Amogh Kinikar, Xiao-Ye Wang, Marco Di Giovannantonio, José I. Urgel, Pengcai Liu, Kristjan Eimre, Carlo A. Pignedoli*, Samuel Stolz, Max Bommert, Shantanu Mishra, Qiang Sun, Roland Widmer, Zijie Qiu, Akimitsu Narita, Klaus Müllen*, Pascal Ruffieux and Roman Fasel*,
{"title":"纳米石墨烯表面合成中的立体选择性 [3 + 3] 环芳香化反应","authors":"Amogh Kinikar, Xiao-Ye Wang, Marco Di Giovannantonio, José I. Urgel, Pengcai Liu, Kristjan Eimre, Carlo A. Pignedoli*, Samuel Stolz, Max Bommert, Shantanu Mishra, Qiang Sun, Roland Widmer, Zijie Qiu, Akimitsu Narita, Klaus Müllen*, Pascal Ruffieux and Roman Fasel*, ","doi":"10.1021/acsnanoscienceau.3c00062","DOIUrl":null,"url":null,"abstract":"<p >Surface-catalyzed reactions have been used to synthesize carbon nanomaterials with atomically predefined structures. The recent discovery of a gold surface-catalyzed [3 + 3] cycloaromatization of isopropyl substituted arenes has enabled the on-surface synthesis of arylene-phenylene copolymers, where the surface activates the isopropyl substituents to form phenylene rings by intermolecular coupling. However, the resulting polymers suffered from undesired cross-linking when more than two molecules reacted at a single site. Here we show that such cross-links can be prevented through steric protection by attaching the isopropyl groups to larger arene cores. Upon thermal activation of isopropyl-substituted 8,9-dioxa-8a-borabenzo[<i>fg</i>]tetracene on Au(111), cycloaromatization is observed to occur exclusively between the two molecules. The cycloaromatization intermediate formed by the covalent linking of two molecules is prevented from reacting with further molecules by the wide benzotetracene core, resulting in highly selective one-to-one coupling. Our findings extend the versatility of the [3 + 3] cycloaromatization of isopropyl substituents and point toward steric protection as a powerful concept for suppressing competing reaction pathways in on-surface synthesis.</p>","PeriodicalId":29799,"journal":{"name":"ACS Nanoscience Au","volume":null,"pages":null},"PeriodicalIF":4.8000,"publicationDate":"2023-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsnanoscienceau.3c00062","citationCount":"0","resultStr":"{\"title\":\"Sterically Selective [3 + 3] Cycloaromatization in the On-Surface Synthesis of Nanographenes\",\"authors\":\"Amogh Kinikar, Xiao-Ye Wang, Marco Di Giovannantonio, José I. Urgel, Pengcai Liu, Kristjan Eimre, Carlo A. Pignedoli*, Samuel Stolz, Max Bommert, Shantanu Mishra, Qiang Sun, Roland Widmer, Zijie Qiu, Akimitsu Narita, Klaus Müllen*, Pascal Ruffieux and Roman Fasel*, \",\"doi\":\"10.1021/acsnanoscienceau.3c00062\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p >Surface-catalyzed reactions have been used to synthesize carbon nanomaterials with atomically predefined structures. The recent discovery of a gold surface-catalyzed [3 + 3] cycloaromatization of isopropyl substituted arenes has enabled the on-surface synthesis of arylene-phenylene copolymers, where the surface activates the isopropyl substituents to form phenylene rings by intermolecular coupling. However, the resulting polymers suffered from undesired cross-linking when more than two molecules reacted at a single site. Here we show that such cross-links can be prevented through steric protection by attaching the isopropyl groups to larger arene cores. Upon thermal activation of isopropyl-substituted 8,9-dioxa-8a-borabenzo[<i>fg</i>]tetracene on Au(111), cycloaromatization is observed to occur exclusively between the two molecules. The cycloaromatization intermediate formed by the covalent linking of two molecules is prevented from reacting with further molecules by the wide benzotetracene core, resulting in highly selective one-to-one coupling. Our findings extend the versatility of the [3 + 3] cycloaromatization of isopropyl substituents and point toward steric protection as a powerful concept for suppressing competing reaction pathways in on-surface synthesis.</p>\",\"PeriodicalId\":29799,\"journal\":{\"name\":\"ACS Nanoscience Au\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":4.8000,\"publicationDate\":\"2023-12-22\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://pubs.acs.org/doi/epdf/10.1021/acsnanoscienceau.3c00062\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"ACS Nanoscience Au\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://pubs.acs.org/doi/10.1021/acsnanoscienceau.3c00062\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"NANOSCIENCE & NANOTECHNOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACS Nanoscience Au","FirstCategoryId":"1085","ListUrlMain":"https://pubs.acs.org/doi/10.1021/acsnanoscienceau.3c00062","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"NANOSCIENCE & NANOTECHNOLOGY","Score":null,"Total":0}
Sterically Selective [3 + 3] Cycloaromatization in the On-Surface Synthesis of Nanographenes
Surface-catalyzed reactions have been used to synthesize carbon nanomaterials with atomically predefined structures. The recent discovery of a gold surface-catalyzed [3 + 3] cycloaromatization of isopropyl substituted arenes has enabled the on-surface synthesis of arylene-phenylene copolymers, where the surface activates the isopropyl substituents to form phenylene rings by intermolecular coupling. However, the resulting polymers suffered from undesired cross-linking when more than two molecules reacted at a single site. Here we show that such cross-links can be prevented through steric protection by attaching the isopropyl groups to larger arene cores. Upon thermal activation of isopropyl-substituted 8,9-dioxa-8a-borabenzo[fg]tetracene on Au(111), cycloaromatization is observed to occur exclusively between the two molecules. The cycloaromatization intermediate formed by the covalent linking of two molecules is prevented from reacting with further molecules by the wide benzotetracene core, resulting in highly selective one-to-one coupling. Our findings extend the versatility of the [3 + 3] cycloaromatization of isopropyl substituents and point toward steric protection as a powerful concept for suppressing competing reaction pathways in on-surface synthesis.
期刊介绍:
ACS Nanoscience Au is an open access journal that publishes original fundamental and applied research on nanoscience and nanotechnology research at the interfaces of chemistry biology medicine materials science physics and engineering.The journal publishes short letters comprehensive articles reviews and perspectives on all aspects of nanoscience and nanotechnology:synthesis assembly characterization theory modeling and simulation of nanostructures nanomaterials and nanoscale devicesdesign fabrication and applications of organic inorganic polymer hybrid and biological nanostructuresexperimental and theoretical studies of nanoscale chemical physical and biological phenomenamethods and tools for nanoscience and nanotechnologyself- and directed-assemblyzero- one- and two-dimensional materialsnanostructures and nano-engineered devices with advanced performancenanobiotechnologynanomedicine and nanotoxicologyACS Nanoscience Au also publishes original experimental and theoretical research of an applied nature that integrates knowledge in the areas of materials engineering physics bioscience and chemistry into important applications of nanomaterials.