Journal of the American Chemical Society最新文献

Annulated 1,4-Disilabenzene-1,4-diide and Dihydrogen Splitting

IF 15 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2024-10-23 DOI: 10.1021/jacs.4c12127

Falk Ebeler, Yury V. Vishnevskiy, Beate Neumann, Hans-Georg Stammler, Dariusz W. Szczepanik, Rajendra S. Ghadwal

The isolation of silicon analogues of phenyl anions such as (C₆H₅)⁻ and (C₆H₄)^2– is challenging owing to their extremely high reactivity associated with their silylene character and weak C–Si π-interaction. Herein, we report the first annulated 1,4-disilabenzene-1,4-diide compound [(ADC)Si]₂ (5) based on anionic dicarbene (ADC) scaffolds (ADC = PhC{N(Dipp)C}₂; Dipp = 2,6-iPr₂C₆H₃) as a green-yellow crystalline solid. Compound 5 is prepared by KC₈ reduction of the Si(IV) chloride [(ADC)SiCl₃]₂ (3) or the cyclic bis-chlorosilylene [(ADC)SiCl]₂ (4), which are also prepared for the first time. 5 is a neutral molecule, and each of the two-coordinated Si(I) atoms has a lone pair and an unpaired electron. Experimental and theoretical data indicate delocalization of the silicon unpaired electrons, resulting in a 6π-electron C₄Si₂ ring in 5. The diradical character (y) for 5 amounts to 15%. At room temperature, 5 readily reacts with dihydrogen (H₂) to form the elusive bis-hydridosilylenes [(ADC)SiH]₂ (Z)-6 and (E)-6. The [4 + 2]-cycloaddition of 5 and PhC≡CPh in yielding the barrelene-type bis-silylene [(ADC)SiCPh]₂ (7) emphasizes the diradical reactivity of 5. With elemental sulfur, 5 results in the S₂- and S₃-bridged silathione derivatives [(ADC)Si(S)]₂(μ-S₂) (8a) and [(ADC)Si(S)]₂(μ-S₃) (8b). Moreover, the treatment of 5 with Fe₂(CO)₉ affords the Fe(0) complex [(ADC)Si(Fe(CO)₄)]₂(μ-CO) (9), in which each silicon atom serves as a two-electron σ-donor ligand and shares one electron with the bridging CO unit to form two Si–C bonds. The molecular structures of all compounds have been established by X-ray diffraction, and representative compounds have been analyzed by quantum chemical calculations.

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引用次数: 0

Long-Lived Charge Carrier Photogeneration in a Cooperative Supramolecular Double-Cable Polymer 合作型超分子双缆聚合物中的长寿命电荷载流子光生成

IF 15 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2024-10-22 DOI: 10.1021/jacs.4c09637

Jan Joseph, José Augusto Berrocal, Nicolás M. Casellas, Dirk M. Guldi, Tomás Torres, Miguel García-Iglesias

A newly designed C₃-symmetric disc-shaped chromophore, BTT(NDI)₃, features electron accepting naphthalene diimides linked to an electron donor BTT core. BTT(NDI)₃ self-assembles in apolar solvents into highly ordered, chiral supramolecular fibers through π–π and 3-fold hydrogen-bonding interactions. This leads to a cooperative formation of plane-to-plane stacking of BTTs and J-aggregation of the outer NDIs. Such a structure ensures high charge mobility. Only photoexcitation of BTT in the BTT(NDI)₃ polymers triggers a unidirectional electron transfer from BTT to NDI and results in (BTT^•+-NDI^•–) lifetimes that are by up to 3 orders of magnitude longer compared to (NDI^•+-NDI^•–) that is formed upon NDI photoexcitation. A multiphasic decay implies ambipolar pathways for charge carriers, that is, electron and hole delocalization along the respective BTT and NDI stacks. Our supramolecular approach offers potential for developing functional supramolecular polymers with continuous pathways for electrons and holes and, in turn, minimizing charge recombination losses in organic photovoltaic devices.

一种新设计的 C3 对称圆盘形发色团 BTT(NDI)3，具有与电子供体 BTT 核心相连的电子受体萘二亚胺。BTT(NDI)3 在无极性溶剂中通过 π-π 和 3 倍氢键相互作用自组装成高度有序的手性超分子纤维。这导致 BTT 平面到平面堆叠和外层 NDI 的 J- 聚集的协同形成。这种结构确保了高电荷迁移率。只有光激发 BTT(NDI)3 聚合物中的 BTT 才会引发从 BTT 到 NDI 的单向电子转移，从而导致 (BTT-+-NDI--) 寿命比 NDI 光激发时形成的 (NDI-+-NDI--) 寿命长达 3 个数量级。多相衰变意味着电荷载流子的两极通路，即电子和空穴沿着各自的 BTT 和 NDI 叠层脱ocal。我们的超分子方法为开发具有电子和空穴连续通路的功能性超分子聚合物提供了潜力，进而可将有机光伏设备中的电荷重组损耗降至最低。

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引用次数: 0

Overcoming the Limitation of Ionomers on Mass Transport and Pt Activity to Achieve High-Performing Membrane Electrode Assembly 克服离子聚合物对质量传输和铂活性的限制，实现高性能膜电极组装

IF 15 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2024-10-22 DOI: 10.1021/jacs.4c10742

Fadong Chen, Lin Guo, Daojun Long, Shijian Luo, Yang Song, Meng Wang, Li Li, Siguo Chen, Zidong Wei

The membrane electrode assembly (MEA) is one of the critical components in proton exchange membrane fuel cells (PEMFCs). However, the conventional MEA cathode with a covered-type catalyst/ionomer interfacial structure severely limits oxygen transport efficiency and Pt activity, hardly achieving the theoretical performance upper bound of PEMFCs. Here, we design a noncovered catalyst/ionomer interfacial structure with low proton transport resistance and high oxygen transport efficiency in the cathode catalyst layer (CL). This noncovered interfacial structure employs the ionomer cross-linked carbon particles as long-range and fast proton transport channels and prevents the ionomer from directly covering the Pt/C catalyst surface in the CL, freeing the oxygen diffusion process from passing through the dense ionomer covering layer to the Pt surface. Moreover, the structure improves oxygen transport within the pores of the CL and achieves more than 20% lower pressure-independent oxygen transport resistance compared to the covered-type structure. Fuel-cell diagnostics demonstrate that the noncovered catalyst/ionomer interfacial structure provides exceptional fuel-cell performance across the kinetic and mass transport-limited regions, with 77% and 67% higher peak power density than the covered-type interfacial structure under 0 kPa_gauge of oxygen and air conditions, respectively. This alternative interfacial structure provides a new direction for optimizing the electrode structure and improving mass-transport paths of MEA.

膜电极组件（MEA）是质子交换膜燃料电池（PEMFC）的关键部件之一。然而，传统的 MEA 阴极采用覆盖型催化剂/离子体界面结构，严重限制了氧的传输效率和铂的活性，难以达到 PEMFC 的理论性能上限。在此，我们设计了一种非覆盖型催化剂/离子体界面结构，该结构的阴极催化剂层（CL）具有较低的质子传输阻力和较高的氧传输效率。这种非覆盖界面结构利用离子交联碳颗粒作为远距离快速质子传输通道，防止离子直接覆盖 CL 中的 Pt/C 催化剂表面，从而使氧气扩散过程免于通过致密的离子覆盖层到达 Pt 表面。此外，该结构还改善了 CL 孔隙内的氧气传输，与覆盖型结构相比，与压力无关的氧气传输阻力降低了 20% 以上。燃料电池诊断结果表明，非覆盖型催化剂/离子体界面结构在动力学和质量传输受限区域提供了卓越的燃料电池性能，在 0 kPagauge 氧气和空气条件下，峰值功率密度分别比覆盖型界面结构高 77% 和 67%。这种替代性界面结构为优化 MEA 的电极结构和改善质量传输路径提供了新的方向。

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引用次数: 0

cis-Dihydroxylation by Synthetic Iron(III)-Peroxo Intermediates and Rieske Dioxygenases: Experimental and Theoretical Approaches Reveal the Key O-O Bond Activation Step.

IF 14.4 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2024-10-22 DOI: 10.1021/jacs.4c09354

Peng Wu, Wenjuan Zhu, Yanru Chen, Zikuan Wang, Akhilesh Kumar, Binju Wang, Wonwoo Nam

Dioxygen (O₂) activation by iron-containing enzymes and biomimetic compounds generates iron-oxygen intermediates, such as iron-superoxo, -peroxo, -hydroperoxo, and -oxo, that mediate oxidative reactions in biological and abiological systems. Among the iron-oxygen intermediates, iron(III)-peroxo species are less frequently implicated as active intermediates in oxidation reactions. In this study, we present the combined experimental and theoretical investigations on cis-dihydroxylation reactions mediated by synthetic mononuclear nonheme iron-peroxo intermediates, demonstrating the importance of supporting ligands and metal centers in activating the peroxo ligand toward the O-O bond homolysis for the cis-dihydroxylation reactions. We found a significant ring size effect of the TMC ligand in [Fe^III(O₂)(n-TMC)]⁺ (TMC = tetramethylated tetraazacycloalkane; n = 12, 13, and 14) on the cis-dihydroxylation reactivity order: [Fe^III(O₂)(12-TMC)]⁺ > [Fe^III(O₂)(13-TMC)]⁺ > [Fe^III(O₂)(14-TMC)]⁺. Additionally, we found that only [Fe^III(O₂)(n-TMC)]⁺, but not other metal-peroxo complexes such as [M^III(O₂)(n-TMC)]⁺ (M = Mn, Co, and Ni), is reactive for the cis-dihydroxylation of olefins. Using density functional theory (DFT) calculations, we revealed that electron transfer from the Fe d_xz orbital to the peroxo σ*(O-O) orbital facilitates the O-O bond homolysis, with the O-O bond cleavage barrier well correlated with the energy gap between the frontier molecular orbitals of d_xz and σ*(O-O). Further computational studies showed that the reactivity of the synthetic [Fe^III(O₂)(12-TMC)]⁺ complex is comparable to that of Rieske dioxygenases in cis-dihydroxylation, providing compelling evidence of the potential involvement of Fe(III)-peroxo species in Rieske dioxygenases. Thus, the present results significantly advance our understanding of the cis-dihydroxylation mechanisms by Rieske dioxygenases and synthetic nonheme iron-peroxo models.

{"title":"cis-Dihydroxylation by Synthetic Iron(III)-Peroxo Intermediates and Rieske Dioxygenases: Experimental and Theoretical Approaches Reveal the Key O-O Bond Activation Step.","authors":"Peng Wu, Wenjuan Zhu, Yanru Chen, Zikuan Wang, Akhilesh Kumar, Binju Wang, Wonwoo Nam","doi":"10.1021/jacs.4c09354","DOIUrl":"https://doi.org/10.1021/jacs.4c09354","url":null,"abstract":"Dioxygen (O2) activation by iron-containing enzymes and biomimetic compounds generates iron-oxygen intermediates, such as iron-superoxo, -peroxo, -hydroperoxo, and -oxo, that mediate oxidative reactions in biological and abiological systems. Among the iron-oxygen intermediates, iron(III)-peroxo species are less frequently implicated as active intermediates in oxidation reactions. In this study, we present the combined experimental and theoretical investigations on cis-dihydroxylation reactions mediated by synthetic mononuclear nonheme iron-peroxo intermediates, demonstrating the importance of supporting ligands and metal centers in activating the peroxo ligand toward the O-O bond homolysis for the cis-dihydroxylation reactions. We found a significant ring size effect of the TMC ligand in [FeIII(O2)(n-TMC)]+ (TMC = tetramethylated tetraazacycloalkane; n = 12, 13, and 14) on the cis-dihydroxylation reactivity order: [FeIII(O2)(12-TMC)]+ > [FeIII(O2)(13-TMC)]+ > [FeIII(O2)(14-TMC)]+. Additionally, we found that only [FeIII(O2)(n-TMC)]+, but not other metal-peroxo complexes such as [MIII(O2)(n-TMC)]+ (M = Mn, Co, and Ni), is reactive for the cis-dihydroxylation of olefins. Using density functional theory (DFT) calculations, we revealed that electron transfer from the Fe dxz orbital to the peroxo σ*(O-O) orbital facilitates the O-O bond homolysis, with the O-O bond cleavage barrier well correlated with the energy gap between the frontier molecular orbitals of dxz and σ*(O-O). Further computational studies showed that the reactivity of the synthetic [FeIII(O2)(12-TMC)]+ complex is comparable to that of Rieske dioxygenases in cis-dihydroxylation, providing compelling evidence of the potential involvement of Fe(III)-peroxo species in Rieske dioxygenases. Thus, the present results significantly advance our understanding of the cis-dihydroxylation mechanisms by Rieske dioxygenases and synthetic nonheme iron-peroxo models.","PeriodicalId":49,"journal":{"name":"Journal of the American Chemical Society","volume":null,"pages":null},"PeriodicalIF":14.4,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142453448","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

Retraction of "Solvent Polarity under Vibrational Strong Coupling".

IF 14.4 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2024-10-22 DOI: 10.1021/jacs.4c12901

Maciej Piejko, Bianca Patrahau, Kripa Joseph, Cyprien Muller, Eloïse Devaux, Thomas W Ebbesen, Joseph Moran

引用次数: 0

Oxygen Vacancy-Mediated Synthesis of Inter-Atomically Ordered Ultrafine Pt-Alloy Nanoparticles for Enhanced Fuel Cell Performance 氧空位介导的原子间有序超细铂合金纳米粒子合成用于增强燃料电池性能

IF 15 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2024-10-22 DOI: 10.1021/jacs.4c07185

Fantao Kong, Yifan Huang, Xu Yu, Min Li, Kunming Song, Qiuyun Guo, Xiangzhi Cui, Jianlin Shi

Pt-based intermetallics are expected to be the highly active catalysts for oxygen reduction reaction (ORR) in proton-exchange membrane fuel cells but still face great challenges in controllable synthesis of interatomically ordered and ultrafine intermetallic nanoparticles. Here, we propose an oxygen vacancy-mediated atomic diffusion strategy by mechanical alloying to reduce the energy barrier of the transition from interatomic disordering to ordering, and to resist interparticulate sintering via strong M–O–C bonding. This synthesis results in a nanosized core/shell structure featuring an interatomically ordered PtM core and a Pt shell of two to three atomic layers in thickness and can be extended to the multicomponent PtM (M = Co, FeCo, FeCoNi, FeCoNiGa) systems. The electron enrichment in the Pt outer shell induced by the compressive strain leads to the enhanced antibonding orbital occupation below the Fermi level and accelerated OH* desorption kinetics. The optimized PtCo–O/C-6 catalyst presents excellent ORR activity (mass activity = 1.28 A mg_Pt^–1 at 0.9 V_iR-free, peak power densities = 2.38/1.25 W cm^–2 in H₂–O₂/–air) and durability (∼1% activity loss in over 50 h in air condition) in fuel cells at a total Pt loading of 0.1 mg_Pt cm^–2. Furthermore, we establish a systematic correlation to elucidate the formation mechanisms of highly ordered intermetallic catalysts underlying oxygen vacancies. This study provides a general approach for the large-scale production of highly ordered and nanosized Pt-dispersed intermetallic catalysts.

铂基金属间化合物有望成为质子交换膜燃料电池中氧还原反应（ORR）的高活性催化剂，但在可控合成原子间有序的超细金属间纳米颗粒方面仍面临巨大挑战。在此，我们提出了一种通过机械合金化实现氧空位介导的原子扩散策略，以降低从原子间无序化到有序化转变的能障，并通过强 M-O-C 键抵制颗粒间烧结。这种合成方法产生了一种纳米级的核/壳结构，其特点是原子间有序的铂金属核和厚度为两到三个原子层的铂外壳，并可扩展到多组分铂金属（M = Co、FeCo、FeCoNi、FeCoNiGa）体系。压缩应变引起的铂外壳电子富集导致费米级以下的反键轨道占用增强，并加速了 OH* 解吸动力学。优化后的 PtCo-O/C-6 催化剂在燃料电池中具有优异的 ORR 活性（0.9 ViR-free 时的质量活性 = 1.28 A mgPt-1，H2-O2/-空气中的峰值功率密度 = 2.38/1.25 W cm-2）和耐久性（空气条件下超过 50 小时的活性损失为 1%），总铂负载量为 0.1 mgPt cm-2。此外，我们还建立了一个系统关联，以阐明高度有序的金属间催化剂中氧空位的形成机制。这项研究为大规模生产高度有序的纳米铂分散金属间催化剂提供了一种通用方法。

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引用次数: 0

Ultra-Narrowband Circularly Polarized Luminescence from Multiple 1,4-Azaborine-Embedded Helical Nanographenes. 多重 1,4-氮杂硼烷嵌入螺旋纳米石墨的超窄带圆极化发光。

IF 14.4 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2024-10-22 DOI: 10.1021/jacs.4c11404

Fangyuan Zhang, Vincenzo Brancaccio, Fridolin Saal, Upasana Deori, Krzysztof Radacki, Holger Braunschweig, Pachaiyappan Rajamalli, Prince Ravat

In this manuscript we present a strategy to achieve ultranarrowband circularly polarized luminescence (CPL) from multiple 1,4-azaborine-embedded helical nanographenes. The impact of number and position of boron and nitrogen atoms in the rigid core of the molecule on optical properties─including absorption and emission maxima, photoluminescence quantum yield, Stokes shift, excited singlet-triplet energy gap and full width at half-maximum (fwhm) for CPL and fluorescence─was investigated. The molecules reported here exhibits ultranarrowband fluorescence (fwhm 16-17.5 nm in toluene) and CPL (fwhm 18-19 nm in toluene). To the best of our knowledge, this is among the narrowest CPL for any organic molecule reported to date. Quantum chemical calculations, including computed CPL spectra involving vibronic contributions, provide valuable insights for future molecular design aimed at achieving narrowband CPL.

在这篇手稿中，我们介绍了一种实现多个 1,4- 氮杂硼烷嵌入螺旋纳米石墨烯超宽带圆偏振发光（CPL）的策略。研究了硼原子和氮原子在分子刚性核心中的数量和位置对光学特性的影响，包括吸收和发射最大值、光致发光量子产率、斯托克斯偏移、激发单三态能隙以及 CPL 和荧光的半最大全宽（fwhm）。本文报告的分子表现出超窄带荧光（在甲苯中的 fwhm 为 16-17.5 nm）和 CPL（在甲苯中的 fwhm 为 18-19 nm）。据我们所知，这是迄今所报道的有机分子中最窄的 CPL 之一。量子化学计算，包括涉及振动贡献的 CPL 光谱计算，为未来旨在实现窄带 CPL 的分子设计提供了宝贵的见解。

引用次数: 0

Photoresponsive Organic Cages─Computationally Inspired Discovery of Azobenzene-Derived Organic Cages 光致伸缩有机笼--受计算启发发现偶氮苯衍生有机笼

IF 15 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2024-10-22 DOI: 10.1021/jacs.4c10217

Michael C. Brand, Hamish G. Trowell, James T. Pegg, Jake L. Greenfield, Magdalena Odaybat, Marc A. Little, Peter R. Haycock, Gokay Avci, Nicola Rankin, Matthew J. Fuchter, Kim E. Jelfs, Andrew I. Cooper, Rebecca L. Greenaway

The incorporation of photoresponsive groups into porous materials is attractive as it offers potential advantages in controlling the pore size and selectivity to guest molecules. A combination of computational modeling and experiment resulted in the synthesis of two azobenzene-derived organic cages based on building blocks identified in a computational screen. Both cages incorporate three azobenzene moieties, and are therefore capable of 3-fold isomerization, using either ditopic or tetratopic aldehydes containing diazene functionality. The ditopic aldehyde forms a Tri²Di³ cage via a 6-fold imine condensation and the tritopic aldehyde forms a Tet³Di⁶ cage via a 12-fold imine condensation. The relative energies and corresponding intrinsic cavities of each isomeric state were computed, and the photoswitching behavior of both cages was studied by UV–Vis and ¹H NMR spectroscopy, including a detailed kinetic analysis of the thermal isomerization for each of the EEZ, EZZ and ZZZ metastable isomers of the Tet³Di⁶ cage. Both cages underwent photoisomerization, where a photostationary state of up to 77% of the cis-isomer and overall thermal half-life of 110 h was identified for the Tet³Di⁶ species. Overall, this work demonstrates the potential of computational modeling to inform the design of photoresponsive materials and highlights the contrasting effects on the photoswitching properties of the azobenzene moieties on incorporation into the different cage species.

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引用次数: 0

Efficient Aerial Water Harvesting with Self-Sensing Dynamic Janus Crystals

IF 15 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2024-10-22 DOI: 10.1021/jacs.4c11689

Linfeng Lan, Liang Li, Chenguang Wang, Panče Naumov, Hongyu Zhang

Water scarcity is one of the most pressing issues of contemporary societal development that requires innovative technologies where the material not only harvests water but also plays an active role in the process. Here, we demonstrate a highly efficient optical self-sensing approach to humidity capture from the air, where both humidity-harvesting and water-transduction functionalities are imparted on slender organic crystals by partial silanization via layer-by-layer hybridization. We report that due to the integration of the harvesting of aerial moisture and the collection of the condensed water, the ensuing Janus-type crystals capture humidity with the highest-to-date water collection efficiency of 15.96 ± 0.63 g cm^–2 h^–1. The water-collecting elements are also capable of delivering the water by reversible and periodic elastic deformation, and their high optical transparency allows real-time monitoring of the periodic fog collection process by deformational modulation of passively or actively transduced light that outcouples at the crystal-droplet interface. The results could inspire sophisticated approaches to humidity harvesting where optically transparent crystals combine fog capture with self-sensing capabilities for continuous and optimized operation to maximize the cost-gain balance of aerial fog capture.

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引用次数: 0

Interwoven Trimeric Cage-Catenanes with Topological Chirality 具有拓扑手性的交织三元笼-烯烷

IF 15 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2024-10-22 DOI: 10.1021/jacs.4c10104

Lihua Chen, Zhenghong Chen, Weihao Wang, Chenhao Chen, Yoshiaki Kuboi, Chi Zhang, Chenfei Li, Shaodong Zhang

Catenanes have gained increasing attention for their unique features such as topological chirality. To date, the majority of works have focused on catenanes comprising monocyclic rings. Due to the lack of efficient synthetic strategy, catenanes of multiannulated monomers remain scarce. Here, we report the one-pot synthesis of an interwoven trimeric cage-catenane in high yield by dynamic imine condensation between diamine linkers of suitable length and trialdehyde panels in stoichiometry. The formation of cage-catenane is driven by the efficient 6-fold π–π stacking of panels. The monomeric cage and trimeric cage-catenane are interconvertible with reversible imine chemistry, with the latter thermodynamically being more favored. Using a topology-based statistical model, we first reveal that the formation probability of the interwoven catenane surpasses that of its chain-like isomer by 20%. When this pure mathematical model is refined by taking into account the strong template effect provided by the π–π stacking of aromatic panels, it shows that the interwoven structure emerges as the dominant species, almost ruling out the formation of the latter. Although composed of achiral cage monomers, the topological chirality of the interwoven trimeric catenane is unraveled by chiral-high-performance liquid chromatography (HPLC) and circular dichroism (CD) spectroscopy, and single-crystal X-ray diffraction (XRD) analysis of the interwoven cage-catenane also reveals a pair of two topological enantiomers. Our probability analysis-aided rationale would provide a design rationale for guiding the efficient synthesis of topologically sophisticated structures.

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引用次数: 0