{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/127423"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/127423","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"The tension activated C–C bond: physical organic models and functional organic materials","abstract":"Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2026-12-01","abstract_html":"Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2026-12-01","abstract_has_math":false,"creators":["Sun, Yunyan"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Chemistry","degree_department":null,"school":null,"contributors":["Moore, Jeffrey Scott","Chan, Jefferson","Suslick, Kenneth","Guironnet, Damien"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2024,"date_issued":"2024-08-06","date_published":"2024-08-06","updated_at":"2026-07-22T22:25:04Z","subjects":["Mechanochemistry","Mechanophore","Carbon–carbon Bond Activation","Reactivity"],"languages":["en","eng"],"rights":["© 2024 by Yunyan Sun. All rights reserved."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/2142/127423","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Moore, Jeffrey Scott","Chan, Jefferson","Suslick, Kenneth","Guironnet, Damien"]},{"key":"dc:creator","label":"Author","values":["Sun, Yunyan"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2024-08-06","2024-12"]},{"key":"dc:type","label":"Dc Type","values":["text","Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Chemistry"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Mechanochemistry","Mechanophore","Carbon–carbon Bond Activation","Reactivity"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en","eng"]},{"key":"dc:rights","label":"Dc Rights","values":["© 2024 by Yunyan Sun. All rights reserved."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://hdl.handle.net/2142/127423"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2026-12-01","The student, Yunyan Sun, accepted the attached license on 2024-07-23 at 09:24.","The student, Yunyan Sun, submitted this Dissertation for approval on 2024-07-23 at 09:37.","This Dissertation was approved for publication on 2024-08-06 at 09:07.","DSpace SAF Submission Ingestion Package generated from Vireo submission #21160 on 2025-03-28 at 14:52:49","Carbon–carbon (C–C) bond is widely acknowledged for its strength, yet its scission is surprisingly common in a diverse array of selective mechanochemical transformations under tension. Polymer mechanochemistry employs polymer chains to direct and transduce tensile force, setting an ideal stage for investigating the tension activated C–C bond in both mechanochemical reactions and mechano-responsive materials. Whereas C–C bond scission under tensile force has been known since middle 20th century, the scope of reactions initiated from tensioned C–C bond remains limited, involving mostly retro-pericyclic reactions. In addition, the vectorial nature of force results in intricate coupling with reaction trajectories, making it challenging to understand and predict structure-reactivity relationships under tension using conventional chemical intuitions. To tackle these two challenges, this thesis will be focusing on developing new mechanochemical reactions using tension activated C–C bond and applying them in mechano-responsive materials, as well as developing a physical organic model to build an intuitive picture of reactivity under tension. In the second chapter of this thesis, I detail the development of an unprecedented mechanochemical mechanism based on the tension activated C–C bond, named diradical elimination cascade. This strategy enables the design and synthesis of a bifunctional mechanosensitive motif (i.e., mechanophore) built from norborn-2-en-7-one (NEO) that not only releases carbon monoxide (CO) as a gaseous signaling molecule (GSM), but also turns on the aggregation-induced emission upon mechanochemical activation. The third chapter explores the further generalization of the diradical elimination cascade strategy to release sulfur dioxide (SO2) as another GSM with therapeutic potential. A thermally stable but mechanochemically labile mechanophore was designed based on an 8-thiabicyclo[3.2.1]octane 8,8-dioxide (TBO) motif. We quantified the mechanochemical reactivity of TBO by single molecule force spectroscopy and resolved its single-event activation. The mechanism of TBO activation was also investigated using ab initio steered molecular dynamic simulations. The fourth chapter discusses the development of an intuitive physical organic model to understand and predict the reactivity of C–C bond under tensile force, by leveraging two key molecular features: the effective force constant (keff) and reaction energy (ΔE). Through a comprehensive experimental and computational investigation with four norborn-2-en-7-one (NEO) mechanophores, we establish the relationship between these features and the force-dependent energetic changes along the reaction pathways. A multivariate linear model was then established to predict the transition force (f*) of more than 30 C–C bonds in various mechanophores. In the fifth chapter, a new NEO mechanophore scaffold was designed and synthesized to achieve mechano-activatable multi-color photoluminescence and white emission in aggregated states. The new NEO derivates were examined in both solution ultrasonication and solid-state grinding. Energy transfer between nascent and activated states was observed in NEOs bearing strong electron-donating groups. The energy transfer process was further regulated by tuning mechanophore activation and incorporation, enabling the development of force-controlled multicolor fluorescence and white emission. Finally, chapter six will outline future opportunities for the tension-activated C–C bond and the diradical elimination cascade strategy."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["The tension activated C–C bond: physical organic models and functional organic materials"]}]}],"canonical_facts":{"dc:contributor":["Moore, Jeffrey Scott","Chan, Jefferson","Suslick, Kenneth","Guironnet, Damien"],"dc:creator":["Sun, Yunyan"],"dc:date":["2024-08-06","2024-12"],"dc:description":["Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2026-12-01","The student, Yunyan Sun, accepted the attached license on 2024-07-23 at 09:24.","The student, Yunyan Sun, submitted this Dissertation for approval on 2024-07-23 at 09:37.","This Dissertation was approved for publication on 2024-08-06 at 09:07.","DSpace SAF Submission Ingestion Package generated from Vireo submission #21160 on 2025-03-28 at 14:52:49","Carbon–carbon (C–C) bond is widely acknowledged for its strength, yet its scission is surprisingly common in a diverse array of selective mechanochemical transformations under tension. Polymer mechanochemistry employs polymer chains to direct and transduce tensile force, setting an ideal stage for investigating the tension activated C–C bond in both mechanochemical reactions and mechano-responsive materials. Whereas C–C bond scission under tensile force has been known since middle 20th century, the scope of reactions initiated from tensioned C–C bond remains limited, involving mostly retro-pericyclic reactions. In addition, the vectorial nature of force results in intricate coupling with reaction trajectories, making it challenging to understand and predict structure-reactivity relationships under tension using conventional chemical intuitions. To tackle these two challenges, this thesis will be focusing on developing new mechanochemical reactions using tension activated C–C bond and applying them in mechano-responsive materials, as well as developing a physical organic model to build an intuitive picture of reactivity under tension. In the second chapter of this thesis, I detail the development of an unprecedented mechanochemical mechanism based on the tension activated C–C bond, named diradical elimination cascade. This strategy enables the design and synthesis of a bifunctional mechanosensitive motif (i.e., mechanophore) built from norborn-2-en-7-one (NEO) that not only releases carbon monoxide (CO) as a gaseous signaling molecule (GSM), but also turns on the aggregation-induced emission upon mechanochemical activation. The third chapter explores the further generalization of the diradical elimination cascade strategy to release sulfur dioxide (SO2) as another GSM with therapeutic potential. A thermally stable but mechanochemically labile mechanophore was designed based on an 8-thiabicyclo[3.2.1]octane 8,8-dioxide (TBO) motif. We quantified the mechanochemical reactivity of TBO by single molecule force spectroscopy and resolved its single-event activation. The mechanism of TBO activation was also investigated using ab initio steered molecular dynamic simulations. The fourth chapter discusses the development of an intuitive physical organic model to understand and predict the reactivity of C–C bond under tensile force, by leveraging two key molecular features: the effective force constant (keff) and reaction energy (ΔE). Through a comprehensive experimental and computational investigation with four norborn-2-en-7-one (NEO) mechanophores, we establish the relationship between these features and the force-dependent energetic changes along the reaction pathways. A multivariate linear model was then established to predict the transition force (f*) of more than 30 C–C bonds in various mechanophores. In the fifth chapter, a new NEO mechanophore scaffold was designed and synthesized to achieve mechano-activatable multi-color photoluminescence and white emission in aggregated states. The new NEO derivates were examined in both solution ultrasonication and solid-state grinding. Energy transfer between nascent and activated states was observed in NEOs bearing strong electron-donating groups. The energy transfer process was further regulated by tuning mechanophore activation and incorporation, enabling the development of force-controlled multicolor fluorescence and white emission. Finally, chapter six will outline future opportunities for the tension-activated C–C bond and the diradical elimination cascade strategy."],"dc:format":["application/pdf"],"dc:identifier":["https://hdl.handle.net/2142/127423"],"dc:language":["en","eng"],"dc:rights":["© 2024 by Yunyan Sun. All rights reserved."],"dc:subject":["Mechanochemistry","Mechanophore","Carbon–carbon Bond Activation","Reactivity"],"dc:title":["The tension activated C–C bond: physical organic models and functional organic materials"],"dc:type":["text","Thesis"],"thesis:degree_discipline":["Chemistry"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:04Z"}