679 research outputs found
Ruthenium‐Catalyzed Remote‐Difunctionalization of Nonactivated Alkenes for Double meta‐C(sp2)−H/C‐6(sp3)−H Functionalization
No full textTwofold distal C−H functionalization was accomplished by difunctionalization of nonactivated alkenes to provide rapid access to multifunctionalized molecules. The multicomponent ruthenium-catalyzed remote 1,n-difunctionalization (n=6,7) of nonactivated alkenes with fluoroalkyl halides and heteroarenes in a modular manner is reported. The meta-C(sp2)−H/C-6(sp3)−H distal functionalization featured mild conditions, unique selectivity, and broad substrate scope with a domino process for twofold remote C(sp2)−H/C(sp3)−H activation of the sequential formation of three different carbon-centered radicals. A plausible mechanism was proposed based on detailed experimental and computational studies.European Research Council http://dx.doi.org/10.13039/501100000781DFG http://dx.doi.org/10.13039/501100001659Alexander von Humboldt-Stiftung http://dx.doi.org/10.13039/100005156China Sponsorship Council http://dx.doi.org/10.13039/50110000454
Electrochemical Rearrangement for Remote Functionalizations of Unactivated Alkenes
No full textAn electrochemical strategy for the dual functionalizations of unactivated alkenes through an intramolecular migration process was realized in the absence of sacrificial chemical oxidants and noble-metal catalysts under mild reaction conditions. The electrochemistry enabled a (hetero)aryl migration while providing access to alkenyl/alkynyl-migration products. Thus, electricity was employed for the formation of functionalized fluoroalkyl radicals through activation of C−H/C−Br bonds from fluorinated esters. Thereby, we obtained a variety of di and mono-fluorinated alkyl products with good functional group tolerance as well as chemo, and regioselectivities. Likewise, defluorinative allylation of α-carbonyl alkyl bromides proved viable. The reaction mechanism was established by experiments and computations.European Research Council http://dx.doi.org/10.13039/501100000781Alexander von Humboldt-Stiftung http://dx.doi.org/10.13039/100005156China Scholarship Council http://dx.doi.org/10.13039/501100004543Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/50110000165
Electrochemical C7‐Indole Alkenylation via Rhodium Catalysis
No full textAbstract Indole derivatives are fundamental structural units in many bioactive compounds and molecular materials. The site‐selective C7‐functionalization of these moieties has been proven to be extremely challenging due to the inherent reactivity of the C2‐ and C3‐positions. Herein, we report the first electro‐C7‐alkenylation of indoles. This novel and sustainable methodology provides highly exclusive access to the C7‐position devoid of often toxic and expensive chemical oxidants. Moreover, an array of substrates was successfully alkenylated at the C7‐position, and versatile product diversification was achieved.Deutsche Forschungsgemeinschaft https://doi.org/10.13039/50110000165
‐Koordination ermöglicht durch die Wasserstoffbildungsreaktion (HER)
No full textFundacja na rzecz Nauki Polskiej https://doi.org/10.13039/501100001870European Research Council https://doi.org/10.13039/501100000781Narodowa Agencja Wymiany Akademickiej https://doi.org/10.13039/501100014434China Scholarship Council https://doi.org/10.13039/50110000454
Understanding and Describing London Dispersion Effects in Transition-Metal-Catalyzed C–H Activations
No full textAbstract Transition-metal-catalyzed C–H activation has emerged as a powerful strategy for molecular synthesis with unique levels of resource economy. Weak secondary dispersion interactions were found to play an essential role in these transformations in terms of kinetic efficacy and selectivity. This Account summarizes our group’s recent progress in the rationalization and quantification of London dispersion effects within the transition-metal-catalyzed C–H activation. 1 Introduction 2 Annulation Reactions 3 Alkylation Reactions 4 Arylation Reactions 5 Olefination Reactions 6 Oxygenation Reactions 7 Conclusio
)−H‐Funktionalisierung
No full textAbstract Die zweifache distale C−H‐Funktionalisierung wurde durch Difunktionalisierung von nicht aktivierten Alkenen erreicht, um einen schnellen Zugang zu hochfunktionalisierten Molekülen zu ermöglichen. Wir berichten hier über die Mehrkomponten‐Ruthenium‐katalysierte 1,n‐Ferndifunktionalisierung ( n =6,7) von nicht aktivierten Alkenen mit Fluoralkylhalogeniden und Heteroarenen in modularer Weise. Die distale meta ‐C(sp 2 )−H/C‐6(sp 3 )−H‐Funktionalisierung zeichnete sich durch milde Bedingungen, einzigartige Selektivität und einen breiten Substratbereich mit einem Domino‐Prozess für die zweifache C(sp 2 )−H/C(sp 3 )−H‐Fernaktivierung der sequentiellen Bildung von drei verschiedenen kohlenstoff‐zentrierten Radikalen aus. Auf der Grundlage detaillierter experimenteller und rechnerischer Studien wurde ein plausibler Mechanismus vorgeschlagen.European Research Council https://doi.org/10.13039/501100000781Deutsche Forschungsgemeinschaft https://doi.org/10.13039/501100001659Alexander von Humboldt-Stiftung https://doi.org/10.13039/100005156China Scholarship Council https://doi.org/10.13039/50110000454
Late-Stage C–H Diversifications with Ambiphilic α-Bromoboronates: Versatile Access to Transformable meta -Boroalkyl Scaffolds
No full textRuthenium‐Catalyzed Aminocarbonylation with Isocyanates Through Weak Coordinating Groups
No full textAbstract Introducing amide functional groups under mild conditions has growing importance owing to the prevalence of such moiety in biologically active molecules. Herein, we disclose a mild protocol for the directed ruthenium‐catalyzed C−H aminocarbonylation with isocyanates as the amidating agents developed through high‐throughput experimentation (HTE). The redox‐neutral and base‐free reaction is guided by weakly Lewis basic functional groups, including anilides, lactams and carbamates to access anthranilamide derivatives. The synthetic utility of this transformation is reflected by large‐scale synthesis and late‐stage functionalization.Horizon 2020 Framework Programme https://doi.org/10.13039/100010661China Scholarship Council https://doi.org/10.13039/50110000454
Ruthenaphoto-catalyzed ortho-C−H alkylation with secondary alkyl halides: SET-enabled ruthenium(II/III/IV) manifold
No full texthttp://dx.doi.org/10.13039/100019180 HORIZON EUROPE European Research Councilhttp://dx.doi.org/10.13039/501100001659 German Research Foundationhttp://dx.doi.org/10.13039/501100004543 China Scholarship Councilhttp://dx.doi.org/10.13039/501100000781 European Research Councilhttp://dx.doi.org/10.13039/100005156 Alexander von Humboldt-Stiftun
- …
