Journal of the American Chemical Society最新文献

{"title":"Mechanistic Insights into Molecular Copper Hydride Catalysis: the Kinetic Stability of CuH Monomers toward Aggregation is a Critical Parameter for Catalyst Performance","authors":"David E. Ryan, Jack T. Fuller, III, Evan A. Patrick, Jeremy D. Erickson, Amy L. Speelman, Timothy G. Carroll, Gregory K. Schenter, Bojana Ginovska, Simone Raugei, R. Morris Bullock, Ba L. Tran","doi":"10.1021/jacs.4c17955","DOIUrl":"https://doi.org/10.1021/jacs.4c17955","url":null,"abstract":"The activity of molecular copper hydride (CuH) complexes toward the selective insertion of unsaturated hydrocarbons under mild conditions has contributed significantly to versatile methodologies for upgrading these feedstocks. However, these catalysts are particularly susceptible to deleterious aggregation, leading to the depletion of active CuH species. Little is known about the mechanisms of CuH aggregation, how it influences overall catalyst performance, and how it can be controlled. We address these challenges with mechanistic studies on a model reaction of unactivated alkene hydroboration catalyzed by (IPr*CPh₃)CuH (LCuH). We report a comprehensive mechanistic investigation of this system, identifying an aggregation pathway that continuously depletes catalytically active LCuH to form inactive CuH clusters during turnover. Deactivation of LCuH is controlled primarily by the competition between the kinetics of the initial LCuH dimerization step and that of alkene insertion into LCuH. We therefore propose that a comprehensive understanding of CuH catalyst performance must account for the <i>kinetics</i> of the initial LCuH dimerization step, revising a previously explored <i>thermodynamic</i> understanding of CuH aggregation, where the concentration of active species is controlled by equilibria established between CuH clusters and monomers. With a series of (NHC)CuH congeners (NHC = <i>N</i>-heterocyclic carbene), we demonstrate that ostensibly minor structural modifications to the ligand peripheries can drastically affect the LCuH dimerization kinetics, while maintaining reactivity toward on-cycle alkene insertion. We employed a computational approach based on molecular dynamics simulations to provide an in-depth understanding of how specific structural ligand modifications can substantially increase the kinetic stability of monomeric CuH catalysts. Our combined experimental and computational studies suggest strategies for rational ligand design that can be broadly applied to molecular catalyst systems that are susceptible to deactivation via aggregation pathways.","PeriodicalId":49,"journal":{"name":"Journal of the American Chemical Society","volume":"10 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143745731","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":"Enzyme-Mimic Photoinitiated Flow-Polymerization with High Stereoselectivity under Mild Conditions","authors":"Yuhui Zhang, Shuai Pang, Jiangwei Fu, Xiang Li, Yinting MoZeng, Guandi He, Zhenyuan Fang, Wei Li, Daoling Peng, Xiqi Zhang, Lei Jiang","doi":"10.1021/jacs.5c00736","DOIUrl":"https://doi.org/10.1021/jacs.5c00736","url":null,"abstract":"Enzymatic reactions can achieve efficient flow-polymerization with specificity and high stereoselectivity. However, current enzyme-mimic polymerization systems cannot achieve high stereoregularity in flow reactions under mild conditions. This inefficient chain control may be due to the absence of a specific catalyst structure for the target monomer. This study reports a model of enzyme-mimic catalytic material for the polymerization of a specific monomer. In particular, the specific enzyme-mimic photoinitiated flow-polymerization of benzyl acrylate was realized at 22 °C using zinc porphyrin metal–organic framework (Zn-PMOF) membranes with one-dimensional nanochannels, achieving the efficient synthesis of highly heterotactic polymers. Under visible light irradiation, the zinc porphyrin core on the membrane surface could initiate polymerization, while copper porphyrin MOF with similar structures could not. The specific channel structure of the Zn-PMOF membrane provided space for stereochemical control. Control experiments, density functional theory simulations, and spectroscopic characterizations show that the combination of size effect and channel–monomer interactions realized higher monomer conversion and polymer stereoregularity in the flow reaction. Furthermore, the crystallinity, shear stress, and ionic conductivity of enzyme-mimic polymers were considerably better than those of bulk polymerization products. Thus, this study provides a method for enzyme-mimic polymerization with high stereoselectivity under mild conditions.","PeriodicalId":49,"journal":{"name":"Journal of the American Chemical Society","volume":"75 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143745770","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":"Redox Studies of the Scandium Metallocene (C5H2tBu3)2ScII Lead to a Terminal Side-On (N═N)2– Complex: [(C5H2tBu3)2ScIII(η2-N2)]−","authors":"Joshua D. Queen, Ahmadreza Rajabi, Joseph W. Ziller, Filipp Furche, William J. Evans","doi":"10.1021/jacs.5c00607","DOIUrl":"https://doi.org/10.1021/jacs.5c00607","url":null,"abstract":"Cyclic voltammetry measurements on the scandium(II) metallocene, Cp^ttt₂Sc^II (Cp^ttt = C₅H₂^tBu₃), reveal a −1.87 V vs Fc⁺/Fc event assigned to the [Cp^ttt₂Sc]^+/0 redox couple and a −3.09 V process assigned to the [Cp^ttt₂Sc]^0/– redox couple, which are consistent with subsequent chemical studies. Chemical oxidation of Cp^ttt₂Sc^II with AgBPh₄ gives the scandocenium cation salt [Cp^ttt₂Sc^III][BPh₄], <b>1</b>. The [Cp^ttt₂Sc^III]⁺ cation does not coordinate the [BPh₄]⁻ anion or THF solvent; however, one of the methyl groups of a <i>tert</i>-butyl substituent has a close interaction with the Sc(III) ion. Decomposition occurs in the presence of a [ⁿBu₄N][PF₆] supporting electrolyte, and chemical studies indicate that <b>1</b> reacts with the [PF₆]⁻ anion by fluoride abstraction to form Cp^ttt₂Sc^IIIF and PF₅. Chemical reduction of <b>1</b> to Cp^ttt₂Sc^II proceeds with Cp*₂Sm^II and Cp*₂Co^II (Cp* = C₅Me₅), which is consistent with the measured reduction potentials. Cp^ttt₂Sc^II was not observed to react with N₂; however, the treatment of Cp^ttt₂Sc^II with KC₈ and 18-crown-6 (crown) under N₂ forms the (N═N)^2– complex, Cp^ttt₂Sc^III(μ-η²:η²-N₂)K(crown), <b>2</b>. The reaction of Cp^ttt₂Sc^II with KC₈ in the presence of 2.2.2-cryptand (crypt) generates [K(crypt)][Cp^ttt₂Sc^III(η²-N₂)], <b>3</b>, which is the first isolable complex of any metal with a terminal side-on (N═N)^2– ligand. These Ln^IIA₂/M/N₂ reactions (M = alkali metal; (A)⁻ = anion) are the Ln(II)/Ln(I) analogs of the previously reported Ln(III)/Ln(II) reactions, Ln^IIIA₃/M/N₂, in which reduction of Ln(III) complexes generates Ln(II) reactivity to form (N═N)^2– complexes.","PeriodicalId":49,"journal":{"name":"Journal of the American Chemical Society","volume":"58 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143737060","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":"Criegee Intermediates Significantly Reduce Atmospheric (CF3)2CFCN","authors":"Haotian Jiang, Chaolu Xie, Yue Liu, Chunlei Xiao, Weiqing Zhang, Hongwei Li, Bo Long, Wenrui Dong, Donald G. Truhlar, Xueming Yang","doi":"10.1021/jacs.5c01737","DOIUrl":"https://doi.org/10.1021/jacs.5c01737","url":null,"abstract":"Sulfur hexafluoride (SF₆) is widely used for many industrial purposes due to its superior insulating properties; however, it is also a potent greenhouse gas with a high global warming potential (GWP) and an atmospheric lifetime of approximately 3,200 years. Here, we investigate heptafluoroisobutyronitrile ((CF₃)₂CFCN, also called C4-fluoronitrile or C4-FN) to help determine if it is a sustainable alternative to SF₆. We present experimental measurements and high-level quantum chemical calculations with a new computational strategy to elucidate the reaction kinetics between C4-FN and Criegee intermediates (CIs), specifically CH₂OO and <i>syn</i>-CH₃CHOO. By employing a new strategy to obtain CCSDT(Q)/CBS-level accuracy for a larger system than has previously been possible, combined with state-of-the-art kinetics methods, we obtain good agreement between theoretical and experimental rate constants. We find that the reactions between C4-FN and CIs are substantially faster than previously known degradation pathways, particularly the OH radical reaction. This shows the importance of incorporating additional reactive species into atmospheric chemistry models and climate impact assessments, paving the way for more effective climate change mitigation. Including the CI reactions in two possible scenarios gives a predicted atmospheric lifetime of C4-FN of 2–34.5 years, with a significant reduction in its global warming potential. This supports C4-FN’s potential as an environmentally friendly substitute for SF₆.","PeriodicalId":49,"journal":{"name":"Journal of the American Chemical Society","volume":"183 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143745407","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":"Minimally Protected and Stereoselective O-Glycosylation of Carboxylic Acid Allows Rapid Access to α-1-O- and 2-O-Acyl Glycosides","authors":"Bangxing Hao, Rongxia Li, Panpan Wang, Yingjie Wang, Xiaolong Li, Peifan Xu, Qian Zhang, Xinhao Zhu, Xiaojuan Zhang, Yugen Zhu","doi":"10.1021/jacs.5c01845","DOIUrl":"https://doi.org/10.1021/jacs.5c01845","url":null,"abstract":"We herein reported a catalytic, minimally protected, and highly α-stereoselective glycosylation protocol using carboxylic acid as an acceptor and glycosyl 8-alkynyl-1-naphthoate as a donor, enabling efficient access to unprotected α-1-<i>O</i>- and 2-<i>O</i>-acyl glycosides. This method demonstrates excellent functional compatibility and scope generality, allowing for the glycosylation of a wide range of complex carboxylic acids. Notably, we successfully synthesized two natural products, α-penta-<i>O</i>-galloyl-<span>d</span>-glucopyranose and nyctanthesin A, using this protocol. Mechanistic studies highlighted the crucial role of the 1-<i>O</i> ester functionality in ensuring chemoselectivity and the important contribution of the 2-<i>O</i> functionality in facilitating the reaction.","PeriodicalId":49,"journal":{"name":"Journal of the American Chemical Society","volume":"15 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143745408","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":"Nanoscale Grain Boundary-Weakened Ce–O Covalency and Surface Confinement Intrinsically Boosting Ceria Surface Oxygen Reactivity","authors":"Weixin Zhao, Wenyu Jia, Jun Zhou, Tianyu Zhai, Yuefeng Wu, Zohaib Rana, Peng Sun, Yimeng Liu, Shuyuan Zhou, Guolei Xiang, Xun Wang","doi":"10.1021/jacs.5c03536","DOIUrl":"https://doi.org/10.1021/jacs.5c03536","url":null,"abstract":"Promoting the reactivity of surface lattice oxygen atoms of oxide nanomaterials is critical for enhancing their catalytic performances in oxidation, hydrogenation, and electrocatalytic reactions; however, the fundamental electronic mechanisms governing this surface reactivity have long remained insufficiently understood. Here, we reveal the electronic mechanism of how the nanoscale grain boundary (GB) boosts the intrinsic surface reactivity of CeO₂ nanomaterials, in which GBs are introduced by pyrolyzing the precursors of cerium carbonate and formate. The results of X-ray absorption near-edge structures (XANES) at the O K- and Ce L₃-edges reveal that GBs can reduce the degree of covalency of Ce–O bonds, while H₂-TPR and Raman spectra show that this decreased orbital overlap can further weaken the confinement strength of surface oxygen atoms by the lattice potential. This electronic effect can fundamentally boost the leaving activity of surface lattice oxygen atoms, which further promotes the formation of oxygen vacancies and the activation of the O₂ molecules to oxidize benzyl alcohol into benzaldehyde with 100% selectivity. This structure–function relationship based on reduction in lattice covalency provides a new electronic perspective to understand how GBs and size reduction enhance nanomaterial surface reactivity.","PeriodicalId":49,"journal":{"name":"Journal of the American Chemical Society","volume":"12 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143745748","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":"Bacillus subtilis Utilizes Decarboxylated S-Adenosylmethionine for the Biosynthesis of Tandem Aminopropylated Microcin C, a Potent Inhibitor of Bacterial Aspartyl-tRNA Synthetase","authors":"Alexey Kulikovsky, Eldar Yagmurov, Anastasiia Grigoreva, Aleksandr Popov, Konstantin Severinov, Satish K. Nair, Guy Lippens, Marina Serebryakova, Sergei Borukhov, Svetlana Dubiley","doi":"10.1021/jacs.4c18468","DOIUrl":"https://doi.org/10.1021/jacs.4c18468","url":null,"abstract":"The biosynthetic pathways of natural products involve unusual biochemical reactions catalyzed by unique enzymes. Aminopropylation, although apparently simple, is an extremely rare modification outside polyamine biosynthesis. The canonical pathway used in the biosynthesis of peptide-adenylate antibiotic microcin C of <i>E. coli</i> (<i>Eco</i>-McC) entails alkylation by the <i>S</i>-adenosyl-methionine-derived 3-amino-3-carboxypropyl group of the adenylate moiety and subsequent decarboxylation to yield the bioactive aminopropylated compound. Here, we report the structure and biosynthesis of a new member of the microcin C family of antibiotics, <i>Bsu</i>-McC, produced by <i>Bacillus subtilis</i> MG27, which employs an alternative aminopropylation pathway. Like <i>Eco</i>-McC, <i>Bsu</i>-McC consists of a peptide moiety that facilitates prodrug import into susceptible bacteria and a warhead, a nonhydrolyzable modified isoasparaginyl-adenylate, which, when released into the cytoplasm, binds aspartyl-tRNA synthetase (AspRS) inhibiting translation. In contrast to the <i>Eco</i>-McC, whose warhead carries a single aminopropyl group attached to the phosphate moiety of isoasparaginyl-adenylate, the warhead of <i>Bsu</i>-McC is decorated with a tandem of two aminopropyl groups. Our <i>in silico</i> docking of the <i>Bsu</i>-McC warhead to the AspRS-tRNA complex suggests that two aminopropyl groups form extended interactions with the enzyme and tRNA, stabilizing the enzyme–inhibitor complex. We show that tandem aminopropylation results in a 32-fold increase in the biological activity of peptidyl-adenylate. We also show that <i>B. subtilis</i> adopted an alternative pathway for aminopropylation in which two homologous 3-aminopropyltransferases utilize decarboxylated S-adenosylmethionine as a substrate. Additionally, <i>Bsu</i>-McC biosynthesis alters the social behavior of the <i>B. subtilis</i> producer strain, resulting in a sharp decrease in their ability to form biofilms.","PeriodicalId":49,"journal":{"name":"Journal of the American Chemical Society","volume":"183 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143737290","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":"Low-Temperature Direct Arylation Polymerization for the Sustainable Synthesis of a Library of Low-Defect Donor–Acceptor Conjugated Polymers via Pd/Ag Dual-Catalysis","authors":"Hwangseok Kim, Hyeonjin Yoo, Hongsik Kim, Jun-Mo Park, Byoung Hoon Lee, Tae-Lim Choi","doi":"10.1021/jacs.4c16831","DOIUrl":"https://doi.org/10.1021/jacs.4c16831","url":null,"abstract":"Donor–acceptor alternating conjugated polymers (D–A CPs) are one of the best materials for high-performance organic electronic devices, owing to their low bandgap and high charge carrier mobility. However, most of the D–A CPs are synthesized by less sustainable polymerization methods. To address this issue, direct arylation polymerization (DArP), eliminating the need for transmetalating agents, was developed over the past two decades. Nevertheless, C–H activation during DArP still requires significantly harsh reaction conditions, limiting the precision and applicability of CPs. In this report, we demonstrate a versatile and sustainable Pd/Ag dual-catalytic DArP conducted at low or even room temperatures, thereby yielding low-defect D–A CPs. Initially, electron-deficient acceptor substrates with various electronic properties and p<i>K</i>_a underwent successful concerted-metalation-deprotonation (CMD) via Ag catalysis with mild conditions and highly chemoselective Pd-catalyzed C–C coupling. This synergistic dual-catalysis allowed for the library synthesis of D–A and A–A CPs from acceptor C–H monomers and aryl halide monomers at low temperatures (25–70 °C) in sustainable solvents such as <i>p</i>-cymene. Interestingly, the D–A CPs obtained via Pd/Ag DArP displayed higher structural regularity and crystallinity, eventually outperforming those prepared by conventional synthetic methods in device performances of ambipolar organic field-effect transistors (μ_e up to 0.80 cm² V^–1 s^–1) and complementary metal-oxide semiconductor inverters (gain up to 102).","PeriodicalId":49,"journal":{"name":"Journal of the American Chemical Society","volume":"103 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143745406","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":"Reduction by Oxidation: Selective Hydrodehalogenation of Aryl Halides by Mediated Oxalate Oxidation","authors":"Joshua A. Beeler, Rune P. Walkingshaw, Safiya A.S. Hamud, Henry S. White","doi":"10.1021/jacs.5c01366","DOIUrl":"https://doi.org/10.1021/jacs.5c01366","url":null,"abstract":"Electro-organic reduction reactions are canonically carried out at a cathode at which a significant negative potential is applied. Specifically, at carbon electrodes, aryl bromides and chlorides undergo heterogeneous reduction in organic solvents at potentials more negative than −2 V vs <i>E</i>^0′ for the Fc/Fc⁺ couple (Fc = ferrocene). To decrease the overpotential for reduction reactions, homogeneous or heterogeneous electrocatalysis strategies are often employed. Here, we present an electrochemical method to reduce aryl bromides and chlorides that is initiated by an oxidation reaction at very mild potentials (∼0 V vs Fc/Fc⁺). Specifically, electrochemical oxidation of an outer-sphere redox mediator, 1,1-dimethylferrocene, in dry <i>N,N</i>-dimethylformamide (DMF) containing oxalate (C₂O₄^2–), results in the homogeneous one-electron oxidation of C₂O₄^2–. The resulting C₂O₄^•– decomposes in ∼1 μs to release the carbon dioxide radical anion (CO₂^•–), a potent reductant that is oxidized to CO₂ at –2.68 V vs Fc/Fc⁺. In this way, an oxidation reaction at low electrode potentials enables homogeneous reduction of aryl bromides and chlorides, which are otherwise directly reduced at very negative potentials. Using this method, selective hydrodehalogenations of electron-deficient aryl bromides and chlorides are carried out at a reticulated vitreous carbon anode with up to quantitative conversion yields. Cyclic voltammetry and finite difference simulations are used to characterize the hydrodehalogenation of 4-bromobenzonitrile via C₂O₄^2– oxidation. Additionally, we show that the efficiency of hydrodehalogenation is tuned by deliberate additions of water to DMF solutions, leading to a substantial improvement in overall conversion yields without interference from water or proton reduction.","PeriodicalId":49,"journal":{"name":"Journal of the American Chemical Society","volume":"103 5 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143737062","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":"3D Imaging Reveals Widespread Stacking Disorder in Single Crystal 2D Covalent Organic Frameworks","authors":"Priti Kharel, Patrick T. Carmichael, Anusree Natraj, Chloe E. Pelkowski, Sang hyun Bae, William R. Dichtel, Pinshane Y. Huang","doi":"10.1021/jacs.4c16207","DOIUrl":"https://doi.org/10.1021/jacs.4c16207","url":null,"abstract":"Although tailored porosity is a defining feature of layered, two-dimensional (2D) polymers known as 2D covalent organic frameworks (COFs), understanding the interplanar stacking of 2D COFs and their resulting three-dimensional (3D) pore structure remains challenging. Here, we use scanning transmission electron microscopy and ptychography, an emerging 3D angstrom-scale imaging method, to study single-crystalline particles of the imine-linked 2D COF TAPB-DMPDA. Previously assumed to adopt an average-eclipsed structure with only angstrom-level stacking disorder, we find the crystals contain widespread stacking disorder of larger magnitudes, including interplanar shifts up to a half unit cell and nanoscale inhomogeneities in stacking and tilt. 3D visualizations show pore channels are distorted by this stacking disorder. The extensive stacking disorder found in even high-quality 2D COFs has profound implications for envisioned applications and should motivate the development of design strategies to control their 3D structures.","PeriodicalId":49,"journal":{"name":"Journal of the American Chemical Society","volume":"36 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143737289","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}