Site-Selective C–H Activation for Small Molecules and π-Conjugated Polymers

by Takuya Michiyuki
Doctoral thesis
Date of Examination:2025-11-11
Date of issue:2025-11-19
Advisor:Prof. Dr. Lutz Ackermann
Referee:Prof. Dr. Lutz Ackermann
Referee:Prof. Dr. Konrad Koszinowski
Referee:Prof. Dr. Dr. h.c. Lutz Tietze
Referee:Dr. Daniel Janßen-Müller
Referee:Prof. Dr. Nadja A. Simeth
Referee:Prof. Dr. Johannes C. L. Walker
Persistent Address: http://dx.doi.org/10.53846/goediss-11638

 

 

Files in this item

Name:Dissertation_Takuya_Michiyuki.pdf
Size:12.5Mb
Format:PDF

The following license files are associated with this item:

Abstract

English

The selective installation of organic fragments onto aromatic scaffolds remains a central challenge in organic synthesis. Due to growing concerns over resource depletion and environmental impact, chemists are increasingly striving not only to perform these reactions efficiently but also to render them more sustainable. In this regard, this thesis explores sustainable strategies that integrate cross-electrophile coupling and C–H activation through electrochemical or photochemical methodologies. First, a nickel-catalyzed electrochemical cross-electrophile coupling is presented. The reaction enables site-selective modification of non-prefunctionalized arenes through the formation of aryl sulfonium salts. Notably, one-pot electrocatalytic alkylations are viable, highlighting the user-friendly nature of the approach. Second, a low-temperature ruthenium-catalyzed C–H activation using ruthenium trichloride as a simple precatalyst is explored. The present ruthenium catalysis allows for ortho- or meta-functionalizations of diverse substrates, including pharmaceutical molecules and natural products. Electrochemical analysis supports a ruthenium(III/II) system through cathodic reduction. Third, a ruthenium-catalyzed C–H arylation polymerization proceeding at ambient temperature is showcased. The mild conditions are enabled by visible-light irradiation, affording polymers with narrow polydispersity and high chemoselectivity. Overall, these studies demonstrate how electrochemical and photochemical techniques can drive site-selective functionalizations in a sustainable manner, advancing the field of green organic synthesis.
Keywords: C–H Activation; Electrochemistry; Photochemistry; Cross-Electrophile Coupling; Polymers; Alkylation; Sulfonium Salts; Nickel; Arylation; Ruthenium; Polymerization; Organic Synthesis
 
Statistik