026.202607662","DOIUrl":"https://doi.org/10.31635/ccschem.026.202607662","url":null,"abstract":"While chiral induction and spontaneous symmetry breaking are possibly generated by an achiral compound, it remains a great challenge to rationally predict and control the chirality of a self-assembly process. Herein, we report a chiral hierarchical self-assembly strategy to control and transfer the chirality information using dynamic Schiff-base covalent and coordination chemistry. Triphenylamine (TPA) atropisomers are used to form the prochiral [2+3] metal-cages (<b xmlns:bkstg=\"http://www.atypon.com/backstage-ns\" xmlns:fn=\"http://www.w3.org/2005/xpath-functions\" xmlns:pxje=\"java:com.atypon.frontend.services.impl.PassportXslJavaExtentions\" xmlns:urlutil=\"java:com.atypon.literatum.customization.UrlUtil\" xmlns:xlink=\"http://www.w3.org/1999/xlink\">\u0000<bold>Co-TPA</bold></b>, <b xmlns:bkstg=\"http://www.atypon.com/backstage-ns\" xmlns:fn=\"http://www.w3.org/2005/xpath-functions\" xmlns:pxje=\"java:com.atypon.frontend.services.impl.PassportXslJavaExtentions\" xmlns:urlutil=\"java:com.atypon.literatum.customization.UrlUtil\" xmlns:xlink=\"http://www.w3.org/1999/xlink\">\u0000<bold>Ni-TPA</bold></b>, and <b xmlns:bkstg=\"http://www.atypon.com/backstage-ns\" xmlns:fn=\"http://www.w3.org/2005/xpath-functions\" xmlns:pxje=\"java:com.atypon.frontend.services.impl.PassportXslJavaExtentions\" xmlns:urlutil=\"java:com.atypon.literatum.customization.UrlUtil\" xmlns:xlink=\"http://www.w3.org/1999/xlink\">\u0000<bold>Zn-TPA</bold></b>), which exhibit the <i>P</i> or <i>M</i> chiral conformation. Leveraging the coordination-directed enantioselectivity between the chiral auxiliary ligands and vacant metal sites, the remote stereochemistry information can be successfully transferred from chiral BNP to the TPA motif of metal-cage, facilitating optical activity and circularly polarized luminescence with red color. When the dialdehyde precursor was further modified by embedding a pyridyl unit as an additional coordination site, the disperse cages could be connected into one mesomeric <b xmlns:bkstg=\"http://www.atypon.com/backstage-ns\" xmlns:fn=\"http://www.w3.org/2005/xpath-functions\" xmlns:pxje=\"java:com.atypon.frontend.services.impl.PassportXslJavaExtentions\" xmlns:urlutil=\"java:com.atypon.literatum.customization.UrlUtil\" xmlns:xlink=\"http://www.w3.org/1999/xlink\">\u0000<bold>Cd-1D</bold></b> cage-MOF and a pair of enantiomeric <b xmlns:bkstg=\"http://www.atypon.com/backstage-ns\" xmlns:fn=\"http://www.w3.org/2005/xpath-functions\" xmlns:pxje=\"java:com.atypon.frontend.services.impl.PassportXslJavaExtentions\" xmlns:urlutil=\"java:com.atypon.literatum.customization.UrlUtil\" xmlns:xlink=\"http://www.w3.org/1999/xlink\">\u0000<bold>Zn-2D</bold></b> layered cage-MOFs through the chirality transfer pathways in different dimensions. Notably, spontaneous symmetry breaking and chiral self-sorting of conglomerate crystallization can be achieved for <b xmlns:bkstg=\"http://www.atypon.com/backstage-ns\" xmlns:fn=\"http://www.w3.org/2005/xpath-functions\" xmlns:pxje=\"java:com.atypon.frontend.services.impl.PassportXslJavaExtentions\"","PeriodicalId":9810,"journal":{"name":"CCS Chemistry","volume":"191 1","pages":""},"PeriodicalIF":11.2,"publicationDate":"2026-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147625490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Programmable Triplex DNAzyme Assembly for High-Fidelity Demethylase Imaging and Glutamine Metabolic Profiling in Live Cells","authors":"Yuqiu He, Xingxing Meng, Qingqing Zhang, Jinhua Shang, Xiaoqing Liu, Fuan Wang","doi":"10.31635/ccschem.026.202507057","DOIUrl":"https://doi.org/10.31635/ccschem.026.202507057","url":null,"abstract":"Accurate monitoring of nucleic acid-modifying enzymes, such as demethylases, is critical for understanding epigenetic regulation and cellular metabolism processes. DNAzymes have emerged as powerful tools for profiling demethylase activity but are seriously constrained by high background emerging from their noncatalytic signal transduction behaviors, and limited adaptability from their reliance on critical catalytic nucleobases. To address these challenges, we present a triplex DNA-integrated DNAzyme (TID) system in which the nonspecific background signal arising from uncontrollable DNAzyme-substrate binding is alleviated via the demethylase-programmable assembly of triplex DNA. Methyl groups in the triplex prevent premature DNAzyme-substrate binding and impair cofactor accommodation, thereby efficiently blocking DNAzyme catalysis and reducing the nonspecific background readout. Upon enzymatic demethylation, the DNAzyme restored its active conformation through triplex DNA assembly and then motivated the continuous cleavage of substrate reporters, achieving an ∼380% enhancement (from 6-fold to 29-fold) in the signal-to-background ratio compared with conventional DNAzymes. By integrating high-contrast demethylase imaging with cell-specific RNA guidance, the TID system achieved the in situ interpretation of glutamine metabolic fluctuations in live cells. With high fidelity and adaptability, this work provides a robust platform for detecting nucleic acid-modifying enzymes and holds immense potential for investigating these relevant pathological processes.","PeriodicalId":9810,"journal":{"name":"CCS Chemistry","volume":"64 1","pages":""},"PeriodicalIF":11.2,"publicationDate":"2026-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147617674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
CCS ChemistryPub Date : 2026-04-04DOI: 10.31635/ccschem.026.202507240
Xiaodong Chen, Wanqing Yu, Yijie Wu, Tianjing Zhang, Wenji Shao, Yi Tao, Zhaoyan Luo, Wenjie Yu, Hao Zhang, Xuhui Sun
{"title":"Ultralow-Loading Pt Nanosheets via In-Situ Electrochemical Reduction for High-Efficiency and Stable Hydrogen Evolution","authors":"Xiaodong Chen, Wanqing Yu, Yijie Wu, Tianjing Zhang, Wenji Shao, Yi Tao, Zhaoyan Luo, Wenjie Yu, Hao Zhang, Xuhui Sun","doi":"10.31635/ccschem.026.202507240","DOIUrl":"https://doi.org/10.31635/ccschem.026.202507240","url":null,"abstract":"The high cost and low availability of Pt-based electrocatalysts remain the primary bottlenecks for the large-scale implementation of proton exchange membrane electrolyzer cells in hydrogen production. Conventional synthesis methods struggle to simultaneously control catalyst dimensions and engineer active sites. Herein, we present a combined chemical-electrochemical strategy for synthesizing high-performance Pt catalysts featuring a low-dimensional morphology, ultralow loading and strain modulation via twin boundaries for hydrogen evolution reaction (HER). This approach involves chemical exfoliation to prepare ultrathin PtO<sub>x</sub> nanosheets, followed by in-situ electrochemical reduction under HER conditions. The resulting catalyst, with a Pt loading of approximately 0.1 wt %, achieves a low overpotential of 20 mV at 10 mA cm<sup>−2</sup> and exhibits exceptional mass activity, exceeding that of commercial Pt/C by more than 40-fold. The proton exchange membrane electrolyzer with a minimal cathodic loading of 2 μg<sub>Pt</sub> cm<sup>−2</sup> enables a current density of 1 A cm<sup>−2</sup> at 1.72 V and demonstrates remarkable durability for over 1000 h. Operando high-energy-resolution X-ray absorption near-edge structure experiments identify platinum hydride-like species as the true active sites, which are inferred to stabilize this unique structure against degradation. This work provides a general and effective pathway for designing efficient and durable electrocatalysts for sustainable hydrogen energy.","PeriodicalId":9810,"journal":{"name":"CCS Chemistry","volume":"16 1","pages":""},"PeriodicalIF":11.2,"publicationDate":"2026-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147617677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
CCS ChemistryPub Date : 2026-04-04DOI: 10.31635/ccschem.026.202507295
Pengjun Yuan, Yangyang Sun, Yifeng Chen, Miao Hong
{"title":"Sustainable All-Polythioester Thermoplastic Elastomers Enabled by Anionic Isomerization-Driven Ring-Opening Polymerization with Ultrastable Active Species","authors":"Pengjun Yuan, Yangyang Sun, Yifeng Chen, Miao Hong","doi":"10.31635/ccschem.026.202507295","DOIUrl":"https://doi.org/10.31635/ccschem.026.202507295","url":null,"abstract":"Aliphatic polythioesters have emerged as a new class of sustainable polymers, but their usages reported so far are limited to plastics. The synthesis of polythioesters with complex architectures for high-value applications is highly desirable but critically lacking, because the current catalysts generally fail to stabilize the active species at the end of polymerization or after complete monomer consumption. In this contribution, a simple and robust catalyst comprising CH<sub>3</sub>COSK/18-crown-6 was successfully constructed, which achieved the first living/controlled anionic isomerization-driven ring-opening polymerizations (IROPs) of five-membered thionolactones. The key to this achievement relied on the generation of ultrastable active species, able to effectively shut down side reactions during polymerizations and preserve their reactivity afterward for up to 30 days. Accordingly, the utilization of CH<sub>3</sub>COSK/18-crown-6 catalyst allowed unprecedented access to new sustainable all-polythioester thermoplastic elastomers, which possessed useful material performance and mechanical properties comparable with those of representative commercial polyolefin elastomer and olefin block copolymer.","PeriodicalId":9810,"journal":{"name":"CCS Chemistry","volume":"15 1","pages":""},"PeriodicalIF":11.2,"publicationDate":"2026-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147617678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Site-Isolated Heterogeneous Catalysts for CO2 Selective Conversion","authors":"Yu Zhang, Zijian Wang, Qing Xie, Rui Zhang, Shuyan Song, Hongjie Zhang, Xiao Wang","doi":"10.31635/ccschem.026.202507066","DOIUrl":"https://doi.org/10.31635/ccschem.026.202507066","url":null,"abstract":"Growing global energy demand and environmental concerns have intensified the focus on CO<sub>2</sub> utilization. Catalytic CO<sub>2</sub> conversion represents one of the most promising pathways for carbon transformation, enabling the efficient utilization of carbon resources and the production of high-value-added products. Despite significant progress, the precise molecular-level design of catalysts remains a challenge. Recently, site-isolated catalysts (SICs), a class of supported catalysts with spatially separated active centers, have attracted significant attention. SICs represent an advanced evolution beyond single-atom and nanocluster/nanoparticle catalysts, achieved by precisely constructing multiple active sites with tunable spacing and configuration. Their key advantage lies in the tailored coupling of active centers, which optimizes reaction pathways and kinetics through well-defined intersite interactions, such as synergistic effects between neighboring sites or directional enhancement of a primary active site. Moreover, the architecture of SICs allows parallel activation of reactants at isolated sites, circumventing the competitive adsorption limitations in single-site catalysts, while tandem catalysis facilitates the efficient synthesis of higher-value products. This review comprehensively summarizes recent advances in SICs for catalytic CO<sub>2</sub> conversion, discusses current challenges, and outlines future perspectives, aiming to provide a valuable reference and inspire new ideas in this rapidly evolving field.","PeriodicalId":9810,"journal":{"name":"CCS Chemistry","volume":"4 1","pages":""},"PeriodicalIF":11.2,"publicationDate":"2026-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147617675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
CCS ChemistryPub Date : 2026-04-04DOI: 10.31635/ccschem.026.202507177
Hui Wang, Yingjie Zhao
{"title":"Single-Crystal-to-Single-Crystal Polymerization and Photomechanical Motion in a Metal-Free Molecular Crystal","authors":"Hui Wang, Yingjie Zhao","doi":"10.31635/ccschem.026.202507177","DOIUrl":"https://doi.org/10.31635/ccschem.026.202507177","url":null,"abstract":"Photomechanical molecular crystals provide a powerful platform to correlate molecular-scale photochemistry with macroscopic mechanical responses. Although single-crystal-to-single-crystal (SCSC) photopolymerizations in metal-free organic crystal systems have been extensively reported, achieving SCSC photopolymerization with long-range covalent bond formation, structural integrity, and pronounced mechanical response remains challenging due to lattice strain accumulation and crystal instability. Here, we report a photoreactive molecule that forms two polymorphs with distinct solid-state reactivities. One undergoes an SCSC monomer-to-dimer conversion, while the other exhibits an SCSC monomer-to-polymer transformation accompanied by strong photomechanical motion. Notably, even after mechanical fragmentation, the resulting crystal fragments still retain single-crystal integrity, enabling full structural determination of both monomer and polymer. Fluorescence microscopy and crystallographic analysis show that polymerization initiates at crystal edges and propagates anisotropically inward, generating asymmetric lattice distortion and internal strain that drive macroscopic motion. In contrast, the dimer-forming polymorph shows no photomechanical response, highlighting the decisive role of crystal packing. This study elucidates the molecular origins of photomechanical effects and demonstrates a metal-free, light-induced monomer-to-polymer SCSC transformation that proceeds with preserved crystallinity while generating pronounced photomechanical behavior.","PeriodicalId":9810,"journal":{"name":"CCS Chemistry","volume":"122 1","pages":""},"PeriodicalIF":11.2,"publicationDate":"2026-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147617676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}