Chemical Science最新文献_第10页

Bifunctional Additive-Driven Shape Transitions of Block Copolymer Particles through Synergistic Quaternization and Protonation

IF 8.4 1区化学

Chemical Science Pub Date : 2025-03-08 DOI: 10.1039/d5sc00259a

Zhengping Tan, Soohyun Ban, Younghyeon Ahn, Kang Hee Ku, Bumjoon Kim

{"title":"Bifunctional Additive-Driven Shape Transitions of Block Copolymer Particles through Synergistic Quaternization and Protonation","authors":"Zhengping Tan, Soohyun Ban, Younghyeon Ahn, Kang Hee Ku, Bumjoon Kim","doi":"10.1039/d5sc00259a","DOIUrl":"https://doi.org/10.1039/d5sc00259a","url":null,"abstract":"Block copolymer (BCP) particles with tailored shapes and nanostructures hold promise for applications in cell adhesion, photonic system, and energy storage due to their unique optical and rheological properties. Conventional approaches relying on surfactant-mediated self-assembly often limit particle geometries to simple structures. Herein, we present a versatile approach to expand the morphology of poly(styrene-block-2-vinylpyridine) (PS-b-P2VP) BCP particles through the incorporation of 9-bromononanoic acid (BNA), a bifunctional additive that facilitates synergistic quaternization and protonation. Increasing the BNA-to-2VP molar ratio enhances P2VP hydrophilicity and reduces the pH value, driving dramatic shape transitions from onion-like spheres to tulip bulbs, ellipsoids, discs, and Janus cups. This morphological diversity is attributed to synergetic interfacial instability-driven water infiltration and pH-induced repulsion of protonated P2VP chains. Additives with a single functional group, however, yield limited morphologies, such as tulip bulbs or onion-like spheres. Notably, Janus cups fabricated via this strategy exhibit selective cargo-loading capabilities, highlighting the importance of precise control over the internal composition and structure of BCP particles.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"91 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143575219","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}

引用次数: 0

Mechanism and dynamics of photoswitchable flavoprotein charge-transfer complexes

IF 8.4 1区化学

Chemical Science Pub Date : 2025-03-07 DOI: 10.1039/d4sc08614g

Bo Zhuang, Guangliu Ran, Wenkai Zhang, Feng Gai

{"title":"Mechanism and dynamics of photoswitchable flavoprotein charge-transfer complexes","authors":"Bo Zhuang, Guangliu Ran, Wenkai Zhang, Feng Gai","doi":"10.1039/d4sc08614g","DOIUrl":"https://doi.org/10.1039/d4sc08614g","url":null,"abstract":"Because of their diverse uses in biological science and engineering, continued effort has been made to expand the pool of photoswitchable protein systems. A recent study demonstrated that in monomeric sarcosine oxidase (MSOX), photoexcitation of a charge-transfer (CT) complex formed by a flavin cofactor and a nonreactive ligand (e.g., methylthioacetate) induces the ligand to reversibly change conformation, with implications for the development of flavin-dependent fast photochromic proteins. However, the factors that control the underlying switching mechanism and dynamics remain largely unexplored. Herein, combining extensive protein mutagenesis, ultrafast laser spectroscopic measurements and classical and quantum computational approaches, we assess those factors in a range of protein variants, including those of MSOX and another flavoenzyme, N-methyltryptophan oxidase (MTOX), where we find that a similar photoswitching cycle can occur. We demonstrate that (1) the kinetic behaviors of the photoswitching cycle are protein- and ligand-dependent; (2) the photoswitching and backward thermal recovery rates can be tuned by mutation of a specific active-site residue (Met245 and Thr239 in MSOX and MTOX, respectively), with recovery rates spanning over an order of magnitude, and (3) modifications of the protein environment alter the conformational energy landscape of the ligand–flavin complex, consequently regulating the photocycle. Taken together, these findings highlight the versatility of such photoswitchable systems, providing a molecular basis for fine-tuning their photophysical properties.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"10 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143589933","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}

引用次数: 0

Configurational control of low-symmetry heteroleptic metal–organic cages with asymmetric ligands

IF 8.4 1区化学

Chemical Science Pub Date : 2025-03-07 DOI: 10.1039/d4sc08647c

Hao Yu, Ziteng Guo, Jie Tang, Ningxu Han, Junjuan Shi, Meng Li, Houyu Zhang, Ming Wang

{"title":"Configurational control of low-symmetry heteroleptic metal–organic cages with asymmetric ligands","authors":"Hao Yu, Ziteng Guo, Jie Tang, Ningxu Han, Junjuan Shi, Meng Li, Houyu Zhang, Ming Wang","doi":"10.1039/d4sc08647c","DOIUrl":"https://doi.org/10.1039/d4sc08647c","url":null,"abstract":"Low-symmetry metal–organic cages (MOCs) can better mimic the structure of biological enzymes compared to high-symmetry MOCs, due to their unique internal cavities that resemble the specialized and irregular active sites of enzymes. In this study, two low-symmetry heteroleptic MOCs with six Pd(II) centers, Pd6LA6LB6 and Pd6LB6LC6, were successfully constructed by combining two strategies: asymmetric ligand assembly and multi-ligand co-assembly. Crystallographic characterization and analysis revealed that Pd6LA6LB6 is a mixture of potentially 16 isomers. Introducing a methyl group at the ortho position of the coordination site of ligand LC induced steric hindrance, driving Pd6LB6LC6 to undergo a structural transformation and selectively assemble into a single dominant configuration from 13 potential isomers. This work not only demonstrates the immense potential of integrating asymmetric ligand assembly with multi-ligand co-assembly strategies but also highlights the critical role of steric effects in guiding assembly pathways and achieving precise configurational control in low-symmetry MOCs.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"1 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143589919","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}

引用次数: 0

Recent advances in room-temperature synthesis of covalent organic frameworks.

IF 7.6 1区化学

Chemical Science Pub Date : 2025-03-07 DOI: 10.1039/d5sc00109a

Dongchuang Wu, Ning Gu, Junru Yao, Yang Cao, Lun Wang, Imran Shakir, Youyi Sun, Yuxi Xu

{"title":"Recent advances in room-temperature synthesis of covalent organic frameworks.","authors":"Dongchuang Wu, Ning Gu, Junru Yao, Yang Cao, Lun Wang, Imran Shakir, Youyi Sun, Yuxi Xu","doi":"10.1039/d5sc00109a","DOIUrl":"10.1039/d5sc00109a","url":null,"abstract":"Covalent organic frameworks (COFs) have become a promising class of highly-crystalline polymers with layered stacking structures, ordered porous channels, and highly-tailorable structures. To date, most COFs have been synthesized via high-temperature solvothermal methods, which require complicated optimization of factors including temperature, solvent ratio, catalyst, and reaction time. Additionally, solvothermal conditions with high temperature and high pressure restrict the facile and large-scale synthesis of COFs for practical applications. In addition, the insolubility and lack of processability of the COF powders obtained via solvothermal methods hinder their potential application in film-related fields. Energy-efficient and environmentally benign synthetic methods to resolve these problems are highly desired. In this review, we provide an overview of the recent progress in room-temperature synthetic strategies for constructing COF powders or COF films. We first discuss in situ characterization technologies for exploring the COF growth mechanism. Then, we present representative room-temperature synthesis methods for COFs, including solid-liquid interfacial synthesis, liquid-liquid interfacial synthesis, on-water surface synthesis, water-phase synthesis, electrosynthesis, sonochemical synthesis, single-solution phase synthesis, mechanochemical synthesis, high-energy ionizing radiation synthesis, and photochemical synthesis. Finally, perspectives on room-temperature synthesis are proposed in the areas of single-crystal domains, novel room-temperature reaction types, crystallization mechanism, the design of chemical structures and green synthesis.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":" ","pages":""},"PeriodicalIF":7.6,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11912503/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143656343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Redox Non-Innocent Bis-Silylene Aluminium Complexes with a Carborane Backbone

IF 8.4 1区化学

Chemical Science Pub Date : 2025-03-07 DOI: 10.1039/d5sc01104c

Matthias Driess, Artemis Mary Saddington, Shenglai Yao, Christian Lorent

{"title":"Redox Non-Innocent Bis-Silylene Aluminium Complexes with a Carborane Backbone","authors":"Matthias Driess, Artemis Mary Saddington, Shenglai Yao, Christian Lorent","doi":"10.1039/d5sc01104c","DOIUrl":"https://doi.org/10.1039/d5sc01104c","url":null,"abstract":"The redox non-innocent bis-silylenyl ortho-carborane ligands [SiII(CCcage)SiII] (CCcage = o-C2B10H10, SiII = ArC(NtBu)2Si; Ar = C6H5, p-tBuC6H4), with their particular chelating and electronic properties, have been employed for the synthesis of new donor-stabilized SiII→AlIII complexes that could act as precursors to low oxidation state aluminium complexes. Due to the redox non-innocence of the carborane backbone, aluminium(III) iodide complexes with three ligand oxidation states were characterized: neutral and radical anionic closo- as well as dianionic nido-C2B10 cores. Reduction at the aluminium center could also be enacted with potassium/napthalene leading to naphthalene derivatives {K[SiII(CCcage)SiII]Al(C10H8)} from [1+4] cycloaddition reaction, pointing to transient low oxidation state aluminium species as likely intermediates.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"53 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143575220","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}

引用次数: 0

Deep-blue phosphorescence from platinum(ii) bis(acetylide) complexes with sulfur-bridged dipyridyl ligands.

IF 7.6 1区化学

Chemical Science Pub Date : 2025-03-07 DOI: 10.1039/d4sc08205b

Ka-Ming Tong, Jessica Toigo, Michael O Wolf

{"title":"Deep-blue phosphorescence from platinum(ii) bis(acetylide) complexes with sulfur-bridged dipyridyl ligands.","authors":"Ka-Ming Tong, Jessica Toigo, Michael O Wolf","doi":"10.1039/d4sc08205b","DOIUrl":"10.1039/d4sc08205b","url":null,"abstract":"New approaches to prepare rarer emitters such as those that are deep-blue are needed to advance OLED technologies. Here, we demonstrate that a series of new platinum(ii) bis(acetylide) complexes [Pt(N-N)(C[triple bond, length as m-dash]CPh)2] containing sulfur-bridged dipyridyl ligands (N-N) with various sulfur oxidation states: sulfide (S), sulfoxide (SO) and sulfone (SO2) give access to variable emission colors from green to deep-blue. Spectroscopic, electrochemical and computational studies show that mixed character excited states have energies which are significantly influenced by the oxidation state of sulfur and the presence of substituents. The sulfide and sulfoxide complexes are non-emissive in the solution state, while the sulfone complexes display 3MLCT/3LLCT excited-state yellow phosphorescence. In PMMA films the sulfide and sulfoxide complexes show intense deep-blue phosphorescence and green phosphorescence for the sulfone complexes, with photoluminescence quantum yields ranging from 0.35-0.91. Here we demonstrate the capability of changing the photophysical properties of these metal emitters by varying the oxidation state of sulfur to achieve intense deep-blue and green emitters.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":" ","pages":""},"PeriodicalIF":7.6,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11886617/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143584940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Disentangling chemical pressure and superexchange effects in lanthanide-organic valence tautomerism

IF 8.4 1区化学

Chemical Science Pub Date : 2025-03-07 DOI: 10.1039/d5sc01246e

Anton Viborg, Maja A Dunstan, Nathan J. Yutronkie, Amit Chanda, Felix Trier, Nini Pryds, Fabrice Wilhelm, Andrei Rogalev, Dawid Pinkowicz, Kasper Steen Pedersen

{"title":"Disentangling chemical pressure and superexchange effects in lanthanide-organic valence tautomerism","authors":"Anton Viborg, Maja A Dunstan, Nathan J. Yutronkie, Amit Chanda, Felix Trier, Nini Pryds, Fabrice Wilhelm, Andrei Rogalev, Dawid Pinkowicz, Kasper Steen Pedersen","doi":"10.1039/d5sc01246e","DOIUrl":"https://doi.org/10.1039/d5sc01246e","url":null,"abstract":"Valence tautomerism in molecule-based f-block materials remains virtually elusive. As a result, the effects driving and controlling the valence conversion phenomenon are poorly understood. Herein, we unravel these fundamental factors by systematic chemical modification of a bona fide lanthanide coordination solid, SmI2(pyrazine)2(tetrahydrofuran), in which a complete, temperature-driven conversion between Sm(II) and Sm(III) occurs abruptly around 200 K. Solid solutions incorporating either divalent, diamagnetic metal ions or Sm(III) ions feature disparate behavior. Substitution with redox-inactive, divalent metal ions invariably leads to lower conversion temperatures and reduced cooperativity. In contrast, incorporation of redox-inactive Sm(III) ions leads to trapped pyrazine anion radicals in the ligand scaffold, shifting the valence tautomeric conversion phenomenon towards higher temperature with virtually no loss of cooperativity. These materials are rare examples of lanthanide-organic materials hosting mixed valency, herein in both the lanthanide and organic scaffold, affording switchable conductivity associated with the valence tautomeric conversion.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"39 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143570155","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}

引用次数: 0

Correction: Exploiting the inherent promiscuity of the acyl transferase of the stambomycin polyketide synthase for the mutasynthesis of analogues

IF 7.6 1区化学

Chemical Science Pub Date : 2025-03-07 DOI: 10.1039/D5SC90046H

Li Su, Yaouba Souaibou, Laurence Hôtel, Christophe Jacob, Peter Grün, Yan-Ni Shi, Alicia Chateau, Sophie Pinel, Helge B. Bode, Bertrand Aigle and Kira J. Weissman

引用次数: 0

Fluoride-induced redox-switchable behaviour of a palladium (II)/(IV) couple

IF 8.4 1区化学

Chemical Science Pub Date : 2025-03-07 DOI: 10.1039/d4sc08203f

Sebastian Martinez Vivas, Macarena Poyatos, Eduardo Peris

{"title":"Fluoride-induced redox-switchable behaviour of a palladium (II)/(IV) couple","authors":"Sebastian Martinez Vivas, Macarena Poyatos, Eduardo Peris","doi":"10.1039/d4sc08203f","DOIUrl":"https://doi.org/10.1039/d4sc08203f","url":null,"abstract":"We report the preparation of two Pd(II) complexes based on (CCC)-pincer-NHC (NHC = N-heterocyclic carbene) ligands. One of these complexes features an NDI unit (NDI = naphthalene-diimide) attached to the CCC-pincer ligand. Reacting these complexes with bromine results in the formation of the corresponding palladium(IV) complexes, [PdBr3(NDI-CCC)] and [PdBr3(CCC)]. The NDI-containing pincer complex, (CCC)-pincer-NDI, exhibits a strong sensitivity to fluoride ions, which can induce a one-electron reduction of the naphthalene-diimide moiety. We demonstrate that the addition of fluoride induces the reduction of the NDI moiety via de formation of hydroxide anions, which are the effective reducing agents of the process. The addition of fluoride significantly affects the reactivity of the NDI-containing palladium complexes. For example, the palladium(IV) complex [PdBr3(NDI-CCC)] can transfer bromide to styrene in a stoichiometric manner, but this reaction is inhibited in the presence of fluoride. Similarly, the palladium(II) complex [PdI(NDI-CCC)] catalyzes the oxidative homocoupling of arylpyridines, but its catalytic activity is quenched when excess fluoride is added. Notably, we demonstrate that this process can be deactivated and reactivated by sequentially introducing an excess of fluoride and NOBF4, revealing a rare instance of a redox-switchable process within a Pd(II)/Pd(IV) catalytic cycle. In contrast, the (CCC)-pincer palladium(II) and (IV) complexes lacking the NDI unit show no sensitivity to fluoride. Our study demonstrates that a simple reagent, such as the fluoride anion, can effectively modulate the reactivity of the Pd(II)/Pd(IV) pair. More broadly, it shows that fluoride serves as a simpler alternative to the metal-based reducing agents commonly used in redox-switchable catalysis.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"29 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143570156","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}

引用次数: 0

Cooperativity in the assembly of H-bonded duplexes of synthetic recognition-encoded melamine oligomers

IF 8.4 1区化学

Chemical Science Pub Date : 2025-03-07 DOI: 10.1039/d4sc08591d

Mohit Dhiman, Luis Escobar, Joseph T. Smith, Christopher A. Hunter

{"title":"Cooperativity in the assembly of H-bonded duplexes of synthetic recognition-encoded melamine oligomers","authors":"Mohit Dhiman, Luis Escobar, Joseph T. Smith, Christopher A. Hunter","doi":"10.1039/d4sc08591d","DOIUrl":"https://doi.org/10.1039/d4sc08591d","url":null,"abstract":"Recognition-encoded melamine oligomers (REMO) are synthetic polymers composed of repeating triazine–piperazine units and equipped with phenol and phosphine oxide side-chains. Short oligomers have previously been shown to form length- and sequence-selective H-bonded duplexes in non-polar solvents. Here, automated solid phase synthesis was used to prepare homo-sequence REMO with either twelve phenol recognition units or twelve phosphine oxide recognition units. The ends of the oligomers were functionalised with an azide and an alkyne group to allow investigation of duplex formation by covalent trapping with copper-catalysed azide–alkyne cycloaddition (CuAAC) reactions. The oligomers were also functionalised with a dansyl fluorophore or a dabcyl quencher dye to allow investigation of duplex formation by Förster resonance energy transfer (FRET). Covalent trapping showed that the duplex is the major species present in a 1 : 1 mixture of the phenol 12-mer and phosphine oxide 12-mer at micromolar concentrations in dichloromethane. FRET titration experiments showed that the association constant for duplex formation is greater than 108 M−1 in chloroform, and DMSO denaturation experiments showed that duplex formation is highly cooperative. The Hill coefficient for denaturation of the 12-mer duplex was 4.6, which is significantly higher than the value measured for the corresponding 6-mer duplex (1.9). This behaviour mirrors that observed for nucleic acid duplexes, where denaturation becomes increasingly cooperative as more base-pairs are added to the duplex.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"3 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143570158","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}

引用次数: 0