Accounts of Chemical Research最新文献

{"title":"Challenge and Chance of Single Atom Catalysis: The Development and Application of the Single Atom Site Catalysts Toolbox","authors":"Xiao Liang,&nbsp;Shuangchao Yao,&nbsp;Zhi Li and Yadong Li*,&nbsp;","doi":"10.1021/acs.accounts.4c0085710.1021/acs.accounts.4c00857","DOIUrl":"https://doi.org/10.1021/acs.accounts.4c00857https://doi.org/10.1021/acs.accounts.4c00857","url":null,"abstract":"<p >Single atom catalysis has garnered widespread attention in the past decade. In general, single atom catalysis refers to a catalytic process involving the participation of single atom sites. A single atom site refers to an active site with only one metal atom playing the main role in the catalysis process. This metal atom is usually coordinated by other atoms in the active site and anchored on the support. Heterogeneous catalysts in which all active sites are single atom sites are referred to as single atom site catalysts (SASCs). Owing to their distinctive active site architecture, single atom catalysis has shown ultrahigh atomic utilization efficiency and unique catalytic activity and selectivity in many systems such as thermal catalysis, electrocatalysis, and environmental catalysis.</p><p >However, the preparation of SASCs poses significant challenges as metal species tend to sinter and agglomerate during high-temperature treatment. In the past decade, we have challenged the controllable preparation of SASCs based on more than ten years of experience in nanomaterial synthesis. Several representative SASC preparation strategies have been proposed by our group, such as pyrolysis of MOFs with metal ions doped in the skeleton, M@ZIF-8 with a metal precursor fixed by the host–guest interaction, and M/N-rich support precursors. Additionally, “top-down” strategies starting from metal nanoparticles have been established. Based on these synthetic strategies, a systematic SASCs toolbox has been successfully built.</p><p >In addition to the SASCs, we have expanded the toolbox to include the dual-atom-site catalysts (DASCs) (including active sites with dual active metal atoms or including dual kinds of single atom sites) and nanosingle-atom-site catalysts (NSASCs) (catalysts with both single atom sites and nanoparticle/cluster sites). With the help of a variety of “tools” in the toolbox, single atom catalysis has shown its application value in many important processes such as bulk chemical catalysis, fine chemical catalysis, energy catalysis, and environmental catalysis. Based on laboratory-scale research, we further explored the feasibility of single atom catalysis in industrial catalysis and successfully applied single atom catalysis to industrial-level automobile exhaust purification, which will soon achieve commercialization.</p><p >This Account provides a concise overview of the evolution of single atom catalysis, summarizes the preparation strategies for SASCs pioneered by our group over the past decade, and highlights the SASCs toolbox developed through these strategies. We also showcase the practical applications of the SASCs toolbox in key catalytic fields, highlight our progress in advancing the industrialization of single atom catalysis (particularly for automobile exhaust purification), and discuss the future prospects of single atom catalysis in industrial applications.</p>","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":"58 10","pages":"1607–1619 1607–1619"},"PeriodicalIF":16.4,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144088362","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":"Fundamental Principles in Catalysis from Mechanistic Studies of Oxidative Decarboxylative Coupling Reactions","authors":"Jessica M. Hoover*,&nbsp;","doi":"10.1021/acs.accounts.5c0014210.1021/acs.accounts.5c00142","DOIUrl":"https://doi.org/10.1021/acs.accounts.5c00142https://doi.org/10.1021/acs.accounts.5c00142","url":null,"abstract":"&lt;p &gt;Oxidative decarboxylative coupling (ODC) reactions have been recognized as powerful alternatives to traditional cross-coupling reactions due to the ability to generate (hetero)biaryl structures from simple and readily available carboxylic acid precursors. These reactions, however, are underdeveloped due to the requirement for &lt;i&gt;ortho&lt;/i&gt;-nitrobenzoate coupling partners and silver salts as oxidants. Our research program has focused on the development of new catalytic ODC reactions, as well as mechanistic studies of these reactions to uncover the origin of these synthetic limitations. As the framework for these studies, we explored two key ODC reactions developed in our group: (1) a Ni-catalyzed decarboxylative arylation reaction that relies on silver as the oxidant and (2) a Cu-catalyzed decarboxylative thiolation reaction capable of operating under aerobic conditions. Our findings, disclosed in this Account, have uncovered the importance of the &lt;i&gt;ortho&lt;/i&gt;-substituent and revealed that Ag-based oxidants are also responsible for mediating the decarboxylation and transmetalation steps.&lt;/p&gt;&lt;p &gt;Systematic exploration of the decarboxylation of a series of well-defined Ag-benzoate complexes allowed us to probe the importance of the &lt;i&gt;ortho&lt;/i&gt;-nitro group in the decarboxylation step. Kinetic measurements of a large series of differently substituted benzoates were found to correlate with the field effect (&lt;i&gt;F&lt;/i&gt;) of the &lt;i&gt;ortho&lt;/i&gt;-substituent, revealing this feature to be responsible for the enhanced reactivity of these favored benzoates.&lt;/p&gt;&lt;p &gt;Our studies of the Ni-catalyzed decarboxylative arylation reaction uncovered an unexpected redox transmetalation step in this system. Synthesis and isolation of the proposed nickelacycle and Ag-aryl intermediates enabled direct study of the fundamental coupling steps. Catalytic and stoichiometric reactions of these complexes, paired with DFT calculations, supported a redox transmetalation step in which the Ag-aryl intermediate transfers the aryl ligand from Ag&lt;sup&gt;I&lt;/sup&gt; to Ni&lt;sup&gt;II&lt;/sup&gt; with concomitant oxidation to generate a Ni&lt;sup&gt;III&lt;/sup&gt;-bis(aryl) intermediate.&lt;/p&gt;&lt;p &gt;Finally, detailed mechanistic studies of our Cu-catalyzed decarboxylative thiolation reaction demonstrated how this catalyst system is able to use O&lt;sub&gt;2&lt;/sub&gt; as the terminal oxidant. Kinetic studies paired with the synthesis and reactivity of well-defined copper intermediates revealed decarboxylation from a Cu&lt;sup&gt;I&lt;/sup&gt;-benzoate resting state, despite the oxidizing reaction conditions which could support higher oxidation state intermediates. We also identified the intermediacy of diphenyl disulfide (PhSSPh) formed from the thiophenol (PhSH) coupling partner under the aerobic Cu-catalyzed conditions. The reaction of PhSSPh with the catalyst proceeds via oxidative transfer of the PhS fragment to Cu&lt;sup&gt;I&lt;/sup&gt; that is analogous to that of the redox transmetalation observed in Ni-catalyzed decarboxylative arylation.&lt;/p&gt;&lt;p &gt;Th","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":"58 10","pages":"1670–1682 1670–1682"},"PeriodicalIF":16.4,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144088441","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":"Molecular Mechanisms of Virulence Regulation in Staphylococcus aureus: A Journey into Reconstitutive Biochemistry","authors":"Steven P. Bodine,&nbsp; and ,&nbsp;Tom W. Muir*,&nbsp;","doi":"10.1021/acs.accounts.5c0011710.1021/acs.accounts.5c00117","DOIUrl":"https://doi.org/10.1021/acs.accounts.5c00117https://doi.org/10.1021/acs.accounts.5c00117","url":null,"abstract":"&lt;p &gt;Methodological development in the fields of genetics, chemical biology, and biochemistry over the last several decades has provided researchers with a diverse set of powerful tools to investigate biological processes. Leveraging these innovations in concert, scientists can now characterize biological pathways at a level of complexity ranging from systems biology down to molecular and atomic detail.&lt;/p&gt;&lt;p &gt;Throughout this Account, we illustrate how discoveries made using these tools build on each other to develop a comprehensive understanding of biological pathways. Advancements in genetic sequencing facilitates association of genotypes and phenotypes, independent of biochemical mechanism. Through the biochemical reconstitution of the interactions between biological macromolecules─including the small molecules (ligands and metabolites) and proteins─that participate in these biological pathways, scientists can characterize the specific molecular features that link genotype and phenotype. This facilitates identification of targets within these pathways that can be manipulated to achieve a greater understanding of the biological process or to develop interventions to improve human health outcomes.&lt;/p&gt;&lt;p &gt;Specifically, we describe how this toolbox was leveraged to discover and characterize the molecular biochemistry underlying control of pathogenicity in the Gram-positive bacterium &lt;i&gt;Staphylococcus aureus&lt;/i&gt;. Concurrent with advancements in the investigative tools available to the scientific community, we and others reported on the genetic, molecular, and biochemical/biophysical components of this regulatory system. Virulence control in &lt;i&gt;S. aureus&lt;/i&gt; is achieved through a chemical system of bacterial cell-to-cell communication indexed to local population density, referred to as quorum sensing (QS). We and our collaborators identified that this QS system is encoded in the &lt;i&gt;a&lt;/i&gt;ccessory &lt;i&gt;g&lt;/i&gt;ene &lt;i&gt;r&lt;/i&gt;egulator (&lt;i&gt;agr&lt;/i&gt;) operon and functions via the biosynthesis, secretion, and accumulation of a short peptide signaling molecule─the autoinducing peptide (AIP)─in the local environment correlated with the growth of &lt;i&gt;S. aureus&lt;/i&gt; in the same biological niche. Above a threshold concentration, these AIPs bind and activate a cell-surface receptor to stimulate an intracellular response resulting in altered gene expression and bacterial group behaviors. We discovered that chemical modification of these AIPs often generates molecules that exhibit potent inhibition of &lt;i&gt;agr&lt;/i&gt; QS, with demonstrated therapeutic potential to treat &lt;i&gt;S. aureus&lt;/i&gt; infections. We went on to characterize the biochemical mechanism of signaling molecule biosynthesis and receptor activation in controlled systems through &lt;i&gt;in vitro&lt;/i&gt; reconstitution of the constituent enzymes and substrates. Biochemical reconstitution enabled quantitative assessment of biophysical parameters. These efforts culminated in the comprehensive characterization and functional &lt;i&gt;in vitr","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":"58 10","pages":"1657–1669 1657–1669"},"PeriodicalIF":16.4,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144088472","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":"Molecular Mechanisms of Virulence Regulation in Staphylococcus aureus: A Journey into Reconstitutive Biochemistry.","authors":"Steven P Bodine,Tom W Muir","doi":"10.1021/acs.accounts.5c00117","DOIUrl":"https://doi.org/10.1021/acs.accounts.5c00117","url":null,"abstract":"ConspectusMethodological development in the fields of genetics, chemical biology, and biochemistry over the last several decades has provided researchers with a diverse set of powerful tools to investigate biological processes. Leveraging these innovations in concert, scientists can now characterize biological pathways at a level of complexity ranging from systems biology down to molecular and atomic detail.Throughout this Account, we illustrate how discoveries made using these tools build on each other to develop a comprehensive understanding of biological pathways. Advancements in genetic sequencing facilitates association of genotypes and phenotypes, independent of biochemical mechanism. Through the biochemical reconstitution of the interactions between biological macromolecules─including the small molecules (ligands and metabolites) and proteins─that participate in these biological pathways, scientists can characterize the specific molecular features that link genotype and phenotype. This facilitates identification of targets within these pathways that can be manipulated to achieve a greater understanding of the biological process or to develop interventions to improve human health outcomes.Specifically, we describe how this toolbox was leveraged to discover and characterize the molecular biochemistry underlying control of pathogenicity in the Gram-positive bacterium Staphylococcus aureus. Concurrent with advancements in the investigative tools available to the scientific community, we and others reported on the genetic, molecular, and biochemical/biophysical components of this regulatory system. Virulence control in S. aureus is achieved through a chemical system of bacterial cell-to-cell communication indexed to local population density, referred to as quorum sensing (QS). We and our collaborators identified that this QS system is encoded in the accessory gene regulator (agr) operon and functions via the biosynthesis, secretion, and accumulation of a short peptide signaling molecule─the autoinducing peptide (AIP)─in the local environment correlated with the growth of S. aureus in the same biological niche. Above a threshold concentration, these AIPs bind and activate a cell-surface receptor to stimulate an intracellular response resulting in altered gene expression and bacterial group behaviors. We discovered that chemical modification of these AIPs often generates molecules that exhibit potent inhibition of agr QS, with demonstrated therapeutic potential to treat S. aureus infections. We went on to characterize the biochemical mechanism of signaling molecule biosynthesis and receptor activation in controlled systems through in vitro reconstitution of the constituent enzymes and substrates. Biochemical reconstitution enabled quantitative assessment of biophysical parameters. These efforts culminated in the comprehensive characterization and functional in vitro reconstitution of agr QS in a synthetic system in a minimal model at the interfac","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":"14 1","pages":""},"PeriodicalIF":18.3,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143915064","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":"Precise Synthesis of Dual-Atom Catalysts for Better Understanding the Enhanced Catalytic Performance and Synergistic Mechanism.","authors":"Di-Chang Zhong, Yu-Chen Wang, Mei Wang, Tong-Bu Lu","doi":"10.1021/acs.accounts.4c00855","DOIUrl":"https://doi.org/10.1021/acs.accounts.4c00855","url":null,"abstract":"<p><p>ConspectusDual-atom catalysts (DACs), featuring two catalytic sites in close proximity, have emerged as a new frontier in energy-related catalysis. Compared with single-atom catalysts (SACs), DACs have more space to optimize the catalytic performance by changing the dual-atom catalytic sites and their coordination environments. Through adjusting the compositions and coordination environments of the metal sites in DACs, it is possible to finely tune the electronic and geometric properties of active centers, and then the synergistic effects for facilitating substrates activation and intermediates stabilization can be strengthened or optimized, consequently tailoring diverse reaction pathways and achieving various challenging catalytic reactions. The most important yet challenging task in DACs studies is the precise synthesis of DACs, which is crucial to understand the relationship between the catalytic performance and structure at the atomic level. In most cases, DACs were synthesized via the pyrolysis of a mixture of metal salts and organic ligands, in which two metals are randomly distributed in DACs, and it was difficult to control the M···M distance (M = metal ion) and uniform dispersion of DACs. Hence, developing innovative strategies for the precise synthesis of DACs with definite structures and high-efficiency catalytic performance is urgently needed.In this Account, we tentatively summarize the strategies for the precise synthesis of DACs and their applications in activation and conversion of small molecules such as H₂O, CO₂, and so on. Focusing on the precise synthesis of DACs, three types of synthesis strategies have been put forward and systematically introduced. Based on the precise synthesis strategies, the applications of the resulting DACs with high purity in synergistically activating and converting small molecules have concurrently been discussed, including the cleavage of C-C bonds, activation and reduction of CO₂ and H₂O, and so on. Attempts have been made to explain why the catalytic performance of DACs for these functions is much higher than what SACs have achieved. Efforts have been made on revealing the influences of dual-metal site types, the separations between dual metals, their geometry configurations and coordination environments, as well as the ligand structures on the catalytic performance. Emphasis has been placed on the analysis of the structure-reactivity relationship and revealing the synergistic mechanism at the molecular level. Finally, perspectives on the current challenges and future development of DACs have been put forward. We anticipate and believe that this Account will provide profound insights into the synthesis of structurally defined DACs and give new insights of synergistic catalytic effects in DACs.</p>","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":"58 9","pages":"1379-1391"},"PeriodicalIF":16.4,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143950922","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":"Selective Transformation of Biomass and the Derivatives for Aryl Compounds and Hydrogen via Visible-Light-Induced Radicals.","authors":"Wen-Min Zhang, Wen-Ting Niu, Fang-Fang Tan, Yang Li","doi":"10.1021/acs.accounts.5c00038","DOIUrl":"10.1021/acs.accounts.5c00038","url":null,"abstract":"<p><p>ConspectusFor sustainable development, exploring renewable resources is an urgent priority. Nonfood biomass, one of the largest renewable resources on Earth, primarily comprises three key components: lignin (ca. 15-30%), cellulose (ca. 35-50%), and hemicellulose (ca. 20-30%). Theoretically, nonfood biomass can be converted into green chemicals and energy. However, most studies have focused on the generation of chemicals and carbon-based energy under harsh conditions, often resulting in lower selectivities. Therefore, further efforts to explore efficient and selective methods for producing chemicals and hydrogen (H₂) are essential to promoting the practical applications of renewable biomass. In this Account, we summarize our contributions to the efficient and selective transformation of biomass and its derivatives into aryl compounds and H₂. These transformations were achieved using visible-light-induced photocatalytic systems that generate active radicals to selectively cleave C-C, C-O, C-H, and O-H bonds under mild conditions, without using noble metals. First, aryl compound production was achieved by chemoselective cleavage of C-C and C-O bonds using aryl carboxyl radicals and aryl ether radical cations. Specifically, the aryl carboxyl radical in the charge-transfer complex induced the chemoselective cleavage of C-C bonds of aryl carboxylic acids, which are platform molecules derived from lignin oxidation; the aryl carboxyl radical in free form facilitated the chemoselective cleavage of C-O bonds in the model of the 4-O-5 lignin linkage. Moreover, arenols and aryl alcohols were obtained via cooperation of the aryl ether radical cation and the vanadate-induced chemoselective cleavage of the C-O bonds of the models of various lignin linkages. Second, we developed a streamlined strategy for H₂ production from biomass using a one-pot, two-step route with formic acid (HCO₂H) as an intermediate for H₂ storage by thermocatalysis. Using this strategy by photoredox catalysis, HCO₂H was initially obtained via the alkoxy radical-induced gradual cleavage of C-C bonds in cellulose, hemicellulose, glucose, and their derivatives. Subsequently, efficient H₂ production from biomass-based HCO₂H was realized via hydroxyl radical (·OH)-induced C-H and the following cleavage of the O-H bonds, with cooperation of the nickel catalysis. Third, the highest H₂ production capability from biomass was achieved via efficient water reforming. This process utilized alkoxy radicals followed by generated carbon cations via electrocatalysis, inducing a well-organized cleavage of C-C, O-H, and C-H bonds. We anticipate that these insights will inspire the development of more efficient, stable, and cost-effective catalytic systems, accelerating the utilization of biomass as a renewable resource and driving other related significant transformations.</p>","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":" ","pages":"1407-1423"},"PeriodicalIF":16.4,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143612749","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":"Side Chain Engineering toward Chemical Doping of Conjugated Polymers.","authors":"Ze-Fan Yao, Jie-Yu Wang, Jian Pei","doi":"10.1021/acs.accounts.5c00121","DOIUrl":"https://doi.org/10.1021/acs.accounts.5c00121","url":null,"abstract":"&lt;p&gt;&lt;p&gt;ConspectusSolution-processable conjugated polymers are typically composed of two distinct structural components: rigid conjugated backbones and flexible side chains, each with unique roles and properties. The conjugated backbone forms the core framework of the polymer and is directly responsible for its optoelectronic properties, such as light absorption, emission, and charge transport. Meanwhile, the conjugated backbone can undergo chemical doping, where molecular dopants introduce charge carriers to modulate the carrier density and electrical conductivity. Therefore, the conjugated backbone is the critical determinant of the resulting optoelectronic performance. However, on the other hand, the flexible side chains, originally introduced to improve solution processability, were long considered chemically inert to the doping reaction. Recent advances have shown that the role of side chains is more than just improving solubility, demonstrating the significant impact of side chains on the packing of the conjugated backbone, film morphology, and electronic properties of conjugated polymers. Side chain engineering has become an essential design strategy for creating high-performance conjugated polymers in various applications.In this Account, we aim to emphasize the importance of side chain engineering toward controllable chemical doping of conjugated polymers, where side chain engineering allows us to tune the molecular packing, doping efficiency, and film morphology, thereby enhancing charge transport and optoelectronic performance. Specifically, the length, branching structures, and functional groups of the side chains can be systematically varied to control the solubility, miscibility, and interactions of conjugated polymers with dopants. For example, longer or branched side chains can improve solubility but may disrupt the π-π stacking between the conjugated backbones, thereby reducing the charge transport efficiency of the polymer. Shorter or linear side chains may enhance backbone packing and electronic coupling, though at the expense of reduced solubility. The impact of side chains on the doping process is particularly noteworthy. Although side chains are chemically inert to doping reactions, their design influences all three critical steps of the doping process: mixing, ionization, and carrierization. Side chains affect the spatial distribution of dopants during mixing, modulate the local environment to facilitate charge transfer during ionization, and influence the dissociation of ion pairs into free charge carriers during carrier generation. Functional side chains with polar groups, for example, can enhance dopant-polymer compatibility, while those with functional groups can modulate the dielectric environment to weaken ion pairing and promote free carrier generation. The interplay between side chains and the conjugated backbone is critical to achieving optimal optoelectronic performance in applications such as organic photovoltaics,","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":"58 9","pages":"1496-1508"},"PeriodicalIF":16.4,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143950674","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":"Discovery of Crystalline Inorganic Solids in the Digital Age.","authors":"D Antypov, A Vasylenko, C M Collins, L M Daniels, G R Darling, M S Dyer, J B Claridge, M J Rosseinsky","doi":"10.1021/acs.accounts.4c00694","DOIUrl":"https://doi.org/10.1021/acs.accounts.4c00694","url":null,"abstract":"&lt;p&gt;&lt;p&gt;ConspectusThis Account considers how the discovery of crystalline inorganic materials, defined as their experimental realization in the laboratory, can benefit from computation: computational predictions afford candidates for laboratory exploration, not discoveries themselves. The discussion distinguishes between the novelty of a material in terms of its composition and in terms of its structure. The stepwise modification of the composition of a parent material with retention of its crystal structure can reduce the risk in seeking new materials and offers the ability to fine-tune properties which has demonstrated value in optimizing materials performance. However, the parent structures first need to be identified, thus emphasizing the importance of materials discovery beyond simple analogy as a key complementary activity. We describe a workflow we have developed to accelerate discovery of such new structures by addressing many of the challenges, in particular the identification of chemistries that are likely to afford materials and the targeting of reactions within their compositional spaces. Data on experimentally isolated phases are used to prioritise candidate chemistries with machine learning, and crystal structure prediction is used to target compositions within those chemistries for synthesis by computationally constructing probe structures whose energies are indicative of the accessible stability at a given composition. We show how this workflow usefully identifies the parts of chemical space offering new materials and has afforded new structures in practice. The discovery of the solid lithium electrolyte Li&lt;sub&gt;7&lt;/sub&gt;Si&lt;sub&gt;2&lt;/sub&gt;S&lt;sub&gt;7&lt;/sub&gt;I illustrates the role of the workflow in exploring design hypotheses constructed by synthesis researchers and the role of new materials in increasing understanding, in this case by expanding the design paths available for superionic transport. Substitution into Li&lt;sub&gt;7&lt;/sub&gt;Si&lt;sub&gt;2&lt;/sub&gt;S&lt;sub&gt;7&lt;/sub&gt;I affords a structurally related material with superior low temperature transport properties, emphasizing the role of new structures in enabling subsequent materials optimization by compositional modification founded on that structural scaffold.We contrast our focused hypothesis-driven approach with the recent screening studies that cover a much broader range of chemistries and do not target novel structural motifs. These approaches are good at interpolation and identifying the low hanging fruit for substitutional chemistry, but they struggle to deliver new chemistry knowledge, new understanding and new experimentally observed crystal structures. We comment on reporting the large number of proposed hypothetical structures when considering advances in prediction and the importance of context of the size of the chemical space including continuous composition variation and disorder. An example is the difference between predicting superstructures of known parent structures and experimentally realiz","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":"58 9","pages":"1355-1365"},"PeriodicalIF":16.4,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12060266/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143950772","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}

{"title":"Elucidating the Structure of Melanin and Its Structure-Property Correlation.","authors":"Arpan Choudhury, Debashree Ghosh","doi":"10.1021/acs.accounts.5c00120","DOIUrl":"https://doi.org/10.1021/acs.accounts.5c00120","url":null,"abstract":"&lt;p&gt;&lt;p&gt;ConspectusMelanin, specifically eumelanin, is a brownish-black pigment abundant in nature. It is a heterogeneous biopolymer known most commonly for its spectacular photoprotection property in humans, animals, and plants. Numerous other properties of eumelanin have recently been identified, including radical scavenging, thermal regulation, charge transport, etc. While the presence and significance of melanin have long been accepted, its exact chemical makeup remains unclear. Melanin has an inherent diversity of structure and complexity, making understanding many of its properties challenging. Therefore, there are large gaps in our understanding of the structure-property relationship in melanin. On the other hand, due to its diverse properties and biocompatibility, there is significant interest in engineering such biomimetic devices and materials with targeted properties utilizing melanin-like scaffolds. Furthermore, recent efforts toward understanding the molecular origin of its properties are also based on synthetic melanin analogs. For all these reasons, understanding the structure of melanin and its structure-property relationship remains pivotal to much of the progress in this direction.Our research has revolved around providing new insights into the structure of melanin and its structure-function correlations for properties such as absorption spectra, electron transport, and photoprotection. We have used tools based on a combination of computational chemistry and machine learning to answer these questions. Many of these methods and protocols developed in the group for solving this problem can be utilized for other problems of similar complexity.The difficulties in elucidating these aspects of melanin chemistry lie in its inherent structural and chemical diversity. It is a biopolymer with heterogeneity in monomeric units, oxidation states, polymerization site, and significant conformational degrees of freedom. Many of the attractive properties of melanin are a direct consequence of this diversity. One such property is its broadband absorption spectra, which allow it to absorb light across the UV-visible range and, therefore, function as a photoprotective agent against solar radiation. The melanin absorption spectra are unusual in their monotonic and featureless form. It is now well-accepted that both structural and chemical heterogeneity are responsible for these unusual spectra. Therefore, the problem of isolating specific chromophores responsible for different parts of the spectra becomes a daunting task. While previous computational and experimental studies have shown that diversity is central to this property, i.e., the spectrum is an ensemble or average spectrum, they have not been able to identify specific structures that are responsible. Therefore, we have used machine learning and artificial intelligence concepts to identify patterns and reconstruct particular structures. We have shown, with the help of machine learning and compu","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":"58 9","pages":"1509-1518"},"PeriodicalIF":16.4,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143950849","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":"Synthesis through C(sp³)-C(sp²) Bond Scission in Alkenes and Ketones.","authors":"Michal Šimek, Jeremy H Dworkin, Ohyun Kwon","doi":"10.1021/acs.accounts.5c00156","DOIUrl":"10.1021/acs.accounts.5c00156","url":null,"abstract":"&lt;p&gt;&lt;p&gt;ConspectusThe homolytic cleavage of C-C bonds adjacent to functional groups has recently become a popular strategy for restructuring the skeletons of complex organic molecules. In contrast to the traditional reactivity profiles of polar bond disconnections, homolytic scission furnishes carbon-centered free radicals primed for controlled termination with a diverse range of radicophiles. Beyond standard radical capture, transition-metal catalysis facilitates sophisticated C-C and C-heteroatom bond-forming reactions. Intensive efforts have been focused over many years into the cleavage of the neighboring C-C bonds of carboxylic acids and alcohols. Despite the ubiquity of alkenes and ketones in natural products, feedstock chemicals, and common synthetic intermediates, much less attention has been paid to exploiting their potential in diversifying chiral pool materials, such as terpenes and terpenoids. Defunctionalization in this manner is a powerful approach for synthesizing high-value chemicals and advanced synthetic intermediates because of the possibility to reconstruct and further decorate chirality-bearing carbon skeletons. Motivated by synthetic necessity, since 2018 our group has focused on developing ozonolysis-based dealkenylative molecular diversification, and we expanded into deacylation in 2025. In this Account, we chronicle our initial motivation, describe the historical background, and summarize our research into dealkenylative and deacylative synthesis. Our dealkenylative approach capitalizes on the ozonolysis of alkenes in MeOH to generate α-methoxyhydroperoxides primed for a reaction with reducing agents. Their reduction through single electron transfer, mediated by a transition metal, leads to the formation of an alkoxyl radical that undergoes rapid β-scission, furnishing both a carbon-centered free radical and an ester group derived from the acetal carbon atom. The produced free radical can be strategically terminated by radicophiles, thereby delivering remodeled chiral molecules. Using this concept, we have developed hydrodealkenylation (through hydrogen atom transfer from benzenethiol), dealkenylative thiylation (through thiyl group transfer from diaryl disulfides), alkenylation (through addition/elimination with nitrostyrenes), and oxodealkenylation (through treatment with TEMPO followed by oxidation). Furthermore, kinetic analysis has enabled the development of a catalytic Fe&lt;sup&gt;II&lt;/sup&gt;/vitamin C system for dealkenylative alkynylation and halodealkenylation. Synergizing ozonolysis and copper catalysis has recently enabled aminodealkenylation through net-redox-neutral C-C cleavage followed by C-N bond formation. Although the high oxidation potential of ozone relative to organic compounds makes alkene-to-peroxide conversion possible, it also limits the applicability of dealkenylative techniques for substrates featuring ozone-sensitive functional groups. We recently overcame this constraint by first applying Isayama-Mukayi","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":"58 9","pages":"1547-1561"},"PeriodicalIF":16.4,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12075848/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143950646","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}