{"675361":{"#nid":"675361","#data":{"type":"event","title":"Colloquium Seminar - Prof. Jake Soper (Georgia Institute of Technology)","body":[{"value":"\u003Cp\u003E\u003Ca\u003ECobalt Photoredox Catalysts for Selective Radical Trifluoromethylations\u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EAbstract:\u0026nbsp;\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EDirect trifluoromethylation of unactivated C\u2013H bonds offers a powerful, atom-economical route to CF3-containing molecules of interest in pharma and agrochemicals. Photoredox methods to generate electrophilic \u2022CF3 are robust and powerful, but outer-sphere methods suffer from the lack of selectivity inherent to \u2022CF3 radicals. Organometallic approaches tantalize, but metal-catalyzed trifluoromethylations are frequently challenged by the intrinsic properties of the M\u2212CF3 intermediates. Whereas early transition metal M\u2212CF3 bonds readily undergo \u003Cem\u003E\u03b1\u003C\/em\u003E-fluoride abstraction to generate difluoromethyl carbene complexes, M\u2212CF3 bonds to low-valent later 3d metals are often thermodynamically robust and kinetically inert. We have developed a photoinduced method to activate thermodynamically stable CoIII\u2013CF3 bonds for selective arene C\u2013H trifluoromethylations. Central to this strategy is the capacity of pincer (OCO)Co complexes to function as combined chromophores and organometallic reaction centers. Low energy visible light capture leads to intramolecular LMCT from a redox-active [OCO] pincer ligand to Co, which destabilizes the Co\u2013CF3 bond toward homolysis and release of a persistent \u2022CF3 radical. The capacity of the Co(II) byproduct to catalyze H2 production permits direct arene C\u2013H trifluoromethylation without a sacrificial or substrate-derived oxidant. This seminar will describe our recent extensions to photocatalysis and ongoing efforts to elaborate regiospecific radical substitution via intramolecular photolytic arene C\u2013H trifluoromethylations and alkylations. Structure-property relationships will be presented, which are guiding new catalyst designs and establishing design principles for next generation base metal photocatalysis.\u003C\/p\u003E","summary":"","format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003EOne in the series of SoCB seminars.\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"School of Chemistry \u0026 Biochemistry -Seminar Series"}],"uid":"36441","created_gmt":"2024-07-05 18:07:05","changed_gmt":"2024-07-05 18:10:19","author":"slawrence67","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2024-08-22T15:30:00-04:00","event_time_end":"2024-08-22T16:30:00-04:00","event_time_end_last":"2024-08-22T16:30:00-04:00","gmt_time_start":"2024-08-22 19:30:00","gmt_time_end":"2024-08-22 20:30:00","gmt_time_end_last":"2024-08-22 20:30:00","rrule":null,"timezone":"America\/New_York"},"location":"MoSE - G011","extras":[],"groups":[{"id":"85951","name":"School of Chemistry and Biochemistry"}],"categories":[],"keywords":[],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1795","name":"Seminar\/Lecture\/Colloquium"}],"invited_audience":[{"id":"78761","name":"Faculty\/Staff"},{"id":"174045","name":"Graduate students"},{"id":"177814","name":"Postdoc"},{"id":"78751","name":"Undergraduate students"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003E\u003Cstrong\u003EHost:\u003C\/strong\u003E Prof. Jake D. Soper\u003C\/p\u003E","format":"limited_html"}],"email":[],"slides":[],"orientation":[],"userdata":""}}}